• Examine the load hook and where necessary use the dye penetrant test method. • If the load hook has any of the following signs of cracks or excessive wear, remove the hook from service: •The throat opening measured at the narrowest point has increased by more than 15% of the original opening. •The hook has twisted more than 10 degrees from the original plane of the hook. •Wear in excess of 5% in the neck of the hook and 10% in other areas including the bow of the hook. •The hook has nicks, wear, gouges, deformation damage or cracks to
the hook and exceeds any criteria specified by the manufacturer’s standard or local legislation. This includes non-OEM gouges placed on hooks to measure throat openings. Exposure to excessive temperatures will damage the heat treatment and material strength, severe weld splatter and arc strikes to the load hook can create stress concentration. •Additionally, on Block or Ball Hooks. Elongated ball pin holes hook latch pin holes and swivel eyes exceeding 5% of the original diameter.
•Swivel end play gap exceeding 2mm. Excessive endplay may indicate damaged to internal set screw Check the hook latches work correctly, ensure that the latch bridges the throat of the hook when
in the automatic closed position and that it activates correctly. If the crane load hook is being used for the purpose of lifting personnel in a man basket the hook shall have a positive locking latch device fitted. All hook blocks shall have identification plates with the following information. Manufacturers name, serial number, hook lifting capacity and weight of the hook assembly. Before reassembling of the load hook, make sure the bearing is greased as required and the hook/ nut threads are coated with a commercial sealant to provide a corrosion resistant surface. During reassembly check that the length of the threads engaged between the hook and nut is at least equal to the hook thread diameter. Also check that the nut retaining pin, set screw, or key which prevents the nut from backing off the hook is in place and secured. Finally, the load hook and assembly block shall be tested annually by a Certified Lifting Machine Inspector. Remember that failure to comply with your required responsibilities may result in serious injuries or fatalities.
Contact Richard Haddath, Cranemec Group, Tel: +27 (0) 16 366-1393, Cell: +27 (0) 83 268-4857 info@cranemec.co.za www.cranemec.co.za Lifting Africa - Jan/Feb 2019
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INSPECTION & MAINTENANCE
cracks, wear and any other damage affecting the safe use of the hook assembly.