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NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
A crane is a type of tower that is equipped
with pulleys and cables and is used to lower and lift materials. Cranes are
most commonly used in industry that requires heavy machinery, such as construction
or other earth moving tasks.
There are many different styles and variation
of cranes that abound in the world. They are each used for specific
tasks and the majorities are used for industrial purposes and are considered
heavy equipment machinery.
Telescopic Crane
This crane has boom that consists of number of different fitted
tubes that reside inside each other. A hydraulic mechanism is what extends
or retracts the tubes to increase or decrease the length of the main boom.
  
  
Tower Crane
This crane is fixed to the ground and gives a great combination
of height and lifting capacity. It’s commonly used in construction to
build sky scrapers and other tall buildings.
To save space and to provide stability the vertical part
of the crane is typically braced directly onto the completed building which
is normally the concrete lift shaft located in the center.
 
  
Truck Mounted Crane
a crane that is mounted on a rubber tire truck that drives around
for maximum portability.
When
in operation Outriggers extend horizontally and then vertically to both level
and stabilize the crane for hoisting operations.
  
 
Rough terrain crane
this is a crane that is mounted on an undercarriage contains four
rubber tires and is designed for pick-up and carry operations.
Outriggers extend first horizontally and then vertically
to both level and stabilize the crane for hoisting operations.
  
  
Crawler crane
an undercarriage mounted crane that also has a set of tracks that
provide extra stability and mobility.
     
Loader crane
a loader crane is fitted to a trailer and used to unload/load goods
onto the trailer. It contains many different jointed sections that can
be folded into a smaller space when the crane is not being used. One
of the sections may be able to telescopic in and out.
  
  
Overhead crane or suspended crane
the hoist is located on a trolley that moves in one direction along
one or two beams and is always at a right angle. These cranes are often
mounted on the side of an assembly area.
  
  
Stacker crane
a crane with a mechanism similar to a forklift that is used in
automated warehouses. The crane moves on a track located in a warehouse
and the fork can be raised or lowered to various storage levels to retrieve
products.
Stacker cranes are most often used in hazardous environments
like freezer, so worker dos not have to tolerate harsh conditions.
  
 
A crane is a mechanical lifting device equipped
with hoists, wire ropes and sheaves that can be used both to lift and lower
materials and to move them horizontally. Cranes are commonly employed in the
construction industry and in manufacturing heavy equipment.
  
Cranes are machines that use levers and/or
pulleys to lift significant weights. A crane one passes on the road may look
like a fairly modern invention, but these machines have actually been used
for at least the past 2000 years, if not longer.
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
The Romans used cranes to build huge monuments.
Medieval churches were constructed with them. Also, the Egyptians may have
used them to create pyramids. The modern version can be either simple or complex,
and cranes vary based on their application.
A relatively simple crane is
the mobile crane. A telescopic boom (arm) or
steel truss mounts its movable platform. Either pulleys or levers raise the
boom. Generally a hook suspends from the boom.
The platform of a mobile crane can either have
traditional wheels, wheels designed for railroad tracks, or a caterpillar
track, which is useful for navigating unpaved and uneven surfaces.
Mobiles can be used for demolition or earthmoving
by replacing the hook with an appropriate tool, such as a wrecking ball or
bucket. Telescopic cranes, with a series of hydraulic tubes fit together to
form the boom, can also be mobile.
are both essentially mobile as well. The truck-mounted
crane generally has outriggers to increase its stability. Rough terrain cranes tend to have a base that resembles the
bottom of a 4-wheel drive vehicle.
Outriggers also stabilize these cranes. They
tend to be used in rough terrain, as the name suggests, and are frequently
used to pick up and transport materials.
have hydraulic powered booms fitted onto trailers.
They load goods onto the trailer and the jointed sections of the boom are
folded down when not in use.
The loader may also be considered telescopic,
as one section of the boom, in some designs, may telescope for ease of use.
are most frequently seen in automated warehouses
where they tend to follow an automatic retrieval system. For example, in huge
automated freezers, these cranes, equipped with forklift apparatus, can work
by remote, stacking or obtaining foods as needed. This retrieval system makes
it possible to keep workers out of the cold.
Most often found in ports and railroads, where
they unload and move huge containers off of ships and trains. The bases are huge crossbeams which run on rails, so lifted containers can be moved from one location to another.
The portainer is a special type of gantry that lifts materials on and off
ships.
mounted on barges or pontoons are also essential
to the shipping industry. Situated in water, they are used to construct ports,
salvage ships or build bridges.
Like portainers, floating cranes also can unload
ships. They are able to handle very heavy loads and awkwardly shaped containers.
conversely, do not generally have a moveable
base. These are often the tallest cranes, and have to be assembled piece by
piece. The base looks like a long ladder, and the boom is perpendicular to
the base.
Tower cranes are used to construct tall buildings,
and in the case of skyscrapers, the tower crane is often assembled and affixed
inside the building itself during construction.
represent a meeting of simple machines, used for
the purpose of reducing workload. However simple they may seem, they are instrumental
in many aspects of industry.
They can dig, move, create,
or destroy, depending on their type. Cranes
exemplify that sometimes the oldest ideas are the best ones.
An Increasingly Popular Alternative to Overhead Bridge Cranes
Long popular in Europe,
gantry cranes have become a widely accepted alternative to overhead bridge
cranes. This type of crane is similar to the bridge crane except that it runs
on a runway at the floor level. The bridge is supported by a pair of rigid
steel legs which are carried by a pair of end trucks along the floor level
runway.
- often costs
less than a bridge crane
- built to heavy
duty Class D specifications, which meet the demands of high duty cycles
and multiple shift operation, as well as providing decades of reliable service
for all applications
- available in
spans to 150 feet and capacities to 150 tons
- can be used
either indoors or outside
A combination of the bridge crane and gantry
crane. One leg rides on the floor, while the other side’s end truck rides
on a runway beam.
Unlike most gantry cranes, which run on ASCE rails
or an inverted angle iron, North American Industries offers gantry cranes
that are specially designed to allow
one leg to ride directly on a smooth concrete floor.
Thus, the cost and travel barriers normally associated
with gantry tracks are eliminated. For applications where a smooth, clean
floor is not possible, or in high capacities, our gantry cranes can ride on
a leveled, 1/2" high steel plate.
This floor-mounted plate provides an alternative
to a 4" high rail track and still permits unobstructed access to the
cranes’ work area by forklifts, work carts and personnel.
Because gantry cranes ride on
the ground rather than on overhead runways, they don't require a runway structure. Nor do they usually require concrete
foundations. Their installation is fast and simple.
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
Depending on the environment and application,
gantry cranes can sometimes provide the same material handling capabilities
as a comparable bridge crane system, but with a significant cost savings.
The following chart shows a typical example
of the cost savings in purchasing a gantry crane instead of an overhead bridge
crane.
Please note that this price workup is only
meant to be a demonstrative example of one instance where a gantry crane is
advantageous for the customer. Contact our sales department for more information
on whether a gantry crane is the best option for your specific needs.
