Three heat treatment methods for screws

 　Anchor Bolt, the role of this bolt is to fix the machine on the ground. Because of its strong stability, it is often seen in bridges, mines, railways, highways, power companies, cement plants, automobiles, motorcycles, tower cranes, boiler steel structures, large-span steel structures and large buildings. Screws are one of the important components of the Railway Fastening System, and the hardness of the screws often determines the quality of a mechanical device. The determination of the hardness of the screw is the heat treatment of the screw.

　　There are three kinds of heat treatment methods for screws. Today, I will tell you about the three heat treatment methods of screws.

Anchor Bolt

Anchor Bolt

　　1. Tempering heat treatment: The tempering heat treatment is mainly carried out by induction heating or flame heating. You can use two hardness testers to check the hardness of the screw, and then decide which standard heat treatment to use. The two hardness testers are Vickers hardness. Count and Rockwell hardness tester. In addition to the hardness to determine the score, it can also be selected from the surface heat treatment thickness. For the processing or mass use of the surface heat treatment workpiece, the Vickers hardness tester is selected; when the surface heat treatment hardened layer is thick, the Rockwell hardness can also be used. meter. Different tempering heat treatment standards for internal expansion screws can be intercommunicated, because the conversion value is internationally recognized. After selecting a hardness tester, different scales should be selected, namely HRA scale and HRC scale.

　　2, chemical heat treatment: another heat treatment of the screw chemical heat treatment, it is mainly to infiltrate the surface of the workpiece into one or a few chemical elements of the atom, thereby changing the chemical composition, organization and properties of the surface of the workpiece, so that chemical treatment What effect can I achieve? After quenching and low temperature tempering, the chemical heat treatment can make the surface of the workpiece have high hardness, wear resistance and contact fatigue strength, and the core of the workpiece has high toughness.

　　3, local heat treatment: According to the requirements of different screws, not all screws need to be heat treated, some screws only need local heat treatment, this is the local heat treatment method. For local heat treatment, if the local hardness is high, the local hardening heat treatment can be performed by induction heating. Such parts are usually marked with the local quenching heat treatment position and local hardness value on the drawing.

　　There are still many friends who say that the screws and nuts will not be fixed for a long time. As Anchor Bolt China Exporter tells us that when the screws and nuts are not screwed, we first spray some spray-type lubricants, and then use the wrench to be the most secure. Why do you want to use a plum wrench? Because of this, the nut can be better protected, and the appearance of the nut will not be damaged during the screwing process, and the nut will not be screwed into a circle. When screwing, we also have to pay attention, we have to make a seven-point top three-point screw when the screw head is screwed, use a screwdriver to hold the screw head. Also use a hammer hammer to tap the screwdriver to the upper end, on the one hand, to vibrate the screw, and another method for better screwing. The inner expansion bolts make this wrench and some inspection tools are available. Don't damage your product parts because of small screws. That's not worth the candle.

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