Definitions

Definitions
Static Load — The load resulting from a constantly applied force or load.
Working Load Limit — The maximum mass or force which the product is authorized to support in general service when the pull is applied in-line, unless noted otherwise, with respect to the center line of the product. This term is used interchangeably with the following terms.
1. WLL
2. Rated Load Value
3. SWL
4. Safe Working Load
5. Resultant Safe Working Load

Working Load — The maximum mass or force whichthe product is authorized to support in a particular
service.
Proof Load — The average force applied in the performance of a proof test; the average force to which a product may be subjected before deformation occurs.
Proof Test — A test applied to a product solely to determine non conforming material or manufacturing defects.
Ultimate Load — The average load or force at which the product fails, or no longer supports the load.
Shock Load — A force that results from the rapid application of a force (such as impacting and/or jerking) or rapid movement of a static load. A shock load significantly adds to the static load.
Design (Safety) Factor — An industry term denoting a product’s theoretical reserve capability; usually
computed by dividing the catalog Ultimate Load by the Working Load Limit. Generally expressed for blocks as a ratio of 4 to 1.
Tackle Block — An assembly consisting of a sheave(s), side plates, and generally an end fitting (hook, shackle, etc.) that is used for lifting, lowering, or applying tension.