Correct crimping of hydraulic hose fittings is essential to ensure the safety and normal operation of the hydraulic system. The following are the detailed steps:
⒈. Preparation of work
Tools and materials to prepare
tools: you need a professional hydraulic hose crimping machine, its pressure and die size should be matched with the hose and fittings. At the same time, prepare calipers, cleaning tools (such as rags, cleaners) and so on.
Materials: Hydraulic hose to be crimped, suitable fittings (make sure that the fitting type matches the parameters of the hose ID, OD, and working pressure).
Inspection and cleaning
Inspection of hoses and fittings: Carefully check hydraulic hoses for breaks, cracks, aging, etc. For fittings, check that their internal passages are clear, the sealing surfaces are flat, and the threads are intact.
Cleaning: Thoroughly clean the outer surface of the hose and the inner and outer surfaces of the fittings with a clean rag and appropriate detergent to remove impurities such as oil, dust and rust. Because any impurities may affect the sealing effect, resulting in leakage of the hydraulic system.
⒉. cut the hose
Determine the cutting length: According to the actual installation requirements, use calipers to accurately measure and determine the cutting length of the hydraulic hose. Ensure that the length is sufficient to connect the two ends of the equipment, while avoiding too long to cause the hose bending radius is too small or too short to install.
Cutting operation: Use special hose cutting tools to cut, avoid using scissors and other tools that may deform the hose port. The cut hose port should be flat and perpendicular to the hose axis, and there should be no burrs, cracks and other defects at the port. If there are burrs, remove them by gently sanding with fine sandpaper.
⒊. Preassembled Fitting
Lubrication (optional): Apply an appropriate amount of special hydraulic lubricant to the insertion portion of the fitting (usually the portion that is sleeved inside the hose). This aids in the insertion of the fitting, reduces friction during installation, and provides some protection to the internal structure of the hose.
Inserting the Fitting: Insert the fitting slowly and smoothly into the hydraulic hose port, making sure that the fitting is fully inserted into the predetermined position. This position is usually marked or determined by the design dimensions of the fitting and hose. During insertion, avoid skewing the fitting to avoid damaging the hose or causing uneven subsequent crimping.
⒋. the crimping operation
1.To select the appropriate mold: according to the size of the hydraulic hose and fittings, the corresponding crimping mold installed in the crimping machine. Different models and sizes of hose and fitting combinations require the use of different molds, the use of the wrong mold may lead to poor crimping or damage to the hose and fittings.
2.Adjustment of crimping machine parameters: According to the material of hoses and fittings as well as the working pressure requirements, adjust the pressure and stroke of the crimping machine and other parameters. Generally, hydraulic systems with higher working pressures require higher crimping pressures to ensure a strong and reliable connection between the fitting and the hose.
3.Perform crimping: Place the hose with pre-installed fittings into the working area of the crimping machine and make sure the position is accurate. Start the crimping machine and crimp according to the set parameters. During the crimping process, the mold of the crimping machine will apply even pressure to the hose and the coupling, so that the metal part of the coupling and the hose will closely fit together to form a reliable connection.
Observe the crimping process to ensure that the crimping machine is working properly and that there are no abnormal sounds or vibrations. After the crimping is completed, check the appearance of the crimped part, it should show uniform deformation, no obvious cracks, wrinkles or other defects.
⒌. Quality inspection
Appearance check: carefully check the joints and hoses after crimping to ensure that the appearance of the crimped part is intact, without cracks, excessive deformation, metal and rubber separation and so on. The metal ferrule at the crimping place should be tightly fitted on the outer surface of the hose, and the edge is neat.
Size check: Use calipers to check whether the outside diameter after crimping meets the requirements. If the outside diameter is too large or too small, it may affect the installation and normal operation of the hydraulic system.
Sealing test: If conditions permit, conduct a sealing test on the crimped hydraulic hose fittings. One end of the hose can be blocked, at the other end of the access to the test equipment, filled with a certain pressure of the liquid (usually hydraulic oil), to observe whether there is leakage. The test pressure should be increased according to the working pressure of the hydraulic system, generally 1.2 - 1.5 times the working pressure, but shall not exceed the rated pressure of the hose and connector.