For a 10 ton 60’ span Single Girder crane with
a 200’ Runway 25’ high:
| |
Bridge
Crane
|
Gantry
Crane
|
|
Crane
|
$29,280
|
$40,240
|
|
Runway
|
$29,108
|
N/A
|
|
Installation
|
$22,915
|
$19,100
|
|
Crane Rail
|
ASCE Rail:
$2,900
|
Track: $6,880
|
|
TOTAL:
|
$84,205
|
$66,220
|
|
Cost Difference:
|
$17,985
|
However,
not all Gantry
Cranes cost less than their bridge crane counterparts. A gantry
crane is a more cost-effective alternative if:
- You are currently
in a leased facility and do not want to make a major investment in a bridge
crane runway structure.
- You may be
planning to move the crane in the near future and want to take your entire
investment with you.
- You require
a crane system that moves loads between the interior and exterior of your
building.
- You need long
runway structures of over 150 feet where the runway steel and f
-
- Work Station Bridge Cranes
- Foundation
costs are very high.
Work Station Bridge
Cranes
Enclosed track workstation bridge cranes by
your supplier are offered in either stand alone workstation bridge crane kits,
also known as free standing workstation bridge cranes, or ceiling mounted
workstation bridge crane kits.
Features of Track Workstation
Bridge Cranes
Enclosed track workstation bridge
crane systems are pre-engineered modular and infinitely expandable, reduce
vertical space and support requirements, and
are ergonomically designed with a 100 to 1 productivity ratio and utilize
a self cleaning V-profile design which maintains alignment of end trucks and
trolleys.
Bridge cranes have large diameter polyamide
wheels, which are extremely free rolling (steel wheels optional), with steel
guide rollers to prevent end trucks from racking or binding.
Stand Alone Workstation
Bridge Crane
Components
Ceiling Mounted Workstation
Bridge Crane
Components
Easy, ergonomic movement
An operator pushing a 1000 lb. load will experience
a force of approximately 10 lb. to begin moving the load and 8 lb. to continue
moving the load (100 to 1 ratio).
Manual cranes also operate more
quickly than motorized cranes, making
a workstation bridge crane ideal for fast paced work environments.
Your supplier specializes in customized crane
design to meet any specific requirements. With a capable engineering department,
your supplier can customize any standard product or bridge crane or design
a system from the ground up.
From 2-D layouts to complete solid models,
your supplier can create a custom enclosed track workstation bridge crane
system design in a timely manner. Finite Element Analysis (FEA) is utilized
to assure that all custom designs meet the highest standards of safety. your
supplier prides itself on developing creative solutions to customer’s material
handling needs.
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
In addition to the usual customizations
for special heights, spans, and lengths on a bridge crane, your supplier can
specially design power drives for
many models of our enclosed track workstation bridge crane systems. Special
mounting needs can also be met with custom design.
Workstation bridge crane systems can be equipped
with lighter weight ALU-TRACK®
bridges. The possibilities are unlimited-your supplier can design to meet
your needs!
Nameplate bridge capacity represents the rated
load on the hoist hook. The load rating of a hoist shall not exceed the bridge
rating. your supplier’s design includes an allowance of 15% of nameplate capacity
for dead weight of the trolley and hoist. An additional allowance of 25% of
nameplate capacity is also included for impact.
Workstation bridge cranes are designed for “heavy
service” (with standard air hoists or electric hoists) as defined by the Monorail
Manufacturer’s Association (MMA) as
defined:
- System or equipment
is used where operational time is up to 100% of the work period and lifted
load is at 50% or below rated capacity.
- System or equipment
is used where operational time is less than 50% of work period and lifted
load is greater than 50% of rated capacity.
- Applications
involving vacuums, magnets, or other high impact lifters are considered
severe usage (continuous service) and require special design considerations.
Please contact factory for special design pricing.
- Consult factory
for usage other than moderate and all instances of high cycle rates or high
impact applications such as high-speed air or electric hoists, vacuum lifters,
or magnets. Factory MUST approve ALL such applications.
your supplier’s Workstation
Bridge cranes
are 100% packaged for the best possible paint finish protection during shipment.
All runways and bridges are separated and covered with a layer of micro foam.
Heavy-duty corner boards are applied and then each bundle is passed through
a stretch-wrapping machine. The bundles are then steel banded with wooden
skids nailed through the bands for easy forklift handling.
All your supplier’s enclosed track workstation
bridge crane components are packed securely in heavy-duty cardboard cartons
and skidded as needed.
Spray paint for touch-up is provided in appropriate
quantity, although it is seldom needed because of the high level of packaging
protection.
What are the Different Types of Cranes?
Cranes are machines that use levers and/or pulleys
to lift significant weights. A crane one passes on the road may look like
a fairly modern invention, but these machines have actually been used for
at least the past 2000 years, if not longer.
The Romans used cranes to build huge monuments.
Medieval churches were constructed with them. Also, the Egyptians may have
used them to create pyramids. The modern version can be either simple or complex,
and cranes vary based on their application.
A relatively simple crane is the mobile crane. A telescopic boom (arm) or
steel truss mounts its movable platform. Either pulleys or levers raise the
boom. Generally a hook suspends from the boom.
The platform of a mobile crane can either have traditional wheels,
wheels designed for railroad tracks, or a caterpillar track, which is useful
for navigating unpaved and uneven surfaces.
Mobiles can be used for demolition or earthmoving
by replacing the hook with an appropriate tool, such as a wrecking ball or
bucket. Telescopic cranes, with a series of hydraulic tubes fit together to
form the boom, can also be mobile.
Truck mounted and rough terrain cranes are both essentially mobile
as well. The truck-mounted crane generally has outriggers to increase its
stability.
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
Rough terrain cranes tend to have a base that
resembles the bottom of a 4-wheel drive vehicle. Outriggers also stabilize
these cranes. They tend to be used in rough terrain, as the name suggests,
and are frequently used to pick up and transport materials.
Loader cranes have hydraulic powered booms fitted onto trailers. They
load goods onto the trailer and the jointed sections of the boom are folded
down when not in use. The loader may also be considered telescopic, as one
section of the boom, in some designs, may telescope for ease of use.
Stacker cranes are most frequently seen in automated
warehouses where they tend to follow an automatic retrieval system. For example, in huge automated freezers, these
cranes, equipped with forklift apparatus, can work by remote, stacking or
obtaining foods as needed. This retrieval system makes it possible to keep
workers out of the cold.
Gantry cranes are most often found in ports and railroads, where
they unload and move huge containers off of ships and trains. The bases are
huge crossbeams which run on rails, so lifted containers can be moved from
one location to another. The portainer is a special type of gantry that lifts
materials on and off ships.
Floating cranes mounted on barges or pontoons are also essential to the shipping
industry. Situated in water, they are used to construct ports, salvage ships
or build bridges. Like portainers, floating cranes also can unload ships.
They are able to handle very heavy loads and awkwardly shaped containers.
Tower cranes, conversely, do not generally have a moveable base. These are
often the tallest cranes, and have to be assembled piece by piece.
The base looks like a long ladder, and the boom
is perpendicular to the base. Tower cranes are used to construct tall buildings,
and in the case of skyscrapers, the tower crane is often assembled and affixed
inside the building itself during construction.
All cranes represent a meeting of simple machines,
used for the purpose of reducing workload. However simple
they may seem, they are instrumental in many aspects of industry. They can
dig, move, create, or destroy, depending on their type. Cranes exemplify that
sometimes the oldest ideas are the best ones.
