Moulded rubber goods – an extensive group (around 30,000 items) of gaskets, sealing and shock-absorbing parts (oil seals, rings of various sections, dust-, moisture- and oil-proof caps, rubber-metal shock absorbers, etc.). These rubber goods are obtained by moulding a rubber mixture with its simultaneous vulcanization in a mould installed on a press, or by injection moulding.
The group of non-moulded rubber goods includes products (around 12,000 items) used mainly for sealing windows and doors of cars, aeroplanes, railway wagons, and for sealing joints of building panels, etc. They are made in the form of profiled bundles of various lengths and cross-sections, which are made by extrusion of the rubber compound and subsequent vulcanization of the semi-finished product in continuous devices or in boilers (batch method). Seals can be either monolithic or porous.
Conveyor (conveyor) belts, which are elements of conveyors for various purposes, are designed to move bulk and other materials. The belts are reinforced mainly with fabrics (made of synthetic fibres, cotton, combined) with a breaking force range of 65-300 kn / m, or kgf / cm; for the reinforcement of belts, which must have an exceptionally high strength, a brass-plated steel cable