There are two main types of general lubrication methods, one is pre-coated lubrication, refers to the surface of the rough steel wire prior to drawing the surface of various lubricant. The other is the lubrication in the drawing process, that is, in the drawing process to the mold box in the drawing powder. The two have their own characteristics, but the purpose is to make the surface of the steel wire form a lubricating film in the drawing process, these two kinds of methods, and sometimes have to be used together.
1. There are two kinds of pre-coated lubrication:
One is that the pre-coated coating with good lubrication film can be formed in the drawing process, such as fat lime paste, copper plating, borax, phosphating layer and so on. There is also a kind of pre-coating that does not form an effective lubrication film, only to create the preparation conditions for lubrication during the drawing process, such as rusting and coating water lime thin slurry, etc.
The pre-coating for drawing finished steel wire is most commonly used with grease-containing lime paste and phosphating layer, each of which has its own characteristics. The process of pre-coating is usually carried out immediately after pickling.
2. Lubrication in the process of drawing, mainly silk drawing powder, soap powder and grease.
a). Oil suitable for pull-out oil, divided into vegetable oil and mineral oil. Vegetable oil is a very active compound, easy to be adhered to steel wire, good lubricity. However, the formation of a thin lubricating film, and edible resources, so has been rarely used. Mineral oil (oil and spindle oil) is still used in many units. Commonly used as lubricant, generally used for machine lubrication oil No.50, it has good lubricity to wire drawing. If the original lime synovial film is not good, the surface of the wire also scratched phenomenon, it can be coated on the surface of the wire to remedy. But it forms a very thin lubricating film that can only be pulled around two passes. If use machine tool to replace the waste oil, the lubrication effect is better. Because the waste oil contains very small carbonized material, it can improve the lubrication performance. the spindle oil is suitable for the pre-plating drawing of the galvanized steel wire. since the steel wire is not allowed to leave the moisturizing synovium before plating, some use the spindle oil (mixed with the drawing powder to make a paste) when drawing the last two or three passes. It cannot only play a certain lubrication role, but also can clean the last residual lubrication film. However, since the spindle oil is easily vaporized by heat in the die hole, there should be proper cooling measures for the die. At the same time, because the enzyme is very thin, so each pull to add this lubricant.
b) Soap powder
Soap powder is made of sodium soap which is dehydrated and usually used in industrial soap powder. It has good lubrication, but with the increase of drawing speed, its pressure resistance and temperature resistance are not enough, so it has been replaced by drawing powder. However, soap powder and potassium soap (industrial soap) are still used for the lube in the tank.
c). Silk-drawing powder is a metal soap powder, mostly used in mold boxes for dry drawing (a few dissolved in water tanks as a wet-pull lubricant). It is widely used in the drawing of various carbon steel wires. There are two kinds of sodium soap and calcium soap. If the product source, there are two kinds of commercial silk powder and self-made silk powder. Sodium soaping powder, made from fatty acids with caustic sodium (then dehydrated), is essentially a common soap class.
It is readily soluble in water and is suitable for drawing of galvanized steel wire (and water tank use). Because it is easy to absorb moisture, it is not suitable for dry pulling. at present, it is widely used as calcium soap drawing silk powder. it is a bubble product of fatty acid (or grease) and lime powder (after dehydration), insoluble in water, it is a good lubricant for wire dry drawing, and has good lubricating properties, such as pressure resistance, temperature resistance and ductility. but it is not easy to be washed off by water after drawing, so it is not suitable for wire drawing before galvanizing.