A crane is a mechanical lifting device equipped
with hoists, wire ropes and sheaves that can be used both to lift and lower
materials and to move them horizontally. Cranes are commonly employed in the
construction industry and in manufacturing heavy equipment.
Managing Mobile Crane
Hazards - Crane Selection, Site Review & Setup
- Considerations
for proper crane selection and the various types of mobile cranes used in
construction.
- Factors that
affect stability, capacity and the proper set-up of mobile cranes.
Crane Selection
Considerations:
- The weights,
dimensions and lift radii expected.
- The type of
lifting to be done.
- Serviceability
of the equipment.
- The site conditions.
- Be capable
of making all its lifts in its standard configuration.
- 5% working
margin.
- Crawler Cranes
- Locomotive
Cranes
- Wheel-Mounted
Cranes (Multiple Control Stations)
- Wheel-Mounted
Cranes (Single Control Stations)
- Commercial
Truck-Mounted Cranes
- When selecting
a mobile crane, what are some things that its size and characteristics must
be considered against.
- Name four (4)
different types of cranes used in the industry.
Site Review
& Crane Setup
Jobsite
Conditions:
- Supporting
Surfaces
- Access &
Stability (transporting a crane)
- Working area
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
Assembly Hazards:
- Lattice Boom
Assembly & Disassembly
- Reeving the
load line
- Leveling the
crane
- Soil Conditions
must be sufficient.
- Blocking &
Cribbing should be used.
Due to the central role of cranes in construction
operations, specialists in the construction industries have cooperated in
the development of structured methods and software for crane selection.
Most of these software tools are for crane
model selection, and integrated systems that handle both crane type and model
selection are not readily available. This paper presents the crane type selection
features of Intelli Cranes, a prototype integrated crane selection tool that
assists in both crane type and crane model selection based on a set of inputs
describing the construction operation under consideration.
By using historical data and advanced artificial
intelligence computing tools such as artificial neural networks, Intelli Cranes
automates crane type selection. Crane type and crane model selection are seamlessly
integrated in a comprehensive crane selection tool, and consistency in the
selection of cranes for similar situations is increased.
Cranes
Cranes are used to aid in the construction of
heavy equipment and large buildings. They use levers and cables in order
to get materials from ground level to the upper ends of the job site.
Cranes can be bought, rented,
or leased depending upon your situation and
the length of time you will need the help of this conveyer. Their temporary
help on the job site makes a world of difference when constructing large and
heavy machinery.
There are many different types of cranes.
Before starting a project that involves a crane, it is best to educate yourself
in the many types, in order to find one that fits your needs.
Tower cranes
are generally used in the construction of tall
buildings; for they have a great reaching and lifting capability (they can
reach up to 265 feet, out to 230 feet, and lift a total of about 20 tons).
The tower crane consists of an arm lying horizontally along the top of the
tower, with one side holding up the lifting gear and another being a dead
weight to balance the material.
Hydraulic cranes
are operated by just that…hydraulics. Hydraulics
uses a fluid to get energy from one point to another. Many fluids can
be used to make this happen, the most common being oil. This energy
helps moves the pistons up and down, which exerts so much power that a hydraulic
crane can lift more than double the weight of a tower crane.
Loader cranes
are
exclusively used in order to lift material onto
a trailer. By being attached to the trailer,
it gives it leverage in order to lift heavy loads.
Telescopic cranes
are
made up of tubes inside of one another, which extend as the crane must reach
higher elevations.
Gantry cranes
are given ultra mobility because they are attached
to move on rails. These cranes which are used in the freight and railway
systems are able to carry large loads.
Stacker cranes
are used in warehouse in order to stack products
on storage racks with little ease.
Floating cranes
are used when large bodies of water are involved.
This makes work on bridges, ports, and ship salvages much easier, due to the
mobility of the crane over the water via platform.
Crawler cranes
move with a set of attached tracks in order
to move more freely on any construction site.
Overhead cranes
move along beams, which gives support to lift
very heavy materials. These cranes are usually used in manufacturing
sites.
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
Tips for safely using a crane:
- Beware of your
surroundings. When using an object of such great size as a crane,
it is imperative that you steer clear of power lines. The disruption
of power lines can not only be dangerous, but very costly should something
go wrong.
- Perform frequent
equipment assessments. Since a crane is so large, with many different
gadgets, expect that you will have mechanical problems, and take the necessary
measures to correct them. It is better to be safe than sorry.
- Educate your
operators. Before putting a worker behind a crane, be sure he is knowledgeable
in the operation of the crane, and uses caution on the job site, including
avoiding distractions.
- Never hoist
with people in the basket, or hoist more than capacity.
Industrial cranes raise, shift, and lower loads
with a projected, swinging arm or a hoisting apparatus supported on an overhead
track.
There are many different types of products.
Bench or cart-mounted cranes are designed for small workspaces and one-hand
operation. Jib cranes mount on walls or floors and consist of a horizontal
beam (jib) upon which a shuttle or hoist is mounted.
Floor or foundation-mounted jib cranes have
higher load ratings than wall-mounted cranes. A cantilevered jib crane can
incorporate full or partial rotation. Gantry cranes have a horizontal beam
and end supports or legs. Machines range in size from small, workstation cranes
to very large, heavy-duty construction cranes.
Overhead cranes or bridge cranes attach a horizontal
load-carrying beam to wall columns (overhung) or the underside of the ceiling
(under hung). Boom cranes use a structure, pole or boom to support a suspended
cable for load attachment. Tower cranes use a cantilever boom, but are designed
for very heavy-duty operations.
Mobile cranes and truck-mounted can be moved
or driven to different locations. Ship cranes and deck cranes are designed
for shipboard mounting and the loading or ships, freighters, and other maritime
vessels.
Stacker cranes are similar to bridge cranes;
however, instead of a hoist, these industrial cranes use a mast with forks
or a platform to handle unit loads.
Industrial cranes
differ in terms of product specifications, features, and applications. Performance
specifications to consider include load capacity, vertical available lifting
height, and horizontal available span.
In terms of features, products
such as tower, davit and jib cranes have a
titling boom. Machines with
a cantilevered boom
or a jib
that can be rotated with our without a load are also available. Industrial
cranes
with wheels are designed for load transport and positioning.
Typically, these machines are equipped with a
brake or stabilizing outriggers. Industrial cranes that provide
motorized motion move loads with a motor instead of manual pulling. With some
applications, an industrial pendant is used to enable an operator to actuate
lift or trolley travel.
There are many different sizes of industrial
cranes.
Small site-based cranes
are used for designed for on-site applications. Immense tower cranes
and deck cranes
are designed to move cargo containers, steel and concrete; large tools such
as acetylene torches and electrical generators; as well as a wide variety
of other building materials.
For custom or special-use cranes,
check with the manufacturer for details.
Library Crane Operations/Rigging Videos
Crane and Sling Safety
Overhead and jib boom cranes and slings are found
in almost every industry in one form or another. They are so common and used
so often that they almost become invisible - a safety hazard.
Operators forget that any misuse or actual
breakdown in equipment can be disastrous. This training program demonstrates
proper techniques for safe use of cranes and slings, and daily inspection
procedures.
