20 ton Freestanding Overhead Crane System

20 ton Freestanding Overhead Crane System & 2 ton Freestanding Overhead Crane System

Crane-Tec was recently contracted to supply multiple overhead cranes and runway systems to a leading fabrication and engineering firm in Indiana.  The customer had purchased a spec building that wasn’t designed for overhead cranes and came to Crane-Tec for their overhead crane solution.  Crane-Tec worked with the customer and the General Contractor to designed a 20 ton free-standing runway system to accommodate (2) 10 ton 70+ foot span single box girder overhead cranes and multiple 2 ton jib cranes.


Crane-Tec worked closely with the customers General Contractor and assisted in the design of the necessary crane footers.  Crane-Tec engineers design and completely independent freestanding 20 ton overhead crane system that is capable of supporting 2 ton jib cranes.  Crane-Tec also designed and installed a 2 ton freestanding workstation crane that utilized 4 ton center bay columns so the owner can easily add a 2nd 2 ton system in the future.


All the crane and structural steel were installed successfully and on-time.  Electronic eyes were installed on the 10 ton cranes to keep them from touching and bridge travel limit switched were instated on the runway to reduce impact of cranes into the end-stops.

The customer’s facility is now up and running and the cranes have become an iatrical part of their fabrication process.


Safety instructions part 4

Safety Instructions for Finishing Work with the Hoist

  1. Raise the empty hook or loading device high enough to avoid it causing a hazard to traffic, but not to the top safety limit.
  2. Leave all the controls in the O- position
  3. Press the emergency stop button to open the main contractor.
  4. Turn off the safety switches for control current and main current.
  5. Close any mechanical brakes such as rail clamps, etc.
  6. Inform your foreman of any defects you have noticed.
  7. Inform  the next operator of all abnormalities in equipment operation you have noticed.

Safety Instructions for Servicing the Hoist

  1. Carry out regular inspections and preventative maintenance in compliance with the instructions. Keep a record of inspections and servicing. Regular servicing and inspection procedures are necessary for the safe and efficient operation of the hoist. In uncertain or unusual cases, contact the supplier of the hoist.
  2. Pay special attention to the operation of the brake and limit switches, and to the condition of the hook, rope and pushbutton controller. It is essential that safety devices (overload protectors, limit switches, etc.) work correctly and are in full operating order because they safeguard against human error.
  3. Use trained servicing personnel authorized by the manufacturer of the hoist for servicing the hoist. The person servicing the hoist must be competent for the task and must be familiar with the servicing and inspection instructions.
  4. Use only genuine spare parts approved by the manufacturer of the hoist.
  5. Any modifications or additions made to the hoist’s structures or performance values must first be discussed with the supplier of the hoist.
  6. Any inspections and repair operations carried out on the hoist after an overload or collision must be discussed with the supplier of the hoist.


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Part 3. Lifting the Load- Things that you do not want to do

