In normal use, all wire ropes will eventually be scrapped due to repeated loading. In many cases, although the oilfield wire rope is used normally and the structure is reasonable, the service life of the oil field wire rope will be greatly shortened by the bad service conditions or incorrect use. The following is the wire rope used in the oilfield failure and its causes. These failures lead to premature rope failure and replacement. It is likely that one or more of the following conditions may cause premature replacement of oil field wire rope during use:
1) fracture of oil field wire rope (all strands broken)
Causes: severe impact during use causes overload, twisting, damage, local wear, damage of one or several strands, serious corrosion or loss of elasticity of the wire rope, which causes the steel wire to break when it is bent in use and reduce the metal sectional area in the wire rope.
2) One or more strands of oil field wire rope are broken
Causes: wire rope overload, twisting, friction with other parts, local wear or severe corrosion, fatigue, overspeed, slipping or over relaxation during operation, so that the vibration is concentrated on the static pulley or dead line anchor.
3) Excessive corrosion:
Cause: the wire rope lacks lubrication. Expose the wire rope to salt spray, corrosive gas, acid water, drilling fluid or dirt. The wire rope lacks adequate protection during storage.
4) when handling the oil field wire rope, the wire rope is damaged due to careless operation
Causes: rolling rope wheel from obstacles, rope wheel falling from truck or platform; chain: directly binding on steel wire rope or directly supporting on steel wire rope with crowbar; nailing steel wire rope on wheel flange with nails.
5) The rope sleeve of oil field wire rope is not suitable and damaged
Causes: improper binding causes one or more strands to rotate in reverse direction, resulting in slack of wire rope; improper way of installing rope sleeve or poor installation process of rope sleeve, wire rope rotates back and forth in rope sleeve or extends out from rope sleeve.
6) Twisting, bending and other distortions of oil field wire rope:
Causes: the method of pulling the steel wire rope from the rope pulley or rope reel is incorrect, the winding on the drum is not correct, and the same determination is incorrect; the wire rope is not placed properly when it is pulled out from the rope pulley or rope reel; when the wire rope passes through the small pulley or obstacle, it is in the stress state.
7) Damage or fatigue of oil field wire rope during fishing operation:
Causes: improper use of wire rope during fishing operation may cause damage or fatigue.
8) the twist length and diameter of oil field wire rope are reduced
Causes: the wire rope is often overloaded during operation, which causes the organic core of the wire rope to be crushed and damaged.
9) The early fracture of steel wire in oil field wire rope is as follows
Causes: pay no attention to drilling depth, friction heat caused by extrusion and slipping of wire rope.
10) There are serious wear spots on the oil field wire rope
Causes: improper operation during installation and use of steel wire rope causes twisting or bending of steel wire rope; friction of other parts, wear along casing or hard formation, or wear formed during drilling inclined shaft, and even frequent removal of working end can cause local wear.
11) connecting wire rope:
Cause: the connected wire rope cannot be like the whole rope. The joint is easy to loose and produce irregular wear.
12) Linear scratch, fracture, stripping or loose strand of steel wire lead to failure due to rapid fatigue
Cause: the rope is damaged when it passes through the clamping device.
13) The breaking force of oil field wire rope is reduced or damaged
Cause: pay no attention to the wire rope close to the fire source, so that the wire rope is excessively heated.
14) Oil field wire rope deformation:
Cause: improper clamping device or rope clamp, which damages the wire rope.
15) Oil field wire rope bulging:
Causes: the rope passes through the clamping device, improper binding, slow rope feeding or improper connection, twisting, broken line shape and core bulging.
16) Oil field wire rope wear:
Causes: lack of lubrication, clamping device not loosened during rope rewinding, working in sand or hard slag, friction along fixed objects or grinding surface, linear fault, rope groove and pulley size less than the specified size.
17) Fatigue failure of steel wire:
Causes: poor drilling conditions, i.e. high speed tripping and wire rope slipping, cause additional vibration, vibration concentrated on dead line or dead line anchor, rope groove and pulley smaller than the specified size, and improper selection of wire rope structure.
18) Oil field wire rope spiral or crimp:
Causes: during installation and operation, the steel wire rope is allowed to drag or rub on the drill pipe, derrick substructure beam or any other object. When installing the steel wire rope, the requirement that "the diameter of pulley of pulley shall be greater than or equal to 16 times of the diameter of wire rope" is not met.
19) Excessive flattening or crushing of wire rope:
Causes: excessive overload, loose winding or cross winding rope on the drum.
20) The steel wire rope appears wick or bulge
Causes: sudden unloading of wire rope, such as high-speed descent, touching liquid, improper drilling action or violent vibration. The diameter of the pulley used is too small or the rope is threaded around a sharp bend.
21) Oil field wire rope shaking:
Cause: the wire rope is too loose during operation.
22) The oil field wire rope is pinched on the drum
Cause: loose winding on the drum. During drilling, the cutting and replacing scheme of oil field steel wire rope is improper, the drum rope groove or wire rope steering wheel is not properly selected or worn.