Crane Safety
Part 1 - Reading a Capacity Chart 15 min.
This video has been carefully prepared to assist
operators, supervisors and riggers to understand and properly use a hydraulic
crane chart.
For many years crane charts have been misused,
misunderstood, or ignored altogether. It has been found that many crane accidents
could have been avoided through proper understanding and usage of load charts.
Part 2 - Hydraulic Cranes 20 min.
The purpose of this video is to assist operators,
supervisors and riggers in their daily business of lifting loads, using hydraulic
cranes. Safety must be the number one
priority of everyone involved with crane work.
Topics covered include: regular inspections, careful
maintenance, proper machine setup, power line awareness, pre-planning lifts,
and safe hoisting practices. Failure to follow approved practices in any of
these areas can greatly increase the chances of a costly accident.
Part 3 - Wire Rope and Rigging Safety 20 min.
The object of this video is to assist operators,
supervisors and riggers in their daily business of lifting loads using wire
rope. The most commonly made errors found throughout a number of jobsites
visited are addressed.
This program covers eight topics which were
chosen because of their relevance to safe rigging operations. Safety must
be the number one priority of every one involved in rigging and crane work.
Part 4 - Crane Accidents 20 min.
The accidents reviewed in this video were chosen
because of frequent occurrence. While most accidents appear to be the result
of operator error, further investigation often reveals that some responsibility
lies with supervision. Safe crane operations require skilful well trained
operators but management commitment to safety must be total and well publicized.
Each of these programs is accompanied by an
Instructor's manual.
Hand Operated Hoists
A video shows the proper use of chain, gear,
differential and ratchet hoists. It also discusses the proper planning, protective
equipment, and safety inspections that should be done before starting a job.
High Impact Crane Safety
This very graphic video features 5 re-enactments
of accidents involving indoor cranes. These illustrate the importance of our
following safe work practices to protect co-workers and company property when
using any type of crane.
The program shows when and how crane inspections
and pre-operational checkouts are performed, how to determine the weight of
a load and load capacity of a crane, and how to inspect and safely use slings.
Other topics covered are: lifting and moving
loads safely, use of hand signals when
operating cab-controlled cranes, and safe work procedures for crane repair.
Produced By: Canadian Learning Company
Hoists, Winches and Related Devices
The safe use of anchorage points, chain hoists,
comealongs, grip action hoists, electric chain hoists electric wire rope hoists,
pendant cranes, and base mounted winches, are discussed in this video.
Produced By: Construction Safety Association
of Ontario
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
Indoor Cranes: Safe Lifting Operations
Cranes come in all shapes and sizes, perform
a multitude of jobs and help increase productivity and making your job easier.
This program will help reduce crane accidents and breakdowns in your workplace
. You will learn about inspections and safe
operation of shop-operated power hoist equipment. Most indoor cranes are operated
by electricity or compressed air using wire rope or chain to do the lifting.
Once lifted, some loads can be positioned manually
while others will be positioned completely by the crane. Some common hoists
and cranes are jib cranes, monorails, gantry cranes and bridge cranes.
Produced By: Coastal Training Technologies
International Hand Signals
Signalers are required whenever a crane operator
does not have clear view of the machine, load, or landing area; whenever judging
distance is difficult; and whenever live electrical apparatus or wires are
in the operating area. This program presents and reviews hand signals.
Produced By: Construction Safety Association
of Ontario
Making Your Move: The Safe Use of Overhead
Cranes
This video program discusses the 10 key points
in doing a lift. Topics include: types of cranes, different parts of cranes,
checks and controls, rigging, planning the lift, doing the lift as well as samples of lifts.
Produced By: Metal Fabricating Health and Safety
Association
Power Operated Hoists
This video discusses the overhead trolley crane,
semi-gantry crane, cantilever crane, and the wall crane. The American Standards
for Crane Hand Signals are explained and demonstrated. Also emphasized are
the safety checks that should be done before the crane is used and the protective
equipment that is required.
Produced By: Industrial Training Systems Corporation
Rigging Equipment over the Floor
This video discusses the proper use of the equipment
used for moving a load across the floor. Procedures for the raising and lowering
of a load with jacks are discussed as are the use of blocks, skids and a forklift.
Produced By: Industrial Training Systems Corporation
Rigging: Wire Rope Slings
This video discusses different types of wire
rope slings and their proper use. Safety procedures and required protective
equipment are also described.
Produced By: Industrial Training Systems Corporation
Crane and Sling Safety
Overhead and jib boom cranes and slings are
found in almost every industry in one form or another. They are so common
and used so often that they almost become invisible - a safety hazard. Operators
forget that any misuse or actual breakdown in equipment can be disastrous.
This training program demonstrates proper techniques for safe use of cranes
and slings, and daily inspection procedures.
Produced By: Summit Training
Systems
Crane Safety
Part 1 - Reading a Capacity Chart 15 min.
This video has been carefully prepared to assist
operators, supervisors and riggers to understand and properly use a hydraulic
crane chart. For many years crane charts
have been misused, misunderstood, or ignored altogether.
It has been found that many crane accidents could have been avoided through
proper understanding and usage of load charts.
Part 2 - Hydraulic Cranes 20 min.
The purpose of this video is to assist operators,
supervisors and riggers in their daily business of lifting loads, using hydraulic
cranes. Safety must be the number one priority of everyone involved with crane
work. Topics covered include: regular inspections, careful maintenance, proper
machine setup, power line awareness, pre-planning lifts, and safe hoisting
practices. Failure to follow approved practices in any of these areas can
greatly increase the chances of a costly accident.
Part 3 - Wire Rope and Rigging Safety 20 min.
The object of this video is to assist operators,
supervisors and riggers in their daily business of lifting loads using wire
rope. The most commonly made errors found throughout a number of jobsites
visited are addressed.
This program covers eight topics which were
chosen because of their relevance to safe rigging operations. Safety must
be the number one priority of every one involved in rigging and crane work.
Part 4 - Crane Accidents 20 min.
The accidents reviewed in this video were chosen
because of frequent occurrence. While most accidents appear to be the result
of operator error, further investigation often reveals that some responsibility
lies with supervision. Safe crane operations require skilful well trained
operators but management commitment to safety must be total and well publicized.
Each of these programs is accompanied by an
Instructor's manual.
Produced By: Crane Safety Ltd.
Hand Operated Hoists
This video shows the proper use of chain, gear,
differential and ratchet hoists. It also discusses the proper planning, protective
equipment, and safety inspections that should be done before starting a job.
Produced By: Marshall Maintenance
High Impact Crane Safety
This very graphic video features 5 re-enactments
of accidents involving indoor cranes. These illustrate the importance of our
following safe work practices to protect co-workers and company property when
using any type of crane. The program shows when and how crane inspections and pre-operational checkouts
are performed, how to determine the weight of
a load and load capacity of a crane, and how to inspect and safely use slings.
Other topics covered are: lifting and moving loads safely, use of hand signals
when operating cab-controlled cranes, and safe work procedures for crane repair.
Produced By: Canadian Learning Company
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
Hoists, Winches and Related Devices
The safe use of anchorage points, chain hoists,
come longs, grip action hoists, electric chain hoists electric wire rope hoists,
pendant cranes, and base mounted winches, are discussed in this video.