  1. Do not lift people on the hook or load. Lifting people with a hoist is prohibited unless the hoist is designed and manufactured for that purpose(this must always be agreed with the supplier of the hoist).  Do not go under the hook or a load. Do not move the hook or load over a person. A load must never be lifted in a way that can injure a person if the load drops.Do not operate the hoist if you know that medication, an illness, or other such handicap impairs your alertness or working ability.
  2.  Do not lift a load that is fastened to its base or that is heavier than the maximum permissible load for the hoist or lifting accessories. A jerking or static load can cause an overload. A hoist may only be used for those loads and load combinations, and at those speeds, for which the hoist has been designed and manufactured.  Raise the load high enough to prevent it from hitting objects during travel. However, do not raise it higher than is necessary for the situation. Do not raise the hook to the top safety limit.
  3. During hoisting and travel motion, ensure that the hook, the load, and the crane and its moving parts do not collide with objects or people.  If the hoist is provided with a horn, sound the horn when you move the load in the vicinity of people who are not paying attention to the moving load.  Do not move the load until you have received a signal from the person attaching the load to the hook or lifting appliance.  Do not use the overload protection for weighing the load.
  4. Stop all hoisting and travel motions before the safety limit switches.  Do not adjust or bypass the limit switches or warning devices in order to go past motion limits. Do not use the hoist if the limit switches are inoperative.  If the manually-adjusted backup limit switch in the hoist has triggered, call a serviceman to the hoist and ask him to determine why the normal safety limit switch did not function.  Do not use the hoisting rope as a lifting lug.
  5. Do not use the hoist if there are visible defects in; or damage to, the hoist, the hoisting rope, or any other hoist structure or hoist function. Stop operating the hoist if it operates abnormally (for example, a high noise level, uneven starting, or malfunctions).Using faulty equipment is strictly prohibited.  If defects have been noticed in the hoist, carry out the necessary inspections and servicing. Ensure that the hoist operates properly before you start to use it again.  Do not use the limit switches to stop the motions of the hoist. Hoist motions must be stopped with the pushbutton controller or other control device intended for the purpose.
  6. Use the proper pushbuttons intended for controlling the hoist. If you feel you are losing control of the hoist motions, press the emergency stop button. In a potentially dangerous situation all hoist motions can be stopped by pressing the emergency stop button, but do not use the emergency stop function unnecessarily. Ensure that it is safe to re-commence working after the emergency stop button has been pressed.  Avoid short, jerky motions. Unnecessary short starts can cause the hoisting motor to overheat quickly. The last controller step is for normal drive. The intermediate steps are normally used for short durations only. Do not switch the controller back and forth unnecessarily because it causes wear. Avoid violent collisions into other hoists or against the buffers.
  • Do not leave a suspended load unattended.
  • Do not lower the hook so far that the ropes become slack.
  • Do not pull a load from the side. Lower the load with the ropes perpendicular.
  • Do not use hoist motions to remove the load from the hook.
  • Do not weld on a hook that is not isolated. Do not fasten a welding electrode to the hoisting rope.
  • Do not change the size of fuses. A qualified electrician should carry out all electrical work.


Part 2 Lifting the Load

In order to get the maximum lifetime out of a hoist, you want to be sure that you are using it correctly. Using the hoist for projects out of the hoist group classification for which it was designed changes the lifetime of the product.  Before hoisting a load, be sure to determine a safe and effective path for it to travel to ensure that the load will not collide against objects or people. Also,  check that no servicemen or unauthorized persons are on the crane and that the rails and power cables are clear of obstructing objects.  Before hoisting, check that the hoisting devices are securely positioned on the bearing surface of the hook and that the safety catch on the hook is closed.

Next, you want to ensure that the load’s mass center is on the center line of the hook forging so that the load does not bend the hook neck.  Make sure that the force is applied only to the hook’s bearing surface (the lowest point of the hook) because if  force is applied to other parts of the hook it will cause undesired stresses.  Forces on ramshorn hooks have to be equal on both bearing surfaces.  Before hoisting, check that the load is balanced and safely fastened at the lifting points and also be sure that the load cannot slide, slip or detach itself when suspended.

In addition, you need to confirm that the ropes are perpendicular and that the hoist is positioned perpendicularly above the load to be lifted.  A load must not be hoisted or dragged along the ground in a way that causes side pull on the roping unless the hoist is designed and manufactured for this purpose.  When using a lifting accessory (sling, belt, etc.), always follow the instructions provided by the lifting accessory manufacturer. Finally, if two cranes are needed to handle a load, a balancing beam must be used to equalize the loading.  Combined hoisting with two cranes must be supervised by a foreman knowledgeable about cranes or by a crane specialist who is in charge of the lifting operation.


Wayne Miller – Field Crew Foreman

Wayne Miller has been part of the team at Crane-Tec since the mid 1990’s.  He has successfully installed over a thousand cranes ranging from 0.5 to 100 tons.  Wayne’s ability to work as a team player and trouble shoot in the field makes him a true asset to the company. In addition, Wayne Miller is a full time employee who’s primary focus is installing cranes. This sets Crane-Tec apart because the company has dedicated employees focused on one primary task.

Justin Bolduc, a Crane-Tec project manager, spent his first year out of high school working in the field with Wayne Miller.  Justin can attest to Wayne’s extreme dedication to his trade and commitment to quality. Justin explains that after fourteen years, Wayne is still installing overhead cranes with the same commitment and attention to detail.



Overhead Crane & Monorail Safety

Part 1: Before you lift the load

The conditions at the operating site for the hoist must correspond to the operating conditions for which the hoist is designed (including indoor/outdoor use, ambient temperature/radiance temperature, wind, dust, splashing, snow, water, handling hazardous materials, fire risk, etc).  Check that there is adequate lighting at the operating site for operating the hoist safely and efficiently.  If the control position is located on the hoist, check that you can exit from the hoist safely in respective of the hoist’s position on the runway.

