Scrap standards for commonly used slings

Scrap standards for commonly used slings

1. Sling scrap standards

When one of the following conditions occurs to the sling, it should be scrapped:

(1) The webbing (including protective cover) is severely worn, perforated, cut, and torn;

(2) The load-bearing seams bloom and the sutures are worn out;

(3) The sling fibers soften, age, become less elastic, and weaken in strength;

(4) The fiber surface is rough and easy to peel off;

(5) The sling has a dead knot;

(6) The surface of the sling has excessive loose spots, corrosion, burns, thermal melting or scorching;

(7) The cordon with the red cordon sling is exposed.

2. Fiber ropes and hemp ropes used for hanging objects

Those that meet one of the following conditions should be updated and scrapped:

(1) The rope is cut, broken, severely worn, and the rope strands are loose or partially broken;

(2) The fibers on the surface of the rope are severely worn, the local rope diameter becomes thinner, or the wear of any strand exceeds 30% of the original diameter;

(3) Severely bent or twisted;

(4) The rope becomes moldy and deteriorates, burned by acid and alkali, melted or scorched by heat;

(5) The plug joint is damaged, the rope strand is pulled out, and the eyelet is damaged;

(6) Scrapped ropes shall not be repaired and reused.

3. Wire rope scrap standards

When one of the following conditions occurs in the wire rope, it should be scrapped:

(1) Irregularly distributed damage: within a length range of 6 times the diameter of the wire rope, the total number of broken wires can be seen to exceed 5% of the total number of wires in the wire rope;

(2) The wire rope is partially damaged by broken wires, and more than three broken wires are gathered together;

(3) Breakage, extrusion, and distortion of the entire strand of the wire rope;

(4) The core of the wire rope is extruded;

(5) The wire rope is severely worn: the diameter of the wire rope is measured at any position and the size is less than 90% of the original nominal diameter;

(6) The wire rope is severely corroded: the flexibility is reduced and the surface is obviously rough. The actual diameter of the wire rope measured at the rusted area is less than 93% of the original nominal diameter;

(7) The wire rope is distorted, crushed, or core damaged due to knotting, twisting, or extrusion, or the wire rope is flattened by more than 20% of the original nominal diameter;

(8) The plug-in joint is severely squeezed and worn; the metal casing is damaged (such as cracks, severe deformation, corrosion) or the diameter is reduced to 95% of the original nominal diameter;

(9) There are concentrated broken wires on the surface of the grommet or the broken wires are concentrated near the metal casing, the plug-in joint, and the plug-in connection rope strand;

(10) Thermal damage of steel wire rope; strength reduction caused by arc, immersion in molten metal or long-term exposure to high temperature environment.

4. Scraping standards for hanging chains

When one of the following conditions occurs to the hanging chain, it should be scrapped:

(1) The link undergoes plastic deformation and elongates by 5% of the original length;

(2) The wear of the contact parts between the chain rings and the connection between the chain rings and the end fittings is reduced to 80% of the original nominal diameter; the wear of other parts is reduced to 90% of the original nominal diameter;

(3) Deep dents and sharp transverse dents in cracks or high tensile stress areas;

(4) After the link is repaired, the transition fails to be smooth, or the diameter decreases by more than 10% of the original nominal diameter;

(5) Distortion, severe corrosion and scale accumulation cannot be eliminated;

(6) The dangerous section wear of end fittings is reduced by 10% of the original size;

(7) When cracks, bending or twisting occur in any part of the hanging chain, or when there is jamming or stiffness between the hinges, which cannot be ruled out.

5. Hook scrap standards

When one of the following conditions occurs to the hook, it should be scrapped:

(1) Cracks and cracks appear on the surface of the hook;

(2) The wear or corrosion of the dangerous section reaches 10% of the original size;

(3) The opening is increased by 15% compared to the original size;

(4) The twisting deformation of the hook body exceeds 10 degrees;

(5) Plastic deformation occurs in the dangerous section of the hook or the hook neck;

(6) The hook thread is corroded;

(7) When the plate hook bushing is worn to 50% of its original size, the bushing should be scrapped;

(8) When the plate hook spindle wear reaches 5% of the original size, the spindle should be scrapped.

6. Shackle scrapping standards

When one of the following conditions occurs to the shackle, it should be scrapped:

(1) The shackle has obvious permanent deformation and the horizontal pin can no longer rotate freely;

(2) The cross-sectional wear of any part of the body and cross pin exceeds 10% of the nominal size;

(3) The torsional deformation of the shackle exceeds 10%;

(4) Cracks occur in any part of the shackle;

(5) The shackle cannot be locked.