Produced By: Construction Safety Association
of Ontario
Indoor Cranes: Safe Lifting Operations
Cranes come in all shapes and sizes, perform a
multitude of jobs and help increase productivity and making your job easier.
This program will help reduce crane accidents and breakdowns in your workplace.
You will learn about inspections and safe operation
of shop-operated power hoist equipment. Most indoor cranes are operated by
electricity or compressed air using wire rope or chain to do the lifting.
Once lifted, some loads can be positioned manually while others will be positioned
completely by the crane. Some common hoists and cranes are jib cranes, monorails,
gantry cranes and bridge cranes.
Produced By: Coastal Training Technologies
International Hand Signals
Signalers are required whenever a crane operator
does not have clear view of the machine, load, or landing area; whenever judging
distance is difficult; and whenever live electrical apparatus or wires are
in the operating area. This program presents and reviews hand signals.
Produced By: Construction Safety Association
of Ontario
Making Your Move: The Safe Use of Overhead
Cranes
This video program discusses the 10 key points
in doing a lift. Topics include: types of cranes, different parts of cranes,
checks and controls, rigging, planning the lift, doing the lift as well as
samples of lifts.
Produced By: Metal Fabricating Health and Safety
Association
Power Operated Hoists
This video discusses the overhead trolley crane,
semi-gantry crane, cantilever crane, and the wall crane. The American Standards
for Crane Hand Signals are explained and demonstrated. Also emphasized are
the safety checks that should be done before the crane is used and the protective
equipment that is required.
Produced By: Industrial Training Systems Corporation
Rigging Equipment over the Floor
This video discusses the proper use of the
equipment used for moving a load across the floor. Procedures for the raising
and lowering of a load with jacks are discussed as are the use of blocks,
skids and a forklift.
Produced By: Industrial Training Systems Corporation
Rigging: Wire Rope Slings
This video discusses different types of wire
rope slings and their proper use. Safety procedures and required protective
equipment are also described.
Produced By: Industrial Training Systems Corporation
Crane and Sling Safety
Overhead and jib boom cranes and slings are found
in almost every industry in one form or another. They are so common and used
so often that they almost become invisible - a safety hazard. Operators forget
that any misuse or actual breakdown in equipment can be disastrous. This training
program demonstrates proper techniques for safe use of cranes
and slings, and daily inspection procedures.
Produced By: Summit Training
Systems
Crane Safety
Part 1 - Reading a Capacity Chart 15 min.
This video has been carefully prepared to assist
operators, supervisors and riggers to understand and properly use a hydraulic
crane chart. For many years crane charts have been misused, misunderstood,
or ignored altogether. It has been found that many crane accidents could have
been avoided through proper understanding and usage of load charts.
Part 2 - Hydraulic Cranes 20 min.
The purpose of this video is to assist operators,
supervisors and riggers in their daily business of lifting loads, using hydraulic
cranes. Safety must be the number one priority of everyone involved with crane
work.
Topics covered include: regular inspections,
careful maintenance, proper machine setup, power line awareness, pre-planning
lifts, and safe hoisting practices. Failure to follow approved practices in
any of these areas can greatly increase the chances of a costly accident.
Part 3 - Wire Rope and Rigging Safety 20 min.
The object of this video is to assist operators,
supervisors and riggers in their daily business of lifting loads using wire
rope. The most commonly made errors found throughout a number of jobsites
visited are addressed. This program covers eight topics which were chosen
because of their relevance to safe rigging operations. Safety must be the
number one priority of every one involved in rigging and crane work.
Part 4 - Crane Accidents 20 min.
The accidents reviewed in this video were chosen
because of frequent occurrence. While most accidents appear to be the result
of operator error, further investigation often reveals that some responsibility
lies with supervision. Safe crane operations require skilful well trained
operators but management commitment to safety must be total and well publicized.
Each of these programs is accompanied by an
Instructor's manual.
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
Produced By: Crane Safety Ltd.
Hand Operated Hoists
This video shows the proper use of chain, gear, differential and ratchet hoists.
It also discusses the proper planning, protective
equipment, and safety inspections that should be done before starting a job.
Produced By: Marshall Maintenance
High Impact Crane Safety
This very graphic video features 5 re-enactments
of accidents involving indoor cranes. These illustrate the importance of our
following safe work practices to protect co-workers and company property when
using any type of crane. The program shows when and how crane inspections
and pre-operational checkouts are performed, how to determine the weight of
a load and load capacity of a crane, and how to inspect and safely use slings.
Other topics covered are: lifting and moving loads safely, use of hand signals
when operating cab-controlled cranes, and safe work procedures for crane repair.
Produced By: Canadian Learning Company
Hoists, Winches and Related Devices
The safe use of anchorage points, chain hoists,
come longs, grip action hoists, electric chain hoists electric wire rope hoists,
pendant cranes, and base mounted winches, are discussed in this video.
Produced By: Construction Safety Association
of Ontario
Indoor Cranes: Safe Lifting Operations
Cranes come in all shapes and sizes, perform
a multitude of jobs and help increase productivity and making your job easier.
This program will help reduce crane accidents and breakdowns in your workplace.
You will learn about inspections and safe operation
of shop-operated power hoist equipment. Most indoor cranes are operated by
electricity or compressed air using wire rope or chain to do the lifting.
Once lifted, some loads can be positioned manually while others will be positioned
completely by the crane. Some common hoists and cranes are jib cranes, monorails,
gantry cranes and bridge cranes.
Produced By: Coastal Training Technologies
International Hand Signals
Signalers are required whenever a crane operator
does not have clear view of the machine, load, or landing area; whenever judging
distance is difficult; and whenever live electrical apparatus or wires are
in the operating area. This program presents and reviews hand signals.
Produced By: Construction Safety Association
of Ontario
Making Your Move: The Safe Use of Overhead
Cranes
This video program discusses the 10 key points
in doing a lift. Topics include: types of cranes, different parts of cranes,
checks and controls, rigging, planning the lift, doing the lift as well as
samples of lifts.
Produced By: Metal Fabricating Health and Safety
Association
Power Operated Hoists
This video discusses the overhead trolley crane,
semi-gantry crane, cantilever crane, and the wall crane. The American Standards
for Crane Hand Signals are explained and demonstrated. Also emphasized are
the safety checks that should be done before the crane is used and the protective
equipment that is required.
Produced By: Industrial Training Systems Corporation
Rigging Equipment over the Floor
This video discusses the proper use of the
equipment used for moving a load across the floor. Procedures for the raising
and lowering of a load with jacks are discussed as are the use of blocks,
skids and a forklift.
Produced By: Industrial Training Systems Corporation
Rigging: Wire Rope Slings
This video discusses different types of wire
rope slings and their proper use. Safety procedures and required protective
equipment
are also described.
Produced By: Industrial Training Systems Corporation
Crane
A crane isny of a diverse group of machines
that lift and move heavy objects. Cranes differ
from hoists, elevators, and other devices intended for vertical lifting, and
from conveyors, which continuously lift or carry bulk materials such as grain
or coal.
