There are plenty of things that can derail progress at a jobsite, not the least of which is equipment that is down. Sometimes the repairs require the use of a service truck with a crane, for example, to lift and remove an engine or other heavy component that has failed on site.
While truck cranes are designed to tackle the heavy lifting, it’s important to prepare for a safe lift — one that avoids damage to equipment and injuries to workers.
Before a lift even occurs, Nathan Schiermeyer, director of engineering, Maintainer, highlights the importance of utilizing trained and competent operators to perform the lift. “Crane operators need to be competent individuals as defined by OSHA,” he says. “A competent operator requires training and familiarization with the specific equipment to be used. The operator also needs to know all applicable federal and local regulations and requirements.”
Tom Wallace, sales manager, Iowa Mold Tooling (IMT), emphasizes an additional critical pre-lift item: conducting a crane inspection. “Conduct a thorough visual checkup by walking around the entire crane during daily inspections and again before doing a lift,” he advises. “Operators need to ensure that all the parts of the crane have been checked and are in good working condition before any lifts.”
Inspect the crane for leaks, including looking for hoses that might have a defect that could become a leak. Also check the wire rope on the winch for any frays or nicks that could pose a potential problem, and look for hazards caused by defects in the equipment due to wear and tear or damage that might have occurred.
“By identifying these issues before a lift, you can prevent more damage from occurring and avoid accidents,” says Wallace. For new operators, or seasoned operators with questions or concerns, IMT provides a manual with each crane model that outlines a daily inspection checklist for the crane body and chassis. “Using that checklist, you can ensure you’re inspecting every piece of the equipment.”
Tim Davison, product manager, and Matt Schroeder, engineering manager, Stellar Industries, point out that more companies are requiring operators to conduct a lift (“pick”) plan. It includes a review of the ground conditions and surrounding environment, load/weight calculations and verifications and other items.
“It’s about safety,” says Davison. “And it’s about planning before you act,” adds Schroeder.
Identify Site Hazards
Lift evaluations at the jobsite should start at ground level. “Whenever possible, the stabilizers should be on level, stable ground,” Wallace recommends. “Be aware of ground conditions before deploying the stabilizers so you can avoid situations like the stabilizers sinking into mud.”
Davison agrees, adding, “If a stabilizer leg isn’t on firm ground, you can tip the truck. Make sure the truck crane is on solid footing, rather than on a newly excavated piece of ground that is soft.”
Cribbing or an outrigger pad can be used to provide additional support, if needed. “You want to increase the surface area,” says Davison. For example, wood placed in a waffle- or lattice-type pattern can spread the weight of the crane over a much larger area, thereby giving it added flotation. “It’s similar to tossing a piece of steel into a body of water. It will sink because it doesn’t displace enough water for it to float. Conversely, an aircraft carrier has a lot of surface area that displaces the water and spreads out the load so the ship can float. It’s all about surface area and displacing weight. It’s the same way with the ground. If it isn’t terra firma, or firm ground, you need to find a way to spread out the weight.”
Wallace concurs, adding, “If there is any doubt of the ground conditions, an expert in rigging or site surveyor should be utilized.”
Once ground conditions are assessed, attention should be directed to the rest of the working area, including identifying any potential hazards and obstructions within the perimeter. “The area needs to be clear,” says Schroeder. “Check for other equipment and be sure to look overhead for any power lines and maintain a safe distance from them.”
Schiermeyer also stresses the importance of checking for other workers who may be in the area. “Personnel are not allowed to be in the fall zone of the crane,” he says. “Frequently with service trucks, this step is overlooked as there are often other people working on the same equipment being repaired. A competent crane operator will never place himself between the load being moved and another object.”
With the environment secured, operators can turn their attention to lifting the load, taking into consideration its weight, as well as the position of the crane on the vehicle and the position of the load in relation to the crane — both of which can affect maximum lifting capacities.
“As operators prepare to lift the load after inspecting the crane, they need to fully understand how much that load weighs,” says Wallace. “Knowing what your load weighs is essential to any lift that’s going to be done safely to prevent potential hazards. Often, operators just guess, but that is not sufficient. They need to know the actual weight to avoid overloading the crane.”
To ensure the crane operates within safe load limits, refer to the load charts that are published in the owner’s manual. In the case of some manufacturers, load charts can also be found on the machine itself. With IMT cranes, they can be found both on the crane and on the door of the crane compartment. The charts indicate maximum lifting capabilities as well as how the position of the crane affects lifting capabilities.
“When the crane is on the back corner of the body, as with most mechanics trucks, the most stable lifting zone is off the rear of the truck,” says Schiermeyer. “The owner’s manual of any crane/body will give the specifics of the unit being used. The operator must make sure that the load to be lifted falls within the crane capacity chart, and also the stability zone of the vehicle.”
As you rotate the crane, that load chart will indicate the maximum load limit in each particular quadrant, adds Wallace. “Be aware of where those load limits are and the angle of your crane,” he says. “IMT offers a 360° stable crane environment on many models, so you will remain stable if you follow the chart all the way around the truck.
“Recently, the marketplace has been trending toward trucks without front stabilizers due to their impact on overall weight. What that means, however, is the cranes on these trucks... become derated,” he points out. “If an operator is in a truck without a front stabilizer, they need to be aware that as they move the crane, the load may become derated. For example, if the load is 100% stable directly behind the truck, as you move it toward the cab, it might drop to 60%. So the operator needs to realize that the crane can only lift 60% of what it’s rated at in that quadrant.”
