A Simple Introduction of Pipe joints

Pipe joints are components that connect pipes or connect pipes to hydraulic components in hydraulic systems. This is a general term for connectors that can be assembled in a fluid path.

Pipe joints are classified into welding type, bite type, withholding type and flared type.

A pipe joint is a connecting tool between pipes, which is a connection point disassembled between hydraulic component and pipe. It plays an indispensable role in pipe fittings and is one of the two main parts of hydraulic pipes. There are socket welded connection and threaded connection for pipe joints. Pipe joints are mainly used for low pressure pipelines with small diameters, especially for those parts which need to be assembled frequently or which should be finally adjusted in the threaded pipe fittings. We need to adopt metal sealing structure, and gasket seal structures for ordinary pipelines which convey water, oil and air. Gasket seals are made from malleable cast irons. We need to consider requirements of use and prices when choosing pipe joints.

There are many types of pipe joints, and the commonly used pipe joints can be divided into two kinds, that is, hard pipe joints and hose pipe joints. Hard pipe joints have flared type, bite type and welding type three types of connections, while hose pipe joints only have withholding type connection.

Connection types for pipes and pipe joints are different in hydraulic systems. Taper pipe threads can achieve the purpose of seal by screwing the cone-shaped pipe bodies tightly and the use of PTFE materials. Taper pipe threads are mainly used in medium and low pressure hydraulic system. Fine pipe threads have good sealing performance, which makes them often used in the high pressure systems. But when seal the end faces, the fine pipe threads must be used with the help of combined gaskets or O rings. Sometimes we use red copper gaskets, for they are more suitable for connecting pipes with thick wall thicknesses. Pipe joints consist of joint body, joint pipe and nut. In practice, we embed joint bodies in the targets with gaskets that we mentioned above to seal the end faces, seal joint bodies and joint pipes with rubber seal, and sometimes we also use ball surface seal.

Since pipe joints are connecting elements which are detachable. Besides having advantages of firm connection, good sealing, reasonable size, small pressure loss, good process performance, etc., they also need to meet the requirement of being easily detachable. Therefore, do not underestimate a small pipe joint, because only it can support the existence of the entire hydraulic system.