Be sure  there are adequate service platforms on the hoist and adequate equipment at the operating site for servicing and inspecting the hoist.  Check that the hoist meets the applicable safety requirements. As always, be certain that the hoist meets the applicable operating requirements and ensure that the components, electrical connections and steel structures of the hoist have been inspected and certified as defect- free.  Also determine if the test loading, test drive and commissioning inspection have been properly carried out and that the handover log has been properly completed.

Safety instructions for operating the hoist:

  1. Read all instructions supplied with the hoist. The hoist operator must be familiar with the instructions and follow them.  The hoist operator must be competent for the task, must know all the controls of the hoist and must be able to use them correctly and safely.  The hoist operator must know how to operate the hoist and must be aware of any risk of accident posed by the operating site.  Learn how to operate the hoist in safe conditions before actually starting to work with the hoist. Learn how to control the movements of the hook and load. Use the Hoist Owner’s Manual to familiarize yourself with the hoist and hoist controls.
  2. Familiarize yourself with the signs and warnings marked on the hoist. The direction symbols for hoist motions are the same as the symbols marked on the push button controller.Check the direction symbols in the Hoist Owner Manual.  Learn the hand signals for indicating hoisting motion, trolley traversing and crane travel. The hoist operator should only accept hand signals from a person authorized to give them.  Ensure that there is adequate lighting as well as proper tools and equipment for the working site and that appropriate working procedures are established.
  3. If the hoist is provided with motion locking devices (EG, rail clamps), open the locking devices before using the hoist.  Before switching on the main current, ensure that all controls are in the 0-position.  Connect current to hoist by turning on the safety switches for main current and for control current.
  4. Close the main contractor by pressing the “START” push button.  If the push button incorporates a selection switch, ensure that the selection switch is in the correct position before using the control push buttons.  Check that all safety switches operate.  Check that the breaks operate.  A hoist that operates outdoors or in cold premises which has been out of service for a longer than normal period of time should always be first started to move the hook upwards in order to avoid damage to the roping from freezing of the rope guide.


Spacemaster SX Hoists on Crane-Tec Overhead Cranes

The Spacemaster SX represents a revolutionary new generation of exceptionally reliable electric wire rope hoists, featuring advanced technology and cutting edge performance.

An innovative design that includes a large drum diameter gives Spacemaster SX hoists the lowest headrooms and best wheel loads in the overhead crane industry, while providing near true vertical lift with single reeved hoists, plus exceptional overhead crane hook approaches and heights of lift.  Unique features include low maintenance, sealed brakes; and trolley inverter control.  The standard hoist nameplate will carry a CSA c/us rating as well as NEMA 3R rating for the electric enclosures.

Spacemaster SX hoists are designed to meet and exceed either ASME H3 or ASME H4 duty ratings and provide the ultimate in easy load handling and overhead crane handling.

Standard configurations for overhead cranes include normal headroom, low headroom and double girder trolley designs.  Hoists in short ton ratings or metric tonne ratings meet a wide variety of application requirements.

Spacemaster Hoists on Crane-Tec Overhead Cranes = Savings in New Construction.

Unmatched Clearances – The floor area under your new overhead crane can now be used more efficiently.  Better hook to wall dimensions compared to the competition.

Lower roof heights/maximum lifting heights – Your new building design can be smaller and more functional giving you saving in initial construction.  Better hook to ceiling dimension.

Lower operating costs – Continual savings in heating and/or air conditioning expenses over the lifetime of your building.

Maximum flexibility – Factory layout and material flow planning is optimized.


Case Study

The Challenge:

  • To provide our customer, a major construction equipment dealer, with a building supported overhead crane system for a new facility in Kentucky. The job incorporated two 10 ton single girder overhead cranes.

Special Consideration:

  • The general contractor needed design build capabilities for the overhead crane and runway systems. Single girder overhead cranes with low headroom hoists were utilized to minimize overhead crane and building steel costs.


  • The general contractor maximized the strength of the building while Crane-Tec supplied a complete overhead crane system and the owner maximized floor space. The overhead cranes were weight tested and turned over to the customer ahead of schedule.

