The Wikipedia definition of SWL is:
Safe Working Load (SWL) sometimes stated as the Normal Working Load (NWL) is the mass or force that a piece of lifting equipment, lifting device or accessory can safely use to lift, suspend, or lower a mass without fear of breaking.
“Safe workload” is also synonymous with “normal workload”. According to irata.org, “safe workload” is defined as “breaking load of a component divided by an appropriate safety factor that provides a safe load that can be lifted or transported.” Safe workload is the mass of cargo (cargo) that the lifting machine such as a crane can transport without fear of breaking.
Now, who sets the lifting capacity for a specific lifting equipment?
It is a manufacturer of lifting equipment. The manufacturer recommends the maximum load capacity of its lifting equipment. Lifting equipment or machine may be a crane, rope, line, hooks, brackets, slings or any lifting device. To know the safe workload, the minimum tensile strength of elevator equipment is divided by a safety factor that is constant or tied to a particular type of equipment. Typically, the safety factor of a particular equipment ranges from 4 to 6. If the equipment poses a risk to human life, the safety factor increases to 10.
Since the definition of “safe workload” is not very specific and has legal implications, US standards have begun to stop using the term. A few years after US standards began to stop using the term, European and ISO standards began to follow suit. Later, both Americans and Europeans developed a more suitable term and definition of the maximum lifting capacity of a particular lifting device. Both parties agreed to use the term “workload limit” or WLL.
Based again on the file provided at itera.org, a specific definition of the workload limit is that it is the maximum mass or force that the product has the right to support in the common service when gravity is applied in a line, unless otherwise specified, relative to the centerline of the product. This definition can also be added to the following definitions: the maximum load that an element can lift; and the maximum load that an element can lift in a particular configuration or application.
The workload limit of lifting equipment is highly dependent on a competent and qualified manufacturer who skillfully determines its WLL value. The manufacturer must determine the correct or approximate WLL value for each lifting machinery. To come up with the meaning of WLL, there are many factors to consider. This includes the speed of work, the applied load, the length of each rope or line, the size, number, etc. You should carefully monitor any factor that may affect the limits of the working load of the lifting machine.
- WLL stands for workload limitation, while SWL stands for safe workload.
- WLL and SWL are terms often used in the technical field.
- Safe workload is the longest term for limiting workload.
- The definition of safe workload is the breaking load of a component divided by the appropriate safety factor that provides a safe load that can be lifted or transferred.
- The workload limit is that the maximum mass or force that the product has the right to support in general maintenance when the thrust is applied in accordance, unless otherwise specified, with respect to the center line of the product.