Hose Encyclopedia

A tubular rubber product used to transport gas, liquid, slurry or granular materials. It is composed of inner and outer rubber layer and skeleton layer. The material of the skeleton layer can be cotton fiber, various synthetic fibers, carbon fiber or asbestos, steel wire, etc. The inner and outer rubber layer of the general hose is made of natural rubber, styrene butadiene rubber or butadiene rubber; oil-resistant hose is made of chloroprene rubber and nitrile rubber; acid and alkali resistant, high temperature resistant hose is made of ethylene propylene rubber, fluorine rubber or silicone rubber. In recent years, thermoplastic rubbers such as thermoplastic urethane rubbers, polyester rubbers and the like have come to be used. Because of the advantages of easy bending, buffering, light weight and easy installation and use, the hose has a wide range of uses, such as irrigation and drainage in agriculture, dredging in the harbor, and hydraulic systems and pneumatic systems in aircraft, tanks, automobiles and many mechanical equipment., Fuel systems use many hoses.

The inner rubber layer of the hose directly bears the wear and erosion of the conveying medium and prevents its leakage; the outer rubber layer protects the skeleton layer from external damage and erosion; the skeleton layer is the pressure-bearing layer of the hose, giving the pipe body strength and rigidity. The working pressure of the hose depends on the material and structure of the skeleton layer. According to the material and structure of the skeleton layer, the rubber hose can be divided into full rubber hose (without fabric material), cloth-covered rubber hose (the skeleton layer is cloth layer, Figure a), suction rubber hose (there is a layer of metal spiral wire outside the cloth layer, Figure B), braided rubber hose (the skeleton layer is braided steel wire or fabric, Figure c), winding rubber hose (the skeleton layer is steel wire or wire rope winding layer, figure d), knitted hose (skeleton layer is knitted fabric, Figure e), short fiber hose (short fiber and rubber blended and pressed). Among them, the suction hose works under negative pressure, and the steel wire braided hose or winding hose can withstand 80 ~ 600MPa or even higher pressure.

The basic process of hose production is mixed rubber processing, cord (see cord) and canvas processing, hose molding, vulcanization, etc. Hoses with different structures and different skeletons have different processing methods for the skeleton layer and hose forming equipment. Since the full rubber hose does not contain a skeleton layer, it only needs to use an extruder to press out the hose. The fabric-covered hose needs to use a molding machine that wraps the adhesive fabric on the inner rubber layer. When forming the suction hose, it needs to wrap the metal spiral thread before wrapping the inner glue. Braiding and winding hose need to use a special fabric braiding machine or winding machine. Knitting hose needs to use knitting machine, etc.

Hose molding method according to the use of the core or not, can be divided into core method (including soft core method and hard core method), coreless method. The cored method refers to the forming of the hose on the hard core or the soft core, and the coreless method refers to the forming of the skeleton layer and the outer rubber layer directly on the extruded inner hose. In order to ensure that the hose is under pressure during the vulcanization process, the hose is coated with water cloth (soaked wet cloth roll with a width of about 10cm), rope or lead after molding, and then vulcanized. Vulcanization can be direct steam heating or continuous vulcanization. Short fiber hose is the short fiber directly added to the compound, and then press out the molding, its production process is simple, it will gradually replace the knitted hose and fabric hose. Modern hose production process tends to be highly continuous and automated production. The use of thermoplastic rubber or plastic can eliminate the vulcanization process, greatly simplifying the production process.