Davison and Schroeder also indicate that the position of the load in relation to the crane can affect how much can be lifted.
“The farther away the load is from the crane, the less weight the crane can pick up,” says Davison. “It’s no different than if you were to pick up a box off the ground. When you reach down to pick it up at your feet, you can lift more than if you are forced to reach for it over a chair and 3 ft. away from you.”
Safe Lifting Techniques
It’s always a good idea to conduct another quick visual inspection prior to a lift, advises Wallace, noting that it’s important to double check for power lines or obstructions and, most importantly, verify that no one is around who could be caught in the way of the lift.
“Make sure the stabilizers are completely deployed,” he continues. “It’s also always good to check the rigging. Make sure all safety devices are in place so the load doesn’t slip off the hook. Remember that safety devices and load charts are not suggestions. They are mandatory rules to follow.”
Davison also recommends that loads be kept as low to the ground as possible during the lift. “People may want to bring a load into the air,” he comments. “But you never need to bring it farther off the ground than it needs to be. For example, if you are picking an engine from a piece of equipment, once you have cleared the machine, bring it down closer to the ground. I recommend bringing it to within a foot of the ground. Until you need to raise it into the back of the service truck, there is no reason to have it high in the air. It may be faster to keep it raised throughout the lift, but it isn’t as safe.”
Once the lift is complete, it’s important to secure the load and properly stow the crane, stabilizers, winches and any moving components, says Schroeder.
Built-in Safety and Control Features
To help ensure safety and prevent overloading situations, as well as to maximize control and stability throughout a lift, manufacturers have built several features into their machines.
“The overload systems on the cranes on the market today are much more sophisticated than they used to be,” says Wallace. “They keep the lift stable, which in turn keeps the operator and the equipment safe. Overload systems make sure the operator and the equipment leave at the end of the day in the same condition in which they started.”
IMT also includes LED lights on its radio remote handsets, which tell operators how much of the total load is being used. “As they’re lifting, the remote handset might say they’re at 60% of load, which will indicate to the operator that they may need to relocate for a different lifting approach in order to maximize the lift safely,” Wallace explains. He notes that while the company recently added LED lights to single-proportional remotes, they have always been available on the fully proportional remotes.
Another new feature on IMT cranes is boom tip lights. “Boom tip lights are incredibly useful for working in dark conditions, and are a huge safety factor,” says Wallace. “The lights continually adjust to ensure both the load and the work area are lit at all times. This gives operators a continuous line of sight on the load as well as the jobsite to ensure operations can be safely executed.”
Schiermeyer indicates that every Maintainer crane has overload protection via sensing pressure in the lift cylinder. “When the crane is nearing full capacity, the speed is automatically decreased to reduce boom bouncing and excessive swinging of the load,” he says. “When the crane is at maximum capacity (anywhere in the lifting area), the lift up, lift down, hoist up and extend out functions are disabled. Newer technology allows the wireless crane remote system to display (in percentage of total, or cumulative capacity) the load that the crane is lifting.”
Schiermeyer adds that while all properly functioning cranes are designed with overload protection, the operator should never rely only on the overload protection device to limit the lifting capacity. “Before making a lift, the operator needs to take time to plan the lift, making sure that where the load is being picked and where the load is being moved to are both within the reach and capability of the crane/truck,” he emphasizes. “If the load is not in the direct line of sight of the operator, the operator should relocate the truck/crane, or his/her own location.”
Maintainer cranes are also equipped with a proportional remote control. “When the operator is near to the desired location, he/she can ‘feather’ the load accurately into place,” Schiermeyer says. “Additionally, the overall speed of the functions can be adjusted directly on the remote control in increments of 100%, 75%, 50% and 25% so the operator gains even more finite proportional control.”
While wireless remote control systems allow full mobility around the load, Schiermeyer notes that if conditions prohibit radio signal, the operator should employ a signal person who can be in direct line of sight of the load. “A hand signal chart is provided with each unit that we build,” he adds.
To simplify some of the manual calculations required to ensure a safe lift, Stellar Industries offers Crane Dynamics Technology Plus (CDTplus). The hand-held transmitter features an LCD display that provides feedback for the operator, including real-time load capacity, maximum distance with the current load, boom angle and percentage of load.
“It provides an initial check before you ever try to move something,” says Davison. “You can hover it over whatever you want to pick and it will indicate what the crane is capable of lifting before you ever hook up a load.”
It also includes a sensory indicator that alerts the operator when he/she is approaching maximum capacity. “The handle of the remote will vibrate,” says Davison. “The operator can feel that vibration so they know they need to change behavior to reduce the load. We’re trying to communicate to the operator all the time to give them as much information as we can.”
An additional “boost” mode allows a momentary increase in the capacity of the crane. “If you are within 18% of the initial load capacity, you can press the boost button,” says Schroeder. “It will slow down the crane and give you another 18% lifting increase.”
Stellar cranes also feature On-Demand Speed Control, which ramps up engine rpm only when the crane is being used. “Running the crane or compressors can create a lot of noise in the work area,” says Davison. “With our system, the engine rpms of the truck only come up when the operator actively hits a function on the crane. The engine rpms return to idle when the crane or compressors aren’t being used. The benefit is that when you aren’t using the crane, you don’t have the noise of the truck engine. It makes for a safer work environment because you can hear other things that are going on around you.”