Lifting magnets have been around for many decades. Over time, the effectiveness and operational capacity of rare earth materials have allowed the advancement of much stronger and durable magnetic lifting systems. However, the powerful construction of these massive devices makes it more hazardous on the construction site.
Operators and managers go through rigorous training and safety protocols to ensure they operate machines safely. But even a minor lapse in the operating procedure can lead to injuries and fatalities. In this vein, the American Society of Mechanical Engineers (ASME) continues to devise new and improved safety guidelines for lifting magnet operations.
Electric-rated and permanent lifting magnets should comply with the safety standards established by ASME B.30.20-3. The scope of this section is to address the installation, marking, construction, maintenance, operation, and testing of close-proximity lifting magnets.
The ASME B.30.20-3 addresses the lifting magnet operator’s concern regarding manual positioning and guidance. It also expands on the safety precautions used when the machine is operated in close proximity to people.
Since lifting magnets can lead to a number of injuries from crushed fingers to loss of limbs, operators are required to follow the ASME compliance guidelines and ensure worker safety.
Lifting Magnet General Safety Guidelines
Some safety guidelines that lifting magnet operators are required to comply with include:
- Go through all instructions before operating any lifting magnets.
- Be aware of the magnet capacity for material thickness being lifted.
- Remove the magnet from service if safety first tags are missing.
- Follow precautions while handling the magnets near metallic elements.
It’s crucial that the magnets are placed in an area away from pipes, carbon steel chutes, charts, I-beams, and other magnets. If caution isn’t exercised around them, workers’ safety can be put in danger. In a matter of seconds, chaos can ensue, leading to severe injuries.
Hence, the ASME emphasizes using “strong magnet” labels where magnets are being lifted and handled. They should also already have warning labels attached when they arrive from the manufacturer.
No worker or personnel should stand directly under the path of the magnet. People should be asked to clear the path underneath the lifting magnets before moving them. While shifting electromagnets, operators should be warier as a split-second of power loss can disable the magnet and lead to irreparable losses.
An oily magnet surface is another common reason for drops. It may attract debris that can ruin the attraction between the magnet and the item being lifted. Hence, it’s best to assume a safe distance to ensure no one gets hurt due to the sudden slip.
Factors Affecting Lifting Magnet Operation
The ASME B.30.20-3 does an excellent job of addressing safety concerns during lifting magnet operations. Some of these include:
Composition: The material being lifted should be made of steel. If you use alloys or any other elements, they may not be as effective as low-carbon steel.
Surface: Make sure the material is clean and free of oil traces. Dust, debris, rust, ice, snow and other elements can weaken the pulling force and cause air gaps. It’s crucial that the full surface of the magnet is in contact with the material.
Configuration: Full safety of the magnet can be ensured when the material is flat without any waves or bows. Make sure that the there’s no dunnage between the articles that weaken harm the connection.
Weight: Weigh the article before using the lifting magnet to move it. Steel can be weighed using this formula: Length (in.) x Width (in.) x Thickness (in.) x 0.283 lb. /in.3.
Temperature: Temperature is one of the most crucial factors in ensuring lifting magnets’ safety. However, this element can also be the most ignored. While ceramic permanent lifting magnets should be lifted at a maximum material temperature of 200 degrees F, electromagnets require an optimal temperature of 600 degrees F.
If you don’t want your lifting magnet to lose strength, make sure they aren’t subjected to high-temperature environments or high electric fields. Avoid damages and ensure they are spot-free.
Thickness: Keep in mind that thicker objects are easier to lift than thinner objects. Since thinner objects can’t accept all lines of force, they may experience reduced capacity.
Additional considerations of lifting magnets
Magnets are harmful to magnetic storage devices such as hard drives, flash drives, and other computer parts. Hence, make sure that they are never placed in close proximity to an electronic device. Even mobile phones should be kept miles away from lifting magnets.
Medical devices are also prone to damage if placed near lifting magnets. People will medical devices should stay away from these heavy-duty devices.
About the Author
Mark is a civil engineer and crane safety expert. He has been working in the crane safety and management industry for over ten years. He currently serves as a senior consultant at Crane Warning Systems Atlanta, a leading crane load monitoring system’ distributor in the US.
In his free time, the author surfs on the beach and writes informational blogs on construction equipment safety. Visit his company’s website to learn more about their operations.