4.2 Heavy Equipment You May Encounter at the Jobsite
4.2 Heavy Equipment You May Encounter at the Jobsite
Douglas Rupik, M.Ed., JIW
Identifying Heavy Equipment and Their Function
Equipment and machines have enabled us to increase our productivity as well as take on tasks that would otherwise be too big for us as individual welders. Never forget that just as these machines easily accomplish heavy tasks, they can also easily injure or kill you.
Heavy equipment can be categorized as:
- metalworking or metal forming, such as presses, punches, lathes, etc.;
- handling equipment, such as hoists and lifting equipment;
- aerial platforms and other access equipment; and
- earthmoving equipment
Safe Use of Handling Equipment
Cranes, forklifts, and hoists are so commonly seen and used on jobsites that it is easy to become complacent about safety when around them. However, injury and death can result from improper use of these types of equipment. In fact, as a result of accidents over the years, the government has increased training and credential requirements regarding who is allowed to operate and work with these machines, especially cranes, in construction. It is best to form good habits for working around these equipment and then continue with them for the entirety of your career.
Hoisting equipment is used to lift heavy loads from above and move them. Chain falls and cranes are examples of hoisting equipment. Lifting equipment, such as jacks and forklifts, is used to lift materials from below and then move them.
There is a temptation to use forklifts for both hoisting and lifting. But unless a forklift has the appropriate attachments to be used as a hoist, never hang loads below the forks.
Cranes appear deceptively simple to use, with overhead bridge cranes and jib cranes in shops being the easiest to use. However, you still need training to operate them safely. Misplaced confidence in one’s skills plus an overhead crane with a heavy load is an accident waiting to happen.
Before hoisting an object, answer two questions: How much does the object weigh, and where does the object need to be moved? The answers determine what crane and rigging need to be used. Do not allow the need for a job to be done in a hurry force you, and potentially the entire jobsite, into an unsafe situation. If the crane or rigging is not rated for the load, do not use it!
When you are calculating the load that can be applied to a crane, include the known weight of the object to be moved plus the weight of the crane’s hook and any rigging that will be used. If the weight of the object to be lifted is unknown, do not attempt to lift it. Instead, refer to the shipping information, blueprint, or manufacturer to determine its weight before proceeding.
When using a ground crane for hoisting, such as a crawler crane or boom truck, also include in your calculations how much the crane’s capacity is reduced by increased radius—that is, the further the load is moved away from the crane, the less capacity the crane has. To understand this idea,