What are the characteristics of phosphate coated steel wire rope?

The output scale of domestic steel wire rope industry ranks first in the world. Phosphatized coated steel wire rope is also a Chinese patent. The world first uses surface treatment technology to suppress fretting fatigue, which is the technical development direction of steel wire rope industry.

The commonly used steel wire ropes include phosphating coated steel wire rope, galvanized steel wire rope, stainless steel wire rope or plastic coated steel wire rope. They are used in atmospheric environment. The manganese phosphating coated steel wire rope produced by patented technology has the longest service life, and the hot-dip galvanizing phosphating double coating steel wire rope is preferred in heavy corrosion environment.

Summary of phosphating coating steel wire rope technology

The patented technology of phosphating coated steel wire rope, referred to as phosphating steel wire rope for short, phosphates the steel wire for rope making. The phosphating film makes the steel wire surface more wear-resistant and improves its corrosion resistance. The porous structure of phosphating film can increase the storage capacity of grease on the steel wire surface for rope making, reduce the friction coefficient, promote sliding, delay the occurrence of fretting damage on the steel wire surface, inhibit the initiation of fatigue microcracks, and greatly extend the service life of steel wire rope.

Phosphating technology is mainly used for rust prevention of steel materials, friction reduction in cold processing, wear resistance improvement, bonding of mesophase, electrical insulation and surface decoration. Among them, phosphating process, which mainly plays a role in improving the wear resistance of steel materials, reducing friction and improving lubrication, is widely used in friction bearing parts in the fields of automobile, light industry, chemical industry, electrical appliances, national defense and so on. The phosphating technology is applied to the wear resistance, friction reduction and rust prevention of the steel wire in the steel wire rope. The composite effect of phosphating film and grease on the surface of the steel wire is far better than any kind of grease currently used.

Wear is the most common damage mode of steel wire rope, which is generally divided into external wear, deformation wear and internal wear. Fretting fatigue damage is closely related to the surface properties of materials. The use of surface engineering technology can improve the fretting fatigue resistance of traditional materials and enhance the fretting fatigue resistance of new materials; By means of surface modification, the anti fretting damage performance, wear resistance and anti fretting damage performance of the material can be effectively improved. Taking these surface protection measures is beneficial to weaken or block the harm caused by the friction force during the relative sliding between the steel wires, so as to inhibit and delay the occurrence of fretting damage on the steel wire surface, and greatly extend the service life of the steel wire rope.

Phosphating film itself has good electrical insulation, which can effectively inhibit the formation of micro cells on the surface of steel wires; The joint action of phosphating film and grease can greatly improve the lubrication effect between steel wires and the corrosion and oxidation resistance of steel wires. The patented technology of phosphating coated steel wire rope is to phosphatize the rope making steel wire and control the film weight between 3g/m2-60g/m2, including carbon steel wire, alloy steel wire, galvanized, aluminized, zinc aluminum alloy coated steel wire, etc.

Comparison of production processes of phosphatized coated steel wire rope and smooth steel wire rope (Note: phosphatized coated steel wire rope and smooth steel wire rope are completely different products)

Production process of phosphating coated steel wire rope:

Wire rod → acid pickling → water washing → zinc phosphating → water washing → drying → cold drawing → heat treatment → acid pickling → water washing → zinc phosphating → water washing → drying → cold drawing → rope making steel wire → alkali washing → water washing → acid pickling → water washing → manganese wear-resistant phosphating → water washing → drying → twisting and steel core → rope binding → inspection → packaging

Production process of smooth steel wire rope:

Wire rod → pickling → water washing → zinc phosphating → water washing → drying → cold drawing → heat treatment → pickling → water washing → zinc phosphating → water washing → drying → cold drawing → rope making steel wire → twisting and steel core → rope closing → inspection → packaging

The rope making steel wire is made of high-quality carbon structural steel hot-rolled wire rods. When making, it should be cold drawn to the specified diameter, and at the same time, it should meet certain physical performance requirements. The rope making steel wire produced according to the above process is a smooth steel wire. The rope making steel wire is directly used for twisting strand rope or steel core without any surface treatment after cold drawing, which is a smooth steel wire rope

The service life of phosphated steel wire rope is 2-3 times that of smooth steel wire rope, and it is an ideal substitute for smooth steel wire rope

After phosphating the steel wire for rope making, manganese series or zinc manganese series phosphating is preferred. After phosphating, the steel wire is not subject to any drawing processing, and the phosphated steel wire is directly used to twist the steel wire rope. Because the phosphating coating makes the steel wire surface more wear-resistant, the service life of the phosphated steel wire rope is 2-3 times that of the smooth steel wire rope, and the fatigue resistance of the steel wire rope is greatly improved. The phosphated steel wire rope is not only an ideal substitute for the smooth steel wire rope, And it is fully capable of replacing imported steel wire rope

Application scope of phosphated steel wire rope

Some materials of steel wire will be dissolved in the phosphating process. When the weight of phosphating film is 3g/m2~15g/m2, the diameter of phosphated steel wire is almost unchanged; When the weight of phosphating film exceeds 20g/m2, the added value of steel wire diameter is also very limited, and the mechanical properties of steel wire have no obvious change before and after phosphating (hydrogen removal is required to prevent hydrogen embrittlement). This feature makes the phosphating steel wire rope technology applicable to almost all kinds of steel wire rope products, especially products with more stringent requirements for fatigue resistance, such as elevator steel wire rope, steel wire rope for port loading and unloading gantry crane, mine steel wire rope, aviation steel wire rope, steel wire rope for oil production machine and hoisting steel wire rope for all kinds of cranes, and there is no conflict with the current national standards of all steel wire ropes, That is, the phosphating coated steel wire rope can fully meet the technical requirements of the current relevant national standards for steel wire rope.

Determination of weight of phosphating film

The weight of phosphating film of phosphating steel wire for phosphating steel wire rope shall be tested according to the corresponding national standard gb/t9792-2003 determination of film mass per unit area of conversion film on metal materials gravimetric method. For the twisted phosphated steel wire rope products, the weight of the phosphating film of the steel wire can be inspected by disassembling the strands. First, thoroughly clean the grease applied on the steel wire surface with organic solvent, and then measure the weight of the phosphating film according to the above standard weight method after air drying.