The pipe joint is a detachable connection between the oil pipe and the oil pipe, the oil pipe and the hydraulic components. It should meet the requirements of convenient assembly and disassembly, reliable connection, reliable sealing, small size, large oil passing capacity, small pressure loss and good processing technology. and other requirements. According to the connection method between the oil pipe and the pipe joint, the pipe joint mainly includes welding type, ferrule type, flaring type, withholding type, etc.;
In each form of pipe joint, there are straight-through, right-angle, three-way and other types according to the number and direction of the joints; the connection with the body includes threaded connection, flange connection, etc. In addition, there are some fittings for special purposes.
1. Welded pipe joint
The welded straight pipe joint is mainly composed of the joint body 4, the nut 2 and the nozzle l, and the O-ring sealing ring 3 is used to seal between the joint body and the nozzle. When the joint body is screwed into the body, a metal gasket or a combined gasket 5 is used to achieve end face sealing. For pipes in piping and piping systems
Solder connection. Welded pipe joints have firm connection and reliable sealing. The disadvantage is that welding is required during assembly, so thick-walled steel pipes are used, and the welding workload is large.
2. Compression Tube Fittings
Tube type fitting structure. This kind of pipe joint mainly includes three elements: a joint body 4 with a 24° conical hole, a ferrule 2 with a sharp inner edge, and a compression nut 3 for pressing. When the nut 3 is tightened, the ferrule 2 is pushed into the 24° conical hole and deformed accordingly, so that the ferrule and the inner cone of the joint form a spherical contact seal; An annular groove is pressed out, so as to play a reliable sealing role. The ferrule type pipe joint has the advantages of simple structure, good performance, light weight, small volume, convenient use, no welding, and strict requirements on the axial size of the steel pipe. It has good vibration resistance, and the working pressure can reach 31.5MPa. The ideal pipeline connection in the.
3. Cone seal welded pipe joint
Cone seal welded pipe joint structure. This kind of pipe joint is mainly composed of joint body 2, nut 4 and nozzle 5. In addition to the advantages of welded pipe joints, because its O-shaped sealing ring is installed on the 24° cone of nozzle 5, the sealing can be adjusted. Possibly, the seal is more reliable. The working pressure is 34.5MPa, and the working temperature is -25℃～80℃. The use of such pipe joints is increasing.