Detailed point. I'd like to add some knowledge about it.
The sleeve type pipe joint has the advantages of simple structure, convenient operation and no need of welding. But in the middle and high pressure hydraulic system, if improper operation, often will cause leakage, and affect its popularization and use. After years of practice, the author summed up some experience, and achieved good results.As shown in the drawings, the sleeve type pipe joint is mainly composed of a joint body 1 with a taper hole of 24 degrees, a clamping sleeve 2 with a sharp inner edge and a pressing nut 3 and three parts which are pressed. Tighten the nut 3, card set of 2 is to promote the 24 degree taper and then deformation, make the card sleeve and the connector body cone to form a spherical contact seal; at the same time, the outer wall of the inner edge of the sleeve mouth embedded on the outer wall of the steel pipe 4, a pressure ring groove, so that the reliable sealing effect. The best choice of steel tube to eliminate stress annealing 20# fine drawing pipe, so that it is beneficial to insert the inner edge of the sleeve into the outer surface of the steel pipe, and play a reliable sealing role.
The ends of the pipe shall be flush. The pipe should be flush in sawing grinding wheel and other tools, and burr cleaning and high pressure air blowing after use.When installing, the coaxiality of pipe and joint body should be kept as far as possible. If the pipe deflection is too large, it will cause sealing failure.The pre assembly force should not be too large. The inner blade of the clamping sleeve is just inserted into the outer wall of the pipe, and the clamping sleeve should not be deformed obviously. When the pipeline connection, and then according to the specified tightening force assembly. The tightening force of the phi 6-10mm card sleeve is 64-115N, Phi 16mmr 259N, Phi 18mm is 450N. If the sleeve is badly deformed at pre assembly, it will lose its sealing effect.(2) prohibit adding sealant and other fillers. In order to obtain better sealing effect, the sealant is coated with sealant, and the sealant is poured into the hydraulic system, causing the hydraulic components, such as damping holes, blocked and so on.(3) when connecting the pipe, the pipe should have enough deformation allowance to avoid the tensile stress of the pipe.(4) when connecting the pipeline, it should be avoided to be subjected to lateral force; the lateral force will cause the seal to be too lax.
(1) pre assembledThe pre assembly of the sleeve type pipe joint is the most important step, which directly affects the reliability of the seal. Special pre assemblies are usually required. The small diameter can be pre joint in a vise. The concrete method is to use a joint body as the mother's body and press the nut and the sleeve tightly onto the pipe. The utility model mainly comprises a sleeve type through pipe joint, a clamping sleeve type end through connection head, a clamping sleeve type three way pipe joint and other patterns. The author found that even if the same batch of goods of the same manufacturer, the tapered holes on these joints are often different in depth, resulting in leakage, and this problem is often overlooked.The correct approach should be to connect the end of the pipe with what kind of joint body, and the corresponding connection end with the same type of joint pre installed, so as to maximize leakage problems can be avoided.
