Proper installation and maintenance of hydraulic hose joints and transition joints are key to ensuring the safe and stable operation of hydraulic systems, which can effectively reduce faults such as leakage and wear. The following are specific installation and maintenance points:
一、 Installation steps and precautions for hydraulic hose joints
1. Preparation before installation
Check the integrity of the components:

Confirm that there are no defects such as cracks, deformations, rust, etc. in the rubber hose joints (including the core, jacket, and other components); The inner wall of the hose is free of impurities or damage, and the outer layer is not aged or damaged. If it is a compression type joint, it is necessary to check whether the specifications of the hose and the joint match (such as the inner diameter of the hose, the number of steel wire layers, and the corresponding joint model).
Cleaning treatment:

Rinse the inside of the hose with clean hydraulic oil or specialized cleaning agent to remove impurities such as dust and metal debris; The joint threads and sealing surfaces should be wiped clean with a lint free cloth to prevent impurities from entering the system and causing component wear.
Tool preparation:

Special crimping equipment (such as crimping machine) should be prepared for crimping type joints, and crimping parameters (such as crimping force and crimping length) should be adjusted according to the joint specifications; Suitable wrenches should be prepared for threaded connections (avoid using adjustable wrenches to prevent damage to the edges and corners of the joint).
2. Installation operation (taking common buckle type as an example)
Peel off treatment:

Peel off the outer rubber layer at the end of the hose according to the joint requirements, exposing the inner steel wire layer (be careful not to damage the steel wire). The stripping length should match the step length of the joint core to ensure reliable sealing after crimping.
Assembly joint:

Cover the joint sleeve with the hose, then insert the core into the hose to ensure that the core is fully in place (tightly adhered to the inner wall of the hose), and the steel wire layer is evenly distributed between the core and the sleeve.
Buckling fixation:

Place the assembled joint into the crimping machine mold, align it with the crimping position, and start the equipment for crimping. After crimping, it is necessary to check whether the crimping part is uniform, without cracks, and whether the hose and joint are loose (which can be verified by tensile testing, and generally no relative displacement is allowed).
Connecting hydraulic components:

If the joint is a threaded connection, a suitable sealing material (such as polytetrafluoroethylene tape, be careful not to block the oil hole) should be wrapped around the thread, or a special sealant should be applied (depending on the compatibility of the medium); Slowly tighten with a wrench to the specified torque (refer to the connector manual to avoid thread damage caused by over tightening or leakage caused by over loosening).
3. Check after installation

Observe whether the hose is twisted: After installation, the hose should be naturally straightened to avoid bending angles that are too small (generally, the bending radius should not be less than 8-10 times the diameter of the hose), in order to prevent fatigue cracking of the hose caused by long-term stress.
Avoid interference: The connection between the hose and the joint should be kept away from heat sources and mechanical moving parts (such as gears and chains) to prevent friction, wear, or high temperature aging.
4. Additional precautions for special types of connectors
Quick connector:

Ensure accurate positioning of the male and female heads during installation, and hearing a "click" sound after insertion indicates that the lock is in place; Before disconnecting, it is necessary to release the system pressure to avoid danger caused by high-pressure oil spraying out.
Three petal connector:

During assembly, there is no need to peel off the outer rubber layer. The difference in the outer diameter of the hose is compensated by the pre compression of the outer cover. When tightening the outer cover, uniform force is required to ensure that the three claws have consistent clamping force on the hose.
二、 Installation steps and precautions for transition joints

Transition joints are used to connect components of different specifications (such as thread types and pipe diameters), and the installation core is to ensure "compatibility" and "sealing".
1. Confirmation before installation
Match check:

Confirm that the connection form at both ends of the transition joint (such as metric thread M20 × 1.5 on one end and imperial thread G1/2 on the other end), the pipe diameter (such as the size of the reducer), and the connected components are completely matched to avoid forced installation causing thread slippage.
Sealing form selection:

If it is a tapered thread (such as NPT, PT), it usually relies on the thread to seal itself, and sealant can be applied to enhance the effect; If it is a straight thread (such as M, G), it needs to be matched with a sealing ring (such as O-ring, combination gasket) to ensure that the sealing ring is not damaged or aged, and the material is compatible with the medium (such as oil and temperature resistance).
2. Installation operation
Align connections:

