1. load verification of slings and riggings
The newly purchased slings and riggings shall not be put into use until they have passed the test according to the specified test load and test method on the basis of no-load operation and qualified test.
Static load test
● 1.25 times the rated lifting capacity of the lifting appliance
● the sling shall be 2 times of the limit working load of a single branch.
● test method: gradually increase the test load and lift it to 100-200 mm above the ground. The suspension time shall not be less than 10 minutes. Repeat the test three times for visual inspection.
Judgment: if there is no crack or permanent deformation in the structure, and there is no abnormal loosening or damage at the connection, the static load test is qualified.
Dynamic load test
● 1.1 times the rated lifting capacity of the lifting appliance
● the sling shall be 1.25 times of the limit working load of a single branch.
● test method:
During the test, the acceleration, deceleration and speed must be limited within the normal working range of the crane and rigging, and the actual continuous operation shall be 1 hour,
Judgment: if the structural components are not damaged and all parameters meet the requirements of technical performance indicators, the dynamic load test is qualified.
2. safe use of slings and riggings
(1) Slings and riggings shall be suitable for the type, environmental conditions and specific requirements of the lifted articles.
(2) Before operation, the slings and riggings shall be checked to confirm that all functions are normal and intact before being put into use.
(3) Before hanging, confirm whether the lifting and hanging joints set on the heavy objects are firm and reliable: before lifting, confirm whether the binding and hanging are reliable
(4) The lifting appliance shall not exceed the rated lifting capacity, and the sling shall not exceed its large safe working load.
(5) During the operation, the lifting objects, slings and riggings shall not be damaged. If necessary, protective pads shall be added between the lifting objects, slings and riggings
Rope is an indispensable tool for binding and fixing objects in the process of lifting, and it is also the main flexible component of the sling
Note: the difference between flexible parts and rigid parts: flexible parts are allowed to have a certain amount of bending deformation, while rigid parts are strictly prohibited from bending deformation. The vast majority of mechanical applications are rigid parts, which require good rigidity