Car feed inlet - Function of the hard pipe assembly
The main function of the car inlet pipe assembly is to serve as a rigid channel for fluid (fuel, coolant, brake fluid, etc.) in the transportation system, ensuring the stable and leak-free transmission of the medium under high pressure, vibration, and temperature changes. It is not a single part but a pipe assembly composed of hard pipes, joints, and fixatives, with the core responsibility being "pressure retention, sealing, and vibration resistance".
Specific functions breakdown:
Pressure transmission and pressure-bearing: The hard pipe body needs to withstand the high pressure within the system. For example, the brake hard pipe transmits the hydraulic pressure of the brake fluid, and the high-pressure hose can withstand pressures of over 1000 Bar. The multi-layer structure of the pipe wall (such as the steel wire reinforcement layer) ensures that it does not burst or deform under high pressure.
Medium transportation and corrosion resistance: The inner wall directly contacts fuel, coolant, or brake fluid. The material must be corrosion-resistant and have low permeability. For example, the fuel pipe uses a multi-layer composite structure of fluororubber and polyamide, which not only prevents fuel leakage but also meets the standards of Euro VI emissions.
Connection and sealing: The hard pipe is connected to the pump, valve, and actuator through joints. The sealing form of the joint (such as flared type, sleeve type, O-ring) determines the sealing performance of the system. Failure of the connection will lead to leakage, affecting the safety of the entire vehicle.
Anti-vibration and fatigue resistance: During vehicle operation, there is continuous vibration. The hard pipe avoids resonance frequencies through fixed clasps and path design, and adopts spiral structures or enlarged rounded corners at bends to prevent fatigue cracking.
Temperature resistance and environmental adaptability: The engine compartment has high temperatures, so the hard pipe needs to be resistant to high temperatures (such as fuel pipe with a temperature resistance of over 130°C). The material does not become brittle at low temperatures and can resist external erosion such as road salt and gravel impact.
It should be noted
The hard pipe components of different systems cannot be interchanged. The requirements for materials and pressure resistance in the braking, fuel, and cooling systems vary greatly. When repairing or replacing them, the components need to be selected according to the vehicle model and system.
Plastic hard pipes (such as glass fiber reinforced PA66) are widely used in the cooling systems of new energy vehicles. They are lighter and more corrosion-resistant than metals, but they may undergo hydrolysis and aging after being soaked in coolant for a long time. Regular inspections are required.
The failure of the hard pipe components at the vehicle intake port is most commonly manifested as joint leakage, pipe cracking, and vibration fatigue fracture. The symptoms at different positions vary greatly. The troubleshooting should be carried out step by step according to the type of fault and the location.
Common Fault Types and Symptoms
Joint Leakage: The sealing surface of the quick connector loses pressure, causing leakage of coolant or oil. Oil stains and wet marks can be seen on the surface. When the air conditioning pipe joint leaks, the cooling performance will deteriorate, and when the oil pipe joint leaks, oil drips on the ground.
Pipe Cracking: The bending angle of the hard pipe or the root of the joint cracks under the vehicle vibration, which is more common in motor cooling pipes and intercooler intake pipes. After cracking, power loss, acceleration difficulty, and increased fuel consumption occur, and the fault light may be on or off.
Aging and Corrosion: Long-term high temperature causes the silicone rubber pipe to harden and crack, the metal pipe to corrode and perforate, or the pipe wall to become brittle and the pressure resistance margin to narrow due to long-term immersion in coolant.
Pressure Abnormality: When the pressure of the cooling system is too high, the water pipes expand or burst. This is common when the water pump fails, the cooling system is clogged, the coolant is insufficient, or the electronic fan does not work.
Troubleshooting and Handling Suggestions
First, visually inspect: Check if there is any deformation, wet marks, cracks, or bulges along the entire pipe section. Focus on inspecting the bending angles and the root of the joints.
Then, check the seals and pressure: When there is joint leakage, check if the sealing ring is aged and the end face is flat; when the pipe bulges, check if the system pressure is too high.
Emergency Handling: For minor leaks, you can temporarily rescue by wrapping with rubber or tape and clamping with a clip. However, it is necessary to go to the repair shop for handling as soon as possible. For oil pipe joints leaking oil, you can wrap with cotton yarn and tighten the nut, or apply sealing material.
Replacement Principle: If the cracking is severe or the joint is severely damaged, replace the new part directly. Select the original factory specification or appropriate accessories to ensure that the pipe diameter, bending angle, and interface size are consistent. During installation, clean the interface and avoid excessive bending.
Special reminder
After the intake pipe joint breaks, the fault light may not illuminate. It depends on whether there is air leakage and the condition of other components. One should not judge solely based on the light.
The cracking of the cooling hard pipe is more dangerous in new energy vehicles. Liquid leakage may drip onto high-voltage components, causing insulation problems. It needs to be dealt with first.
The presence of a small amount of engine oil in the intake pipe of the intercooler does not necessarily mean that the turbocharger is broken. It could also be due to the crankcase ventilation system, dirty air filter, or prolonged idling.
If the fault light has already illuminated or the power has significantly decreased, it is recommended to go to a repair shop as soon as possible and use professional equipment to conduct pressure tests and leak location. Do not drive with the problem for a long time.
If you want to know more, keep reading the other articles on this site!
Please call us if you need such products.
Zhuo Meng Shanghai Auto Co., Ltd. is committed to selling MG&MAXUS auto parts welcome to buy.
