How is the steel wire rope made? How does production process quality control affect service performance?

When it comes to "rope", we are all familiar with it. All kinds of ropes can be seen everywhere in our daily life, but our understanding of the important purpose steel wire rope applied in the industrial field is not so comprehensive. Next, we will give a detailed introduction to the important use of steel wire rope.

1. What is wire rope.

How is the steel wire rope made? How does production process quality control affect service performance?

Steel wire rope is a spiral steel wire bundle twisted together according to certain rules, which meets the requirements of mechanical properties and geometric dimensions. Steel wire rope is composed of steel wire, rope core and grease. Steel wire rope is a kind of rope which is first twisted into strands by multi-layer steel wires, and then twisted into a shape by a certain number of strands with the rope core as the center. In, it is used for lifting, traction, tensioning and bearing. The steel wire rope has the advantages of high strength, light weight, stable operation, not easy to break suddenly, and reliable operation. In 1834, European orubt invented the world's first steel wire rope (smooth steel wire rope).

2. How steel wire rope is produced.

We know that the molding and processing of metal materials involves multidisciplinary knowledge. Steel wire rope seems to have a simple structure, but its production and manufacturing process, process and quality control are extremely complex. At the same time, in some specific application fields, such as steel wire rope for mine hoisting, the production and manufacturing of steel wire rope belongs to semi customized production, which means that the product quality of different batches of steel wire rope produced by each factory in different time periods may be different. Therefore, for the users of steel wire rope, It is very necessary to understand the manufacturing process of steel wire rope for how to better select and use steel wire rope. Let's introduce this aspect in detail.

Selection of raw materials

The steel wire ropes used in most important industrial applications are ferromagnetic steel wire ropes, and the raw materials used are high-quality carbon structural steel wire rods. The quality of raw materials directly affects the performance of the finished wire rope, that is, the tensile, bending and torsional performance. In image, it is the anti fatigue performance of the wire rope (the time and frequency of fatigue wire breakage), toughness (whether the wire rope is hard or soft), etc.

As the steel smelting process lags behind western developed countries, the product quality of domestic steel wire rope brand is significantly lower than that of imported steel wire rope brand. However, it is gratifying that in the process of steel wire rope testing in recent two years, we found that the product quality of domestic steel wire rope has been significantly improved. What are the requirements for raw materials in general?

The wire rod is hot rolled from steel ingot, and its chemical composition is generally required as follows:

The steel is made of medium carbon steel or high carbon steel, with carbon content of 0.25% ~ 0.84%, manganese content of 0.6% ~ 0.9%, silicon content of less than 0.35% and phosphorus and sulfur content of less than 0.04%. It should be noted that with the popularization of various refining technologies, vacuum continuous casting technology, electromagnetic stirring technology and other new smelting processes, the content of phosphorus, sulfur, hydrogen and other harmful elements is controlled to meet the requirements of wire rope production, cold brittleness The possibility of hydrogen embrittlement is very low.

The process of making wire rod into semi-finished steel wire is called "blank opening". In this process, wire rod will undergo pickling, water washing, drying, wire drawing and other processes, the diameter of wire rod will be reduced by 90%, and semi-finished steel wire will enter the next process "wire drawing" to make finished steel wire for final strand twisting.

As mentioned above, the rope core in the components of the steel wire rope mainly plays the following roles: supporting the twisting of its outer strand, storing lubricating grease to improve the corrosion resistance of the steel wire rope and reduce the internal wear of the steel wire rope.

The rope core can be divided into the following different materials: fiber core FC (according to the fiber material, it can be divided into natural fiber core NF and synthetic fiber core SF), steel wire core (steel wire core can also be divided into independent steel wire core iwrc and steel wire strand core WMC according to the structure). In the lifting field of our mine, fiber core steel wire rope is mostly used (to ensure better flexibility), and the natural fiber core is twisted by jute, sisal, etc, Synthetic fiber core has the advantages of good corrosion resistance and customized length, so as to reduce or avoid the phenomenon of rope core joint. Wire strand core WMC wire rope is generally used in the field of static load or close to the field of static load, which is characterized by excellent impact resistance. Independent wire rope core iwrc is generally used in dynamic load and high temperature environment.

It should be noted that in the rope making process, the rope core is allowed to have joints, while for steel wire ropes for important purposes, the steel wire for rope making shall not have electric joints.

Obviously, the main function of wire rope grease is to improve the corrosion resistance of wire rope and reduce internal wear. It should have excellent adhesion to metal (it is not easy to throw out the steel wire rope when running at high speed) and good temperature adaptability (Taking Northwest China as an example, the temperature difference between winter and summer is large, so it is required that the steel wire rope grease should maintain a certain viscosity in different temperature ranges). At present, all steel wire rope brands adopt German nyrosten brand, and its models are mainly divided into nyrosten n113 and nyrosten n113fs.