For Immediate Results
Call 800-755-6378


Overhead Crane

Overhead crane

Overhead Crane


Overhead Crane Case Study

The Challenge:

  • To provide our customer, a leading trucking accessories supplier, with a complete design build of an under running 5 ton overhead crane system. The job incorporated the 5 ton overhead crane system and (2) ½ ton jib cranes.

Special Considerations:

  • The general contractor needed design build capabilities for the overhead crane and runway system. Crane-Tec provided complete design of the under hung runway system and incorporated it into the general contractors special overhead crane truss system.

Our Team Approach:

  • Our engineers, armed with building drawings, determined runway steel and hanger design. Engineered drawings with overhead crane loads were submitted to the general contractor for approval. Crane-Tec’s experienced field crew installed the complete system and jib cranes in under 3 days to meet the G.C.’s demanding schedule.


  • The general contractor maximized the strength of the building while Crane-Tec supplied a turn key overhead crane system and the owner maximized floor space. The overhead cranes were ahead of schedule allowing the owner to set up manufacturing machinery with the use of the overhead crane.


Case Study

The Challenge:

  • To provide our customer, a leading forklift manufacturer, with a complete under running 12 ton overhead crane system. The job incorporated the 12 ton runway system and four under running overhead cranes.

Special Considerations:

  • The customer needed design build capabilities for the overhead crane and runway system. Crane-Tec provided complete design of the under hung runway system and incorporated it into the customers metal building.

Our Team Approach:

  • Our engineers, armed with building drawings, determined runway steel and hanger design. Engineered drawings with loads were submitted for approval. Crane-Tec’s experienced field crew installed the complete system and overhead cranes in under 4 days, allowing the customer to use the equipment in the installation of new machinery.


Job History: 5 Ton Crane Syetem

5 Ton Overhead Crane

The Challenge:

  • To provide our customer, a major wire manufacturer, with multiple free-standing overhead crane systems for a new manufacturing facility. The job incorporated a 5 ton capacity free-standing runway system and (2) 5 ton top running double girder tie-back runway systems.

Special Consideration:

  • The general contractor needed design build capabilities for the overhead crane and runway systems. Existing building height limitations requires use of both single girder and double girder overhead crane systems, both with custom low headroom hoists.

Our TEAM Approach:

  • Our engineers, armed with the metal building drawings, determined runway steel locations and sizes. Engineered drawings with loads were submitted to the general contractor for approval.

For Immediate Results
Call 800-755-6378


Insulated Safety Bar

Over the last few years, many new insulated type safety electrification systems have been developed. All of these systems provide a safe means for bringing power to hoists and bridge cranes.

  • The Enclosed Duct Type:  Has two or more conductors inside a square metal track, or individual insulated bars of galvanized steel, copper, or aluminum. These bars are completely enclosed with an insulated shield which has a split on the front edge. A set of collector shoes on the passing crane or hoist equipment bears firmly against the electrification bar and virtually opens the insulated jacket which springs closed again as the equipment passes. This type of electrification can be used for straight or curved requirements.

To accommodate for icing and extreme climate problems, sheet metal covers can be placed over the bars for weather protection and high temperature jackets are available in most situations. The duct type systems are considerably more expensive, utilizing a multiple collector trolley riding inside the square duct. It is a sturdier system and generally offers good weather protection for outside installations. By far the most popular style of insulated system used by crane manufacturers is the individual insulated bar.



Festooning (looped wire) cable systems are simple and inexpensive types of available electrification and offer a relatively trouble free method of bringing electric power to moving equipment. Typically, the only problem with festooning is that the hanging loops could tangle with obstructions or interfere with lifts if installed in areas with low ceilings. Modern festooning systems are normally designed so these possible trouble areas can be eliminated. Festooning systems are an exceptionally valuable system when extensive electrification is required to accommodate numerous push button stations in a pendant control suspended from the crane hoist.

The systems are also extremely effective in high moisture areas or where chemical fumes are present. Festooning may be the only type of electrification that can be used for these applications.  Festoon systems are not recommended for long runways and are generally used for travel lengths limited to 60 feet. Also, festooning wire suspended from a small track and trolley system can be extended for usage up to 150 feet.


