According to the application characteristics of automobile brake pipe hard pipes, plastics are divided into general plastics, engineering plastics and special plastics. General-purpose plastics refer to plastics with large output, wide use, good molding, and low prices, such as polyethylene, polypropylene, phenolic and so on. Engineering plastics refer to plastics that can withstand a certain external force, have outstanding mechanical functions, high and low temperature resistance, and have good standard stability. They can be used as engineering structures, such as polyamide and polysulfone. Special plastics have special functions, such as fluoroplastics and silicones. According to the physical and chemical properties, it can be divided into thermosetting plastics and thermoplastic plastics. Thermosetting plastics refer to plastics that can be cured or have insoluble (melting) characteristics under heat or other conditions. The advantages of thermosetting plastics are strength and heat resistance, and they are not easily deformed under pressure; the disadvantages are messy molding technology and low output power. Thermoplastics refer to plastics that can be repeatedly heated to soften and cool to harden within a specific temperature schedule. The advantage is that the molding technology is simple, the yield is high, it has certain mechanical functions, and can be recycled and used repeatedly; the disadvantage is that it has poor heat resistance and low rigidity.

Regular inspection of automobile joint sealing and mechanical protection is the guarantee to ensure the safe and reliable operation of joints. During installation, moisture and moisture should be avoided in the joints. In addition, joint protection grooves or cement protective boxes should be built at the joint position. Generally, the cable body has an inner shielding layer. When we make the connector, we must restore the inner shielding layer of the connector of the conductor part of the crimping tube. A part of the inner semiconductor shielding of the cable must be set aside to facilitate the shielding of the connector on our connecting tube. They are connected to each other to ensure the continuity of the internal semiconductor during use, so that the field strength at the joint is evenly distributed. Speaking of internal semiconductors, there must be external semiconductors. The external semiconductor shielding is a semi-conductive material that acts as a uniform electric field outside the insulation of the cable and the connector. Like the internal semiconductor shielding, it plays a very important role in both the cable and the connector, but the external semiconductor port It must be neat and uniform, and smoothly transition with the insulation. The semiconductor tape is wound at the joint to connect with the semiconductor shielding tower outside the cable body.

For the pressure of the high-pressure hose system, choose the number of layers of steel wire for the hose. The pressure is high and the number of layers of steel wire is large. Each type of hose has a maximum operating pressure, and the explosion pressure of the hose is 4 times the maximum operating pressure. The higher the pressure resistance of the hose, the higher the price, so according to the actual system pressure, the maximum operating pressure of the selected hose should be higher than the actual operating pressure. If the impact pressure of the system is frequent, use a hose that is particularly resistant to pulses. The hydraulic high-pressure hose is the main connecting piece in the hydraulic system and equipment. It can accept high pressure and can be easily disassembled. It is widely used in the hydraulic industry. The hydraulic hose is composed of a rubber layer on the surface and a woven wire layer on the inside. Depending on the receiving pressure of the hydraulic hose, the number of steel wire layers inside is different. Usually, the steel wire layer is from 1 to 6 layers, and the pressure can reach up to 60MPA. . The inner rubber of the hydraulic hose is made of mineral oil, bio-oil, and good swelling composition rubber, and the outer layer is abrasion-resistant and anti-aging rubber. The center is the surrounding layer of high tensile steel wire. Suitable media for hydraulic hoses are: mineral oil, oil-water mixture, polyethylene glycol base oil, composition fat base oil, rapeseed oil, etc.