The choice of steel wire rope
Select the variety of steel wire rope structure, can be based on GB/T20118-2006 standard in the appendix A "wire rope main use recommended table", in view of the line contact wire rope breaking tension, long fatigue life, good corrosion resistance, it is recommended to give priority to the line contact wire rope. The requirements of the more soft available 6 * 37 class. According to the characteristics of the equipment, for example.
- Elevator, aviation wire rope should be selected with the corresponding professional wire rope
- High lift construction tower rope should be selected with the corresponding special steel wire rope
- Not high lift crane, pile driver, drilling rig, electric shovel, excavator and other machinery with wire rope, require wear resistance, fatigue resistance, good impact resistance, can use 6 × 29Fi or 6 × 36SW structure wire rope
- In the high temperature environment or require the breaking load of equipment, can use metal rope core wire rope
- Shipping, ships, fishing, bundling wood and other steel wire rope, corrosion resistance, soft, can choose 6 * 19, 6 * 24, 6 * 37 and other structures of the A galvanized steel wire rope
In addition, the selection of steel wire rope tensile stress should be based on the use of the load, the specified safety factor, choose the appropriate strength level, should not blindly pursue high strength. In short, should be based on the characteristics of the equipment and operating occasions, choose the right steel wire rope, confirm the safety, extend the service life and improve the economic efficiency of the purpose.
Installation of crane wire rope
- Unwinding:Steel wire rope for high lift construction tower crane etc. should be selected with corresponding special steel wire rope.
- The arrangement of steel wire rope on the reel:The winding direction of the steel wire rope on the reel must be according to the twist direction of the steel wire rope, right twist rope from left to right, left twist rope from right to left arrangement, winding should be arranged neatly to avoid the phenomenon of partial winding or pinch winding.
- Shearing:Wire rope shear win in cutting out two sides 10-20mm apart with wire tie, bundle length for the rope diameter 1-4 times, and then cut off with cutting tools.
Maintenance and inspection of crane wire rope
Steel wire rope in the process of operation should be speed stable, shall not exceed the load operation, avoid shock load.
Steel wire rope in the manufacture has been coated with enough grease, but after running, grease will gradually reduce, and the surface of steel wire rope will occupy dust, debris and other dirt, causing wear and tear of steel wire rope and rope sheaves and steel wire rope rust, therefore, should be regularly cleaned and refueled. Simple method is to choose steel wire brush and other corresponding tools to wipe off the wire rope surface dust and other dirt, the heating melted wire rope surface grease evenly coated in the wire rope surface, also can put 30 or 40 oil spray pour early wire rope surface, but do not spray too much and pollute the environment.
3.Check the record
The use of steel wire rope must be regularly inspected and make a record, regular inspection of the content in addition to the above cleaning and refueling, should also check the degree of wear and tear of the wire rope, broken wire, corrosion and fishing hook, hanging ring, the lubrication wheel groove and other vulnerable parts wear. The abnormal situation must be adjusted or replaced in time.
Extent of wire rope use and end-of-life criteria
1.Fit degree 100%, can be used in important places.
- New wire rope or has been used wire rope, together with the wire position has not moved wear slight and no bulge phenomenon
2.The degree of use 75%, can be used in important places.
- Combined strand wire rope has changed, flattening, bump phenomenon, but not yet exposed steel core or rope core
- Individual parts have slight rust
- The individual steel wire on the surface has spikes (broken head) phenomenon each type of length within the number of spikes is not more than 3% of the total number of steel wire
3.The degree of conformity 50%, can be used for secondary premises.
- Individual parts have obvious rust marks
- The rope strand projection is not very dangerous, the rope core is not exposed
- individual wire rope surface has spikes, no meter length within the number of spikes is not more than 10% of the total number of wires
4.The degree of conformity 40%, can be used for unimportant premises or auxiliary work
- The wire rope has obvious distortion, the rope stock and steel wire has part of the displacement, has obvious protrusion phenomenon
- The wire rope all have rust marks, after the rust marks are scraped away, there are dents on the wire
- The individual steel wire on the surface of the wire rope has the phenomenon of spikes, the number of spikes within each meter length is not more than 25% of the total number of wire rope
- Mechanical damage caused by running loads on sharp protrusions
- Local wear caused by friction with the support structure
- Fatigue breakage due to narrow wear bands, caused by the rope running in too large groove or by too small support reel
- Two parallel broken wire diameter indicates that the wire rope from too small rope groove bending through
- Severe wear, and high radial pressure related
- Friction caused by the same direction twist wire rope serious wear
- Severe corrosion
- Internal corrosion but almost no external damage
- Typical bending fatigue wire breakage
- Wire breakage on the contact surface of the strand or core, different from "crown" wire breakage
- Wire fracture under high stress
- Wire protrusion, caused by torsional imbalance and / or impact loading
- Typical examples of local breakage and deformation
- Birdcage-like protrusion caused by torsional imbalance
- Core protrusion due to torsional accumulation
- Severe wear and internal corrosion