Cranes have been widely used only since the
introduction of steam engines, internal-combustion engines, and electric motors
in the 19th century. They range in type and function from the largest derrick
cranes to small, mobile truck cranes. Most derrick cranes can lift 5 – 250
tons (4.5 – 230 metric tons).
Floating cranes, built on barges for constructing
bridges or salvaging sunken objects, may be able to lift 3,000 tons (2,700
metric-tons). Small truck cranes are mounted on heavy, modified trucks; they
make up in mobility and ease of transport what they lack in hoisting capacity.
A crane is a mechanical lifting device equipped
with hoists, wire ropes and sheaves that can be used both to lift and lower
materials and to move them horizontally.
Cranes are commonly employed in the construction
industry and in manufacturing heavy equipment. Construction cranes have either
telescoping, lattice or articulating booms. Telescoping boom cranes would
include the Industrial, Rough Terrain, Truck Mounted, All Terrain and City
Cranes.
Lattice boom cranes would include the Crawler
Mounted, Truck Mounted, Ringer Mounted and Hammerhead and Luffing Boom tower
cranes. Articulating boom cranes are mounted on commercial trucks and can
have telescoping boom sections and hoists. Railroad Track and Floating Cranes
can be either telescoping, lattice or articulating boom. Manufacturing cranes
would include the Mono-Rails, Bridge, Polar, Gantry and Stacker Cranes.
History of cranes
Ancient Greek cranes
The crane for lifting heavy loads was invented
by the ancient Greeks in the late 6th century BC. The archaeological record
shows that no later than c.515 BC distinctive cuttings for both lifting tongs
and lewis irons begin to appear on stone blocks of Greek temples.
Since these holes point at the use of a lifting
device, and since they are to be found either above the centre of gravity
of the block, or in pairs equidistant from a point over the centre of gravity,
they are regarded by archaeologists as the positive evidence required for
the existence of the crane.
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
The introduction of the winch
and pulley hoist soon leads to a widespread replacement of ramps as the main
means of vertical motion. For the
next two hundred years, Greek building sites witnessed a sharp drop in the
weights handled, as the new lifting technique made the use of several smaller
stones more practical than of fewer larger ones.
In contrast to the archaic period with its
tendency to ever-increasing block sizes, Greek temples of the classical age
like the Parthenon invariably featured stone blocks weighting less than 15-20
tons. Also, the practice of erecting large monolithic columns was practically
abandoned in favor of using several column drums.
Although the exact circumstances of the shift
from the ramp to the crane technology remain unclear, it has been argued that
the volatile social and political conditions of Greece were more suitable
to the employment of small, professional construction teams than of large
bodies of unskilled labor, making the crane more preferable to the Greek polis
than the more labor-intensive ramp which had been the norm in the autocratic
societies of Egypt or Assyria. .
The first unequivocal literary evidence for
the existence of the compound pulley system appears in the Mechanical Problems
(Mech. 18, 853a32-853b13) attributed to Aristotle (384-322 BC), but perhaps
composed at a slightly later date.
Around the same time, block sizes at Greek temples
began to match their archaic predecessors again, indicating that the more
sophisticated compound pulley must have found its way to Greek construction
sites by then.
Ancient Roman cranes
Reconstruction of a 10.4m high Roman Polyspastos
at Bonn,
Germany.
The heyday of crane in ancient times came under
the Roman Empire,
when construction activity soared and buildings reached enormous dimensions.
The Romans adopted the Greek crane and developed it further.
We are relatively well informed about their
lifting techniques thanks to rather lengthy accounts by the engineers Vitruvius
(De Architectura 10.2, 1-10) and Heron of Alexandria (Mechanica 3.2-5). There
are also two surviving reliefs of Roman tread wheel cranes offering pictorial
evidence, with the Haterii tombstone from the late first century AD being
particularly detailed.
The simplest Roman crane, the
Trispastos, consisted of a single-beam jib,
a winch, a rope, and a block containing three pulleys. Having thus a mechanical
advantage of 3:1, it has been calculated that a single man working the winch
could raise 150 kg (3 pulleys x 50 kg = 150), assuming that 50 kg represent
the maximum effort a man can exert over a longer time period.
Heavier crane types featured five pulleys (Pentaspastos)
or, in case of the largest one, a set of three by five pulleys (Polyspastos)
and came with two, three or four masts, depending on the maximum load. The
Polyspastos, when worked by four men at both sides of the winch, could already
lift 3000 kg (3 ropes x 5 pulleys x 4 men x 50 kg = 3000 kg). In case the
winch was replaced by a tread wheel, the maximum load even doubled to 6000
kg at only half the crew, since the tread wheel possesses a much bigger mechanical
advantage due to its larger diameter.
This meant that, in comparison to the construction
of the Egyptian Pyramids, where about 50 men were needed to move a 2.5 ton
stone block up the ramp (50 kg per person), the lifting capability of the
Roman Polyspastos proved to be 60 times higher (3000 kg per person).
However, numerous extant Roman buildings which
feature much heavier stone blocks than those handled by the Polyspastos indicate
that the overall lifting capability of the Romans went far beyond that of
any single crane.
At the temple
of Jupiter at
Baalbek,
for incidence, the architraves blocks weigh up to 60 tons each, and the corner
cornices blocks even over 100 tons, all of them raised to a height of ca.
19 m above the ground. [3] In Rome,
the capital block of Trajan's Column weighs 53.3 tons which had to be lifted
at a height of ca. 34 m.
It is assumed that Roman engineers accomplished
lifting these extraordinary weights by two measures: First, as suggested by
Heron, a lifting tower was set up, whose four masts were arranged in the shape
of a quadrangle with parallel sides, not unlike a siege tower, but with the
column in the middle of the structure (Mechanica 3.5).
] Second, a multitude of capstans were placed
on the ground around the tower, for, although having a lower leverage ratio
than tread wheels, capstans could be set up in higher numbers and run by more
men (and, moreover, by draught animals).
This use of multiple capstans is also described
by Ammianus Marcellinus (17.4.15) in connection with the lifting of the Lateranense
obelisk in the Circus Maximus (ca. 357 AD). The maximum lifting capability
of a single capstan can be established by the number of lewis iron holes bored
into the monolith. In case of the Baalbek architrave
blocks, which weigh between 55 and 60 tons, eight extant holes suggest an
allowance of 7.5 ton per lewis iron that is per capstan.
Lifting such heavy weights
in a concerted action required a great amount of coordination between the
work groups applying the force to the capstans.
Medieval cranes
During the High Middle Ages the tread wheel
crane was reintroduced on a large scale after the technology had fallen into
disuse in Western Europe with
the demise of the Western Roman Empire.
The earliest reference to a tread wheel (magna
rota) reappears in archival literature in France about
1225,[10] followed by an illuminated depiction in a manuscript of probably
also French origin dating to 1240.
In navigation, the earliest uses of harbor
cranes are documented for Utrecht in
1244, Antwerp in
1263, Brugge in 1288 and Hamburg in
1291,[11] while in England the
tread wheel is not recorded before 1331.[12]
Generally, vertical transport was done safer
and cheaper by cranes than by customary methods. Typical areas of application
were harbors, mines, and, in particular, building sites where the tread wheel
crane played a pivotal role in the construction of the lofty Gothic cathedrals.
