1. Process defects during valve casting (1) Hole defects, such as pores, shrinkage holes, porosity, slag holes, blisters and iron beans. They may expand into hidden dangers in use. Most of the pores are distributed on the surface of cast iron or near the surface, which are spherical or pear-shaped;

The inch thread is the size of the thread marked in the inch system. According to the shape, it is divided into two types: cylindrical and conical; according to the tooth angle, it is divided into two types: 55° and 60°. The 1/4, 1/2, and 1/8 marks in the thread refer to the diameter of the thread s

valves generally have poor sealing performance. Many buyers and even sellers do not know how to solve them. Now we have five methods to solve the poor sealing performance of valves for reference.(1) Grinding methodFine grinding, eliminating traces, reducing or eliminating sealing gaps, improving the

Ball valveBall valves are evolved from plug valves. It has the same 90° rotation action, except that the plug body is a sphere with a circular through hole or passage through its axis. The ratio of the spherical surface to the passage opening should be such that when the ball is rotated by 90°, all