Ensure that the transition joint is aligned with the axis of the two end components during installation, avoiding skewing (especially for large-sized joints), and preventing uneven stress on the threads that may cause breakage.
Step by step tightening:

First, screw the joint into the component thread by hand to confirm that there is no jamming (if the feel is abnormal, it needs to be checked for thread misalignment), and then use a wrench to tighten it to the specified torque (refer to the joint material and specifications, for example, the torque of carbon steel joints is generally higher than that of aluminum alloy joints).
Avoid excessive tightening:

The sealing of threaded connections relies on "moderate compression", and excessive tightening may cause deformation of the joint, damage to the sealing ring, and even lead to leakage.
3. Attention to special scenarios

When installing angle transition joints (such as right angle joints), it is necessary to reserve space for pipeline bending to avoid the joint bearing additional radial or axial forces.
Transition joints used for high-pressure systems require pressure testing after installation (such as holding pressure for 10 minutes to observe for leaks).
三、 Key points for collaborative installation of transition joints and hose joints

When there are both hose joints and transition joints in the system, it is necessary to ensure that the connection sequence is reasonable: generally, the transition joint and hydraulic components (such as pumps and valves) are fixed first, and then the hose joint is connected to avoid stress concentration in the pipeline due to gravity or vibration.
After connecting the hose to the transition joint, it is necessary to check whether the entire pipeline runs smoothly, without twisting, stretching or excessive bending, especially near the moving parts of the equipment (such as oil cylinders and motors), sufficient space should be reserved to prevent the hose from being squeezed or pulled.
四、 Daily maintenance and troubleshooting

1. Regular inspections (recommended at least once a week, with increased frequency in harsh environments)
Appearance inspection:

Check if there is any leakage (oil stains, moisture marks) at the connection between the joint and the hose, and if the joint thread is loose or corroded; Check if the hose has bulges, cracks, or aging (such as hardening or cracking), and replace it immediately if found.
Sealing verification:

When the system is running (especially under high pressure), lightly touch the sealing surface of the joint with the back of your hand to feel if there is any oil leakage (avoid direct contact with high-temperature or high-pressure parts to prevent burns).
Connection status check:

Check if the threaded connection is loose (can be tightened with a torque wrench), and if there are any signs of detachment in the compression type joint (such as gaps between the hose and the joint).
2. Maintenance and replacement
Cleaning and protection:

Regularly clean the dust and oil stains on the surface of the joint with compressed air or a damp cloth to avoid the accumulation of impurities and corrosion; For systems that have been out of use for a long time, moisture-proof cloth should be wrapped around the joint parts to prevent rusting.
Timely replacement of damaged parts:

If leakage, thread slippage, worn sealing surface, or aging or damaged rubber hose is found, it should be replaced immediately (temporary sealing with tape is prohibited). When replacing, it is necessary to replace the components with matching specifications as a whole to avoid mixing different types of connectors or hoses.
Avoid improper operation:

Do not use rubber hoses or connectors as "pivot points" to pry equipment; When disassembling, it is necessary to first release the system pressure (open the unloading valve) to avoid danger caused by high-pressure oil spraying out; After installing the new connector, it is necessary to conduct a pressure test again to confirm that there is no leakage before it can be put into use.
3. Common fault handling
leak:

If there is a leakage at the thread, it may be due to the failure of the sealing material or loose threads. It is necessary to re wrap the raw material tape or replace the sealing ring, and tighten it according to the specified torque; If the crimping joint leaks, it is often due to unqualified crimping or aging of the hose, and it is necessary to re crimping or replace the hose and joint.
Joint fracture:

Due to excessive stress (such as pipeline vibration, skewed installation) or material fatigue, it is necessary to check whether the pipeline is firmly fixed, replace high-strength joints (such as alloy steel material), and optimize the pipeline layout to reduce stress.
summarize

The installation of hydraulic hose joints and transition joints should follow the principles of "cleanliness, matching, and standardization", and maintenance should pay attention to "regular inspection, timely replacement, and stress avoidance". Proper operation can significantly extend its service life and reduce the probability of hydraulic system failure, especially in harsh environments such as high pressure, high temperature, and high dust, where strict installation and maintenance standards are required.