Nevertheless, both archival and pictorial sources
of the time suggest that newly introduced machines like tread wheels or wheelbarrows
did not completely replace more labor-intensive methods like ladders, hods
and handbarrows. Rather, old and new machinery continued to coexist on medieval
construction sites and harbors.
Apart from tread wheels, medieval depictions
also show cranes to be powered manually by windlasses with radiating spokes,
cranks and by the 15th century also by windlasses shaped like a ship's wheel.
To smooth out irregularities of impulse and get over 'dead-spots' in the lifting
process flywheels are known to be in use as early as 1123.
Origins
The exact process by which the tread wheel crane
was reintroduced is not recordedalthough its return to construction sites
has undoubtedly to be viewed in close connection with the simultaneous rise
of Gothic architecture. The reappearance
of the tread wheel crane may have resulted from a technological development
of the windlass from which the tread wheel structurally and mechanically evolved.
Alternatively, the medieval tread wheel may
represent a deliberate reinvention of its Roman counterpart drawn from Vitruvius'
De architectura which was available in many monastic libraries. Its reintroduction
may have been inspired, as well, by the observation of the labor-saving qualities
of the waterwheel with which early tread wheels shared many structural similarities.
Structure and placement
The medieval tread wheel was a large wooden
wheel turning around a central shaft with a tread way wide enough for two
workers walking side by side. While the earlier 'compass-arm' wheel had spokes
directly driven into the central shaft, the more advanced 'clasp-arm' type
featured arms arranged as chords to the wheel rim, giving the possibility
of using a thinner shaft and providing thus a greater mechanical advantage.
Contrary to a popularly held belief, cranes
on medieval building sites were neither placed on the extremely lightweight
scaffolding used at the time nor on the thin walls of the Gothic churches
which were incapable of supporting the weight of both hoisting machine and
load.
Rather, cranes were placed in the initial stages
of construction on the ground, often within the building. When a new floor
was completed, and massive tie beams of the roof connected the walls, the
crane was dismantled and reassembled on the roof beams from where it was moved
from bay to bay during construction of the vaults.
] Thus, the crane ‘grew’ and ‘wandered’ with
the building with the result that today all extant construction cranes in
England are found in church towers above the vaulting and below the roof,
where they remained after building construction for bringing material for
repairs aloft.[18] Less frequently, medieval illuminations also show cranes
mounted on the outside of walls with the stand of the machine secured to putlogs.
Mechanics
and operation
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
In contrast to modern cranes, medieval cranes
and hoists - much like their counterparts in Greece and
Rome -
were primarily capable of a vertical lift, and not used to move loads for
a considerable distance horizontally as well. .
Accordingly, lifting work was organized at the workplace in
a different way than today. In building construction,
for example, it is assumed that either the crane lifted the stone blocks from
the bottom directly into place, or from a place opposite the centre of the
wall from where it could deliver the blocks for two teams working at each
end of the wall.
Additionally, the crane master who usually
gave orders at the tread wheel workers from outside the crane was able to
manipulate the movement laterally by a small rope attached to the load.
Slewing cranes which allowed a rotation of
the load and were thus particularly suited for dockside work appeared as early
as 1340.[22] While ashlar blocks were directly lifted by sling, Lewis or devil's
clamp (German Teufelskralle), other objects were placed before in containers
like pallets, baskets, wooden boxes or barrels.
It is noteworthy that medieval cranes rarely featured
ratchets or brakes to forestall the load from running backward. This curious
absence is explained by the high friction force exercised by medieval tread
wheels which normally prevented the wheel from accelerating beyond control.
Harbor cranes
According to the “present state of knowledge”
unknown in antiquity, stationary harbor cranes are considered a new development
of the middle Ages. The typical harbor crane was a pivoting structure equipped
with double tread wheels. These cranes were placed docksides for the loading
and unloading of cargo where they replaced or complemented older lifting methods
like see-saws, winches and yards.
Two different types of harbor cranes can be
identified with a varying geographical distribution: While gantry cranes which
pivoted on a central vertical axle were commonly found at the Flemish and
Dutch coast side, German sea and inland harbors typically featured tower cranes
where the windlass and tread wheels were situated in a solid tower with only
jib arm and roof rotating.
Interestingly, dockside cranes were not adopted
in the Mediterranean region and the highly developed Italian ports where authorities
continued to rely on the more labor-intensive method of unloading goods by
ramps beyond the Middle Ages.
Unlike construction cranes where the work speed
was determined by the relatively slow progress of the masons, harbor cranes
usually featured double tread wheels to speed up loading. The two tread wheels
whose diameter is estimated to be 4 m or larger were attached to each side
of the axle and rotated together.
Today, according to one survey,
fifteen tread wheel harbor cranes from pre-industrial times are still extant
throughout Europe. Beside these stationary cranes, floating cranes which could be
flexibly deployed in the whole port basin came into use by the 14th century.
.
Crane operator training and
certification
USA
The National Association of Heavy Equipment
Training Schools and CCO are the primary educational certification bodies
for the crane industry in the USA.
Types of cranes
Railroad cranes
A railroad crane is a crane that is mounted
on a railroad car or on a flatcar.
Mobile
crane
The most basic type of crane consists of a
steel truss or telescopic boom mounted on a mobile platform, which may be
rail, wheeled (including "truck" carriers) or caterpillar tracks.
The boom is hinged at the bottom, and can be raised and lowered by cables
or by hydraulic cylinders. A hook is suspended from the top of the boom by
wire rope and sheaves.
The wire ropes are operated by whatever prime
movers the designers have available, operating through a variety of transmissions.
Steam engines, electric motors and internal combustion engines (IC) have all
been used. Older cranes' transmissions tended to be clutches.
This was later modified when using IC engines
to match the steam engines "max torque at zero speed" characteristic
by the addition of a hydrokinetic element culminating in controlled torque
converters. The operational advantages of this arrangement can now be achieved
by electronic control of hydrostatic drives, which for size and other considerations
is becoming standard.
Some examples of this type of crane can be
converted to a demolition crane by adding a demolition ball or to an earthmover
by adding a clamshell bucket or a dragline and scoop, although design details
can limit their effectiveness.
According to the “present state of knowledge”
unknown in antiquity, stationary harbor cranes are considered a new development
of the middle Ages.
The typical harbor crane was a pivoting structure equipped with
double tread wheels. These cranes were placed
docksides for the loading and unloading of cargo where they replaced or complemented
older lifting methods like see-saws, winches and yards.
Two different types of harbor cranes can be
identified with a varying geographical distribution: While gantry cranes which
pivoted on a central vertical axle were commonly found at the Flemish and
Dutch coast side, German sea and inland harbors typically featured tower cranes
where the windlass and tread wheels were situated in a solid tower with only
jib arm and roof rotating.
Interestingly, dockside cranes were not adopted
in the Mediterranean region and the highly developed Italian ports where authorities
continued to rely on the more labor-intensive method of unloading goods by
ramps beyond the Middle Ages.[26]
Unlike construction cranes where the work speed
was determined by the relatively slow progress of the masons, harbor cranes
usually featured double tread wheels to speed up loading. The two tread wheels
whose diameter is estimated to be 4 m or larger were attached to each side
of the axle and rotated together.
