When there are the following defects, the Lifting Hooks for Cranes should be scrapped and replaced:
(1). Hook surface with crack or break;
(2). Dangerous section erosion rate more than 10% of the original size;
(3). Dangerous section and hook neck part with plastic deformation;
(4). Casting gap increase of 15% compared to the original size;
(5). Tip of the hook torsional deformation of more than 10%;
(6). Board hook bushing wearing capacity reaches 30% of the thickness dimension, the bushing should be scrapped.
(7). Board hook spindle wearing capacity reaches 5% of the original size, mandrel should be scrapped.
