Repair method of screw surfacing machine

 

　　Screw surfacing machine: causes of damage

 

  　 1. The screw rotates in the barrel, and the lubricating oil and compressed gas rub against the screw and the body, so that the working surface of the screw is gradually worn: the diameter of the screw is gradually reduced, and the diameter of the inner hole of the body is gradually increased. In this way, the matching diameter gap between the screw and the body increases a little as the two gradually wear. However, since the resistance of the nose and the manifold on the front of the machine body has not changed, this increases the leakage flow of the squeezed gas forward, that is, the flow of gas and lubricating oil from the diameter gap to the intake direction increases. As a result, the flow rate of the discharge machine decreases.

 

　　2. If there are corrosive substances such as acid in the gas, it can accelerate the wear of the screw and the body.

 

　　3. The abrasion and abrasive material of the machine, or metal foreign matter mixed into the material, causes the screw torque to increase suddenly. This torque exceeds the strength limit of the screw and causes the screw to twist and break. This is an unconventional accident damage.

 

　　Screw surfacing machine: screw repair

 

　　1. The twisted screw should be considered according to the actual inner diameter of the machine body, and the outer diameter deviation of the new screw should be given according to the normal clearance of the machine body.

 

　　2. After the surface of the thread with the reduced diameter of the worn screw is treated, it is thermally sprayed with a wear-resistant alloy, and then processed to size by grinding. This method is generally processed and repaired by a professional spraying factory, and the cost is relatively low.

 

　　3. Overlay welding of wear-resistant alloy on the threaded part of the worn screw. According to the degree of screw wear, surfacing welding 1~2mm thick, and then grinding the screw to size. This wear-resistant alloy is composed of materials such as C, Cr, Vi, Co, W, and B to increase the wear resistance and corrosion resistance of the screw. The professional surfacing factory has a high cost for this kind of processing. Except for the special requirements of the screw, it is generally rarely used.
 

　　4. Hard chromium plating can also be used to repair the screw. Chromium is also a wear-resistant and corrosion-resistant metal, but the hard chromium layer is easier to fall off.

 

　　Screw surfacing machine: body repair

 

　　The inner surface of the machine body is harder than the screw, and its damage comes later than the screw. The scrap of the body is the increase in the inner diameter due to time wear. Its repair method is as follows:

 

　　1. For the machine body with increased diameter due to wear, if there is a certain nitriding layer, the hole in the machine body can be directly bored and ground to a new diameter size, and then a new screw can be prepared according to this diameter.
 

　　2. The inner diameter of the machine is machined and trimmed to re-cast the alloy, the thickness is between 1~2mm, and then finished to size.
 

　　Shanghai Duomu Industry Co., Ltd. is a high-tech industry specializing in power supply development. Welding power supply is my main project. The series of welding machines developed have reached or exceeded the international level. It is well recognized by customers and has a wide customer base. And fame. The products are specialized in welding of precision parts, thin plates, surfacing welding of valves, rollers, picks, etc., welding repair of molds, mechanical shafts, etc., and have been widely used in electronic appliances, coal mining machinery, aerospace and many other fields.