Bare Wire Electrification

The most popular system presently on older bridge cranes is bare, hard drawn, copper wire although it is rarely provided today on new equipment. Local electrician codes prohibit their use except under specific conditions.  These systems are installed by a number of hard drawn solid copper or aluminum wires being stretched along the sides of the crane track or under the roof beams and held in place by insulated hangars. This system can only be insulated on straight runs.

For special applications where it is possible to isolate equipment and personnel from electrical lines or when extreme temperatures prevent the use of insulated types of electrification, bare wire can offer an excellent means of bringing power to the equipment.  These bare wires do present a very dangerous safety hazard for service personnel working on equipment or where metal bars, ladders, scaffolding  or other obstructions may come in contact with the lines.


Different Kinds of Electricification

Cord Reels are a very popular method of electrification systems for the smaller capacity hoists and cranes. They offer an inexpensive method of bringing power to moving equipment and most models permit installation in the center of the track to double the effective length of the cord reel cable travel.  Special reels are available for extreme lengths up to 500 feet or more and may be the only type of electrification for outside installation of Gantry cranes where standard overhead electrification systems have no method of support.

Large capacity reels with high amperage ratings, long lengths, or reels with many collector rings may be as expensive as more efficient conventional insulated conductor bar systems. Larger systems should be closely evaluated before choosing this type of electrification.  Contrary to popular usage, cord reels may not be desirable for light weight electric hoists mounted on push type trolleys. The spring tension of the reel can pull the hoist back, even with light loads. Moving the hoist on the track can also be a struggle against the pull of the reel, particularly when the cable is near its extended length.


Monorail Systems

Monorail systems allow exceptional versatility for in-plant handling from simple straight beams to complex curved and interlocking track configurations that can connect many shop and manufacturing areas together. The more complex systems are available with literally hundreds of options and require a study of your plant to best determine a design which will obtain optimum productivity in your application.

I-Beam System:

I-Beam systems are quite practical and relatively inexpensive for low production and simple plant layouts. Often a simple monorail beam will meet your lifting needs without going into the cost of a full area coverage crane system.

I-Beam systems are normally not used for curved and interlocking track applications. The primary advantage of an I-Beam versus Patent Track is the initial cost.

In high usage areas, the soft metal of the I-Beam lower flange will “peen-over” from the highly concentrated trolley wheel loads, resulting in difficulty in moving the trolley and eventually require replacement of the trolley and tracks.

Patent Track System:

Patent Track on the other hand, has precision hardened and ground flanges. Trolley wheels are individually suspended on articulating trunnions which assure equal wheel loading and provide much less effort to move heavy loads. These systems are ideally suited for high production applications. They are also suited ideally for integrated installations which require a crane mounted hoist for full area coverage to align with an interlocking monorail beam and deliver parts to remote assembly or storage areas.

It is possible with a monorail system to move loads down halls, around corners, up inclines, and even vertically lift entire hoist, load, and rail section between floor levels.
To obtain maximum usage of your plant potential, monorails should be seriously evaluated to interface with crane and fork lift operations.

For questions concerning monorails, contact Crane-Tec or call us at 800-755-6378.


Crane Design

Very few machines exist in as wide a variety of designs as cranes. Before the crane is constructed, the manufacturer must consider the site where it will be used and the weight it will need to lift. In addition, cranes are often modified to suit the needs of the user. For this reason, it is not much of an exaggeration to say that no two cranes are exactly alike.

Cranes used for industrial purposes are generally designed to remain permanently in one location. These cranes often perform repetitive tasks that can be automated. An important type of industrial crane is the bridge crane. Traveling on tracks attached to two horizontal beams, known as a bridge, a trolley enables the movement of the bridge crane. Usually, the bridge itself can be moved along a pair of parallel rails, allowing the crane to reach a large, rectangular area. A bridge crane may also be designed so that one end of the bridge is supported by a central pivot while the other end moves on a circular rail, allowing a large, round area to be reached. An overhead traveling crane is a kind of bridge crane in which the rails are located high above the ground. Usually supported from the ceiling of a building, an overhead traveling crane has the advantage of causing no obstruction in the work area.

Cranes used in construction often perform a variety of tasks and must be controlled by highly skilled operators. Construction cranes are divided into mobile cranes and tower cranes:

Mobile cranes:

  •  Mounted on trucks or crawlers in order to travel from place to place. An articulating crane is a mobile crane in which there is a joint between two sections of the boom, allowing it to move in a way similar to a knuckle in a human finger. Articulating cranes are generally used to lift objects located a relatively short distance away, but with a wide range of motion. A telescoping crane is a mobile crane in which two or more sections of the boom can extend and retract, changing the length of the boom. Telescoping cranes are less versatile than articulating cranes, but are usually able to lift heavier objects located a greater distance away.

Tower Cranes:

  •  Used in the construction of tall buildings. They are installed when construction begins and dismantled when the building is completed. An external tower crane is installed outside the building. As the building increases in height, the crane is raised by lifting the upper part of the crane and adding a new section of tower beneath it. An internal tower crane is installed within the building. As the building increases in height, the crane is raised by lifting the base of the crane to a higher level within the building..



Crane Background

A crane is a machine that is capable of raising and lowering heavy objects and moving them horizontally. Cranes are distinguished from hoists, which can lift objects but that cannot move them sideways. Cranes are also distinguished from conveyors that lift and move bulk materials, such as grain and coal, in a continuous process. The word crane is taken from the fact that these machines have a shape similar to that of the tall, long-necked bird of the same name.


Human beings have used a wide variety of devices to lift heavy objects since ancient times. One of the earliest versions of the crane to be developed was the shaduf, first used to move water in Egypt about four thousand years ago. The shaduf consists of a long, pivoting beam balanced on a vertical support. A heavy weight is attached to one end of the beam and a bucket to the other. The user pulls the bucket down to the water supply, fills it, and then allows the weight to pull the bucket up. The beam is then rotated to the desired position and the bucket is emptied. The shaduf is still used in rural areas of Egypt and India.
As early as the first century, cranes were built that were powered by human beings or animals operating a treadmill or large wheel. These early cranes consisted of a long wooden beam, known as a boom, connected to a rotating base. The wheel or treadmill powered a drum, around which a rope was wound. The rope was connected to a pulley at the top of the boom and to a hook that lifted the weight.
An important development in crane design occurred during the middle Ages, when a horizontal arm known as a jib was added to the boom. The jib was attached to the boom in a way which allowed it to pivot, allowing for an increased range of motion. By the sixteenth century, cranes were built with two treadmills, one on each side of a rotating housing containing the boom.
Cranes continued to rely on human or animal power until the middle of the nineteenth century, when steam engines were developed. By the end of the nineteenth century, internal combustion engines and electric motors were used to power cranes. By this time, steel rather than wood was used to build most cranes.
During the first half of the twentieth century, European and American cranes developed in different ways. In Europe, where most cranes were used in cities with narrow streets, cranes tended to be built in the form of tall, slender towers, with the boom and the operator on top of the tower. Because quiet operation was important in crowded cities, these tower cranes were usually powered by electric motors when they became widely available.
In the United States, cranes were often used in locations far away from residential areas. Cranes tended to be built with the boom connected to a trolley, which could be moved easily from place to place. These mobile cranes tended to be powered by internal combustion engines. During the 1950s, the availability of stronger steels, combined with an increased demand for taller buildings, led to the development of cranes with very long booms attached to small trucks, or to crawlers with caterpillar treads. Mobile cranes and tower cranes of many different kinds are used extensively in construction sites around the world.


The Purpose of Overhead Cranes

Overhead bridge cranes are some of the most versatile and widely employed types of cranes on the market. They can be found in warehouses and manufacturing facilities across the country.


The function of an overhead bridge crane is to lift a workload, removing it from one location and depositing it in another location. To perform a lift with an overhead bridge crane, a workload is rigged to the crane’s hook. A cable raises and lowers the hook. The cable is attached to a trolley, which travels side by side along the crane’s bridge. The bridge can travel along two runways to deposit a work piece to another location.


Only people who have been certified by OSHA (Occupational Safety and Health Administration) are qualified to operate overhead bridge cranes in America. Overhead bridge crane certification facilities are located throughout the country. For example, in Atlanta, Georgia, consumers can find OSHA training courses at Georgia Tech Institute.

Safety Measures

An overhead bridge crane must pass regular safety inspections (performed by OSHA-certified inspectors) before it can be used to lift a work piece. Overhead bridge crane operators should be careful to never lift a work piece that weighs more than the crane’s maximum load limit. Load limits are usually clearly marked on the sides of the crane, where they would be clearly visible to the crane operator at all times.