Thread Rolling Cylindrical Dies is also called Thread Rolling Dies, mainly used for external thread processing, specifications include Metric, UNC / UNF, NPT / NPTF, RC / RP, BSW, BSF, Whit.s., Whit., PT & PS, US Tube NPT & NPS, Trapezoidal threads (English and metric) and bicycle threads, etc. Its precision level is classified into levels 1, 2, and 3, It has 2- and 3-Die Systems, so cylindrical Die mechanism can be classified as “Two rollers Die” and ”Three rollers Die”, meaning two or three areas of insertion.

Cylindrical Dies are ideal for a wide range of precision threaded parts. They are made for through-feed rolling and In-feed rolling. The quality of Thread Rolling Dies is stable and directly affects the production speed, yield, and efficiency of threads, and has a significant impact on the overall performance of the product.

specification of thread rolling cylindrical dies

Specification of thread rolling dies

  • D: Outer diameter
  • T: Width
  • d: Bore diameter
  • F: Key-way width
  • H: Key-way depth

Thread rolling cylindrical dies use precautions

  • The accuracy of the screw rolling machine, the vibration is large, and the operation is not working properly.
  • Thread rolling dies is aligned, the axial displacement of the rolling parts is axially displaced, and the screw thread is subjected to two stress of shear and extrusion.
  • The size of the rolled threaded wire blank is uneven, the surface is not cleared, sand wheels, oxidized skin, and dirty products.
  • The hardness of the rolling parts is uneven (8.8 bolts should be at 27~30 HRC; 10.9 should be at 35~37 HRC), preventing the high hardness (50~55 HRC) of the high hardness (50~55 HRC) of the non-backfire (50~55HRC) is mixed due to the harmonizing parts of the high hardness (50~55 HRC) of the non-return fire. In the backfire, its hardness is similar to the hardness of the thread rolling dies, causing a strapping.
  • The lubricant did not add a lubricant when rolling, causing dry friction, so that the temperature of the tip temperature increased to more than the thread rolling dies tempering temperature, the excessive tempering of the screw thread was softened, screw thread stack.
  • Thread rolling cylindrical dies must be fully demagnetized before the factory, and there is no residency, otherwise, it will accelerate the abrasive oil due to the addition of the screw-absorbent fine iron.

How to choose the material of the thread rolling dies?

Thread rolling cylindrical dies is a mold that deforms the metal at normal temperature, and the accuracy requires high. When rolling the metal, the frictional force of a large periodic extrusion and circumferential direction is subjected to a large periodic extrusion, and the working conditions are harsh, and the damage form is: wear, break, and disintegration.

Therefore, the choice of thread rolling dies material is very important. At present, the main materials in the market have Cr12MoVo or CR12, and there are 9SiCr, CrWMn, with high temperatures, river, and high wear resistance, the latter is quenching. Less use. In order to improve steel tissue, improve its toughness, to further increase the wear-resistant thread rolling dies preferably the material is CD53, better than Cr12MoVo, good toughness.