①Pipe Fittings card-type pipe fittings pre-installed the most important part of a direct impact on the reliability of the seal. Generally need a dedicated pre-device. Small diameter fittings can be preloaded on the vise. The specific approach is to use a connector as the mother, the nut, card sets pressed to the tube can be. There are card-type straight through the pipe joints, card sets of pass-through through the head,Pipe Fittings card sets of three-way pipe fittings and other types. I found that even the same manufacturers of a number of goods, these types of joint body on the depth of the tapered hole is often not the same, resulting in a leak, and this problem is often overlooked. The correct approach is to connect the end of the tube with what kind of connector body, the corresponding connection with the same type of connector is preloaded, so as to maximize the leakage problem.
② pipe face should be flush. After the saws are cut, they should be polished on the grinding wheel and other tools, and remove the burrs, clean and use high pressure air blowing and then use.
③ pre-installed, should try to keep the tube and the joint body of the coaxial degree, if the pipe deflection is too large will cause sealing failure.
④ preload should not be too large to make the inner sleeve of the tube just embedded in the outer wall of the tube, the sleeve should not be significantly deformed. In the pipeline connection, and then according to the provisions of the tightening force assembly. Ф6-1 card sets of tightening force of 64-115n, 16фmmr 259n, ф18mm for the 450n. If the card before the pre-installed deformation of a serious, will lose the sealing effect.
(B) prohibit the use of sealants and other fillers.
Some people in order to achieve better sealing effect, coated with a sealant on the sleeve, the results of the sealant was washed into the hydraulic system, causing damage to the hydraulic components, such as Yin Ni Kong.
(3) When connecting the pipe, the pipe shall have sufficient deformation allowance to avoid drawing the pipe.
(4) When connecting the pipe, avoid the lateral force, the lateral force will cause the seal to be lax.
(5). When connecting the pipeline, should be a good one, to avoid multiple disassembly, otherwise it will make the sealing performance worse. (2) the length of the need to use a saw or special pipe cutting machine and other equipment to cut off the pipe,Pipe Fittings absolutely not allowed to use the broken (1) according to the requirements of Chapter 9, Such as flame cutting) or grinding wheel cutting; remove the tube inside and outside the round burr, metal chips and dirt; remove the pipe joints rust and dirt; but also to ensure the roundness of the tube; (3) the nut, (4) slowly tighten the nut, while rotating the tube until it does not move, and then tighten the nut 2/2, and then tighten the nut, and then tighten the nut 2 / 3 to 4/3 laps; (5) open check the card holder has been cut into the tube, the location is correct. Card holder is not allowed to move axially, can be slightly rotated; (6) check the re-tighten the nut after passing.
Second, the reasons for the leakage of pipe joints
Prevention of leakage at the pipe joints In the hydraulic system, both metal fittings and hose couplings are prone to leakage problems. For the tube-type pipe fittings, mostly due to the pipeline by a larger external force or impact force, so that the sleeve sleeve loose or deformation of the tube surface caused by leakage, this time should check the card sets are rounded, the edge of the defect, Intact and the degree of compression of the nuts, etc., but also to eliminate the pipeline external force. For the flared pipe joints,Pipe Fittings mostly due to flaring too much, the quality of substandard requirements or multiple demolition, resulting in flaring deformation or cracks caused by leakage, then the front cut off the re-flush. If the use of male and female cone pressure to seal,Pipe Fittings the leakage is mostly due to damage to the two tapered surface, grinding sand can be used to grinding the cone. In some cases with "о" ring by the end or outer diameter of the seal, the reasons for the following leakage: "о" ring aging or deformation caused by leakage; "о" ring assembly is not in place, so that the two plane When the pressure is not flat or "о" ring is cut to cause leakage; "о" ring is not compaction, lack of elastic deformation caused by leakage; "о" shaped ring mouth too deep and cause leakage. In this regard, the need to re-select the same diameter and cross-section of the "о" ring, can also be with the mouth of the sealing plane for cutting or grinding to reduce the depth of the mouth, so that " The ring has enough elastic deformation (compression should generally be between 0.35-0.65mm). For the use of oil-resistant rubber sheet,Pipe Fittings wool felt, soft steel cardboard, combined sealing gasket or sealant pipe joints leak, no matter what material, first of all to check the seal for damage, deformation, aging and roughness is too large and so on , And then take the appropriate measures.
Third, the installation of high pressure hose connector precautions
(1) the hose can not be bent or moved at the root at least 1.5 times its diameter when moving or resting; (2) the hose can not be pulled too tight when moving to an extreme position. (4) the hose as far as possible away from the thermal radiation components, the necessary fashion insulation board; (5) should avoid the external damage to the hose,Pipe Fittings such as the use of the same component on the surface of the long-term friction, etc .; (3) to avoid the deformation of the hose; 6) If the hose itself caused by excessive deformation, should have a support.