Today, according to one survey, fifteen tread
wheel harbor cranes from pre-industrial times are still extant throughout
Europe.
Beside these stationary cranes, floating cranes
which could be flexibly deployed in the whole port basin came into use by
the 14th century.
USA
The National Association of Heavy Equipment
Training Schools and CCO are the primary educational certification bodies
for the crane industry in the USA.
A railroad crane is a crane that is mounted
on a railroad car or on a flatcar.
The most basic type of crane consists of a
steel truss or telescopic boom mounted on a mobile platform, which may be
rail, wheeled (including "truck" carriers) or caterpillar tracks.
The boom is hinged at the bottom, and can be raised and lowered by cables
or by hydraulic cylinders.
A hook is suspended from the
top of the boom by wire rope and sheaves. The
wire ropes are operated by whatever prime movers the designers have available,
operating through a variety of transmissions.
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
|
Steam engines, electric motors and internal combustion
engines (IC) have all been used. Older cranes' transmissions tended to be
clutches. This was later modified when using IC engines to match the steam
engines "max torque at zero speed" characteristic by the addition
of a hydrokinetic element culminating in controlled torque converters. The
operational advantages of this arrangement can now be achieved by electronic
control of hydrostatic drives, which for size and other considerations is
becoming standard.
Some examples of this type of crane can be
converted to a demolition crane by adding a demolition ball or to an earthmover
by adding a clamshell bucket or a dragline and scoop, although design details
can limit their effectiveness.
The tower crane is a modern form of balance
crane. Fixed to the ground, tower cranes often give the best combination
of height and lifting capacity and are used in the construction
of tall buildings.
(more
on crane accident safety at OSHA)
To save space and to provide stability the
vertical part of the crane is often braced onto the completed structure which
is normally the concrete lift shaft in the center of the building. A horizontal
boom is balanced asymmetrically across the top of the tower.
Its short arm carries a counterweight of concrete
blocks, and its long arm carries the lifting gear. The crane operator either
sits in a cabin at the top of the tower or controls the crane by radio remote
control from the ground, usually standing near the load. In the first case
the operator's cabin is located at the top of the tower just below the horizontal
boom.
The boom is mounted on a slewing bearing and
is rotated by means of a slewing motor. The lifting hook is operated by a
system of sheaves.
A tower crane is usually assembled by a telescopic
crane of smaller lifting capacity but greater height and in the case of tower
cranes that have risen while constructing very tall skyscrapers, a smaller
crane will sometimes be lifted to the roof of the completed tower to dismantle
the tower crane afterward.
A self-assembling tower crane has been demonstrated,
which lifts itself off the ground using jacks, allowing the next section of
the tower to be inserted at ground level.
Truck-mounted crane
A crane mounted on truck carrier which provides
the mobility for the crane. Outriggers that extend horizontally and vertically
are used to level and stabilize the crane for hoisting.
Almost invariably called a "Hiab"
by its operators, this is a hydraulically-powered articulated arm fitted to
a trailer, used to move goods onto or off of the trailer. Unlike most cranes the operator must
move around to be able to view his load; hence he will have a portable cabled
or radio linked control system.
The numerous jointed sections can be folded into
a small space when the crane is not in use. One or more of the sections may
be telescopic. Often the crane will have a degree of automation and be able
to unload or stow itself without an operator's instruction.
Rolloader crane
This is a loader crane mounted on a chassis
with wheels. This chassis can ride on the trailer. Because the crane can move
on the trailer, it can be a light crane, so the trailer is allowed to transport
more goods.
Rough terrain crane
A crane mounted on an undercarriage with four
rubber tires that is designed for pick-and-carry operations and for off-road
and "rough terrain" applications. Outriggers that extend horizontally
and vertically are used to level and stabilize the crane for hoisting.
These telescopic cranes are single-engine machines
where the same engine is used for powering the undercarriage as is used for
powering the crane, similar to a crawler crane. However, in a rough terrain
crane, the engine is usually mounted in the undercarriage rather than in the
upper, like the crawler crane.
Crawler
crane
A crawler is a crane mounted on an undercarriage
with a set of tracks that provide for the stability and mobility of the crane.
Crawler cranes have both advantages and disadvantages depending on their intended
use.
The main advantage of a crawler
is that they can move on site and perform lifts with very little set-up, as the crane is stable on its tracks with no
outriggers. In addition, a crawler crane is capable of moving with a load.
The main disadvantage of a crawler crane is that
they are very heavy, and cannot easily be moved from one job site to the next
without significant expense. Typically, a large crawler must be disassembled
or moved by barge in order to be transported.
NOTE: GANTRY CRANES, BRIDGE
CRANES, JIB CRANES AND AUTO CRANES' CRANE OPERATORS SHOULD
HAVE EXPERIENCE TO MOVE TO AN OVERHEAD BRIDGE CRANE. NATIONAL
CRANE OVERHEAD CRANES AND CRANE TRUCKS REQUIRED ATTENDANCE
AT A CRANE SCHOOL TO PREVENT CRANE ACCIDENT. USED CRANES FOR
SALE CAN BE FOUND LOCALLY (SEE ABOVE CITY LIST) FOR THE TEREX
CRANE, PORTABLE CRANE, CRANE HOISTS (HOIST CRANE), AND TRUCK
CRANE, AS WELL AS OTHER CRANE EQUIPMENT. CAN BE SENT AT DISCOUNT
PRICES. YOU CAN BUY NOW OR RENT. EQUIPMENT IS ON SALE WITH
A PRICE COST OF LOW DOLLARS AND CENTS. REFUND IS OFTEN IN
CASH IF NOT SATISFIED. IF YOU DECIDE TO BUILD YOUR OWN (DIY)
YOU CAN OFTEN UTILIZE LEFTOVERS FROM FACTORY SECONDS, SURPLUS
, DISCONTINUED MERCHANDISE, GARAGE CLEAN OUTS, WAREHOUSE CLEANOUT,
RETAIL CLOSEOUTS, ITEMS FROM FACTORY REJECTS, OUT OF BUSINESS
SALES & FACTORY CLEAN OUTS. FINALLY, DON'T OVERLOOK CLOSEOUTS!
WHEN BUYING ONLINE, PAYPAL, MASTERCARD, DISCOVER, AMERICAN
EXPRESS, AND VISA ARE ALMOST ALWAYS ACCEPTED. RENTALS OF FIRST
AND SECOND QUALITY ARE POSSIBLE. SPECIAL PRICES ALWAYS APPEAR
AT CLOSEOUT AND DISTRESSED SALES. WE DO NOT BROKER OR BUY
THESE ITEMS FOR RESALE. ORDINARILY, THE SALE PRICE IS FINAL
FOR USED EQUIPMENT, REPOSSESSIONS, JUNK, INSURANCE SALVAGE
OR FREIGHT SALVAGE. DISTRESSED MERCHANDISE CAN BE A GOOD SOURCE
OF GENERAL SUPPLY FOR INDUSTRIAL MATERIALS AND PRODUCTS. AGAIN,
BUY NOW, BUY NOW, BUY NOW. THE SALE PRICE MAY NEVER BE LOWER.
SAVE $ $ $ $ $ $ $ $ $ $.
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