Fitting Classification
Type | Characteristics | Standard |
Welding tube joint | Welding the tube end of the joint to the tube. The connector body has been connected with the tube end with an end face O-ring. The structure is simple, the manufacture is easy, the sealing performance is good, and the dimensional accuracy of the pipe is not high. The welding quality is required to be high, and the assembly and disassembly are inconvenient. The working pressure can reach 31.5MPa, the working temperature is -25～80℃, suitable for the pipeline system with oil as the medium | JB966～1003-1977 |
interlock connector | Using the deform of the ferrule to connect the tube and seal it, it has advanced structure, good performance, light weight, small volume and convenient use, and is widely used in hydraulic systems. The working pressure can reach 31.5MPa, and the dimensional accuracy of the pipe is required to be high, generally cold-drawn steel pipe is required. The precision of the ferrule is also high. Pipeline system suitable for oil, gas and general corrosive medium | GB3733.1～3765-1983 |
Flare hose fitting | Sealed with the end flares, no additional seals are required. Simple structure, suitable for connecting thin-walled pipe fittings It is suitable for pipeline systems with low pressure with oil and gas as medium | GB5625.1～5653-1985 |
Inserting welding joint | Insert the pipe of the required length into the pipe joint until the end face of the pipe is in contact with the inner end of the pipe joint, and weld the pipe and the pipe joint into one body, which omitted the connection process, while the size of the pipe is required to be strictly suitable for the pipeline system with oil and gas as the medium | JB3878-1985 |
tapered seal welding joint | One end of the tube is tapered male thread with O-ring to be connected with tapered female end of the joint, and is tightened with threads. The working pressure can reach 16～31.5MPa, and the working temperature is -25～80℃ Suitable for pipeline systems with oil as medium | JB/T6381～6385-1992 |
crimped hose fitting | Easy to install, but adds a tightening process. After the hose is damaged, the ferrule of the joint cannot be reused, and it is matched with the steel wire braided hose to form an assembly, and it can be used together with welding pipe joints with O-ring seals. It is suitable for pipeline system with oil, water and gas as medium. Medium temperature: oil: -30～80℃; air, -30～50℃; water, below 80℃ | JB/ZQ4427～4428-1986 |
Three-piece hose connector | There is no need to peel off the cover of the hose during assembly. For hoses with slightly different outer diameters, the compensation depends on the pre-compression of the hose ferrule on the hose. The pre-compression amount of the hose is in the range of 31% to 50% to ensure that there is no leakage under the working pressure, and the rubber will not be pulled out and the outer rubber layer will not be broken. It can be used in conjunction with welding pipe joints, quick-released joints and interlock type pipe joints. It is suitable for pipeline systems with oil, water and gas as the medium. The working pressure and medium temperature are limited by the connected hose. | JB/ZQ4429～4431-1986 |
Quick-released coupling（open and close at both ends） | After the pipe is disconnected, it can be sealed by itself, the liquid in the pipe will not be lost, so it is suitable for frequently disassembly occasions. The structure is more complex, and the local resistance loss is large. It is suitable for pipeline system with oil and gas as medium, the working pressure is lower than 31.5MPa, and the medium temperature is -20～80℃ | JB/ZQ4434-1986 |
Quick-released coupling（open at both ends） | It is suitable for pipeline systems with oil and gas as the medium, and the temperature of the working pressure medium is limited by the connected rubber hose | JB/ZQ4435-1986 |
