Shenzhen Shi Shi Tong Metal Products Co., Ltd

The zinc-coated layer of the hexagon socket shoulder screw does not exceed the part (basic size) in the case of external threads. After coating, the ordinary thread is in accordance with the provisions of GB/T 3934: the external thread is inspected separately with the tolerance zone position h or H. When the coated thread is tested with a ring gauge, the maximum allowable torque is: 0.001 (N·m). Where d is the nominal diameter of the thread (mm). Other  socket shoulder screw dimensions  are only applicable before coating. In order to achieve the specified corrosion resistance, if the minimum coating thickness is specified, the thickness range of the zinc coating layer shall be such that the  socket shoulder screw dimensions  is substantially equal to the minimum coating thickness. Therefore, the estimated maximum zinc coating thickness is twice the minimum required coating thickness. See Table 1. The minimum basic deviation of the thread applied for coatin...

Sometimes for some reason, the screw part of the  m10 x 1.25 socket head cap screw  will have a slight bending or obvious bending. The main reasons are: the screw is too long, the material is not hard enough; the transportation process is caused by etc. At the time of assembly, once the straightness of the screw portion exceeds the tolerance, it cannot be used. In this case, how do you measure the straightness of the screw? Method 1: Place the  m10 x 1.25 socket head cap screw  to be measured on the V-frame specified in GB/T 1219 (see Figure 1). Use the dial gauge specified in GB/T 1219 to measure at the Max bend. Turn one revolution and measure the difference in the pointer reading Max, 1/2 of which is the measured value. figure 1 Method 2: Screw the screw of the  m10 x 1.25 socket head cap screw  into the special inspection mold with internal thread (the hole diameter d’=d max +t) by hand, and screw it into 2 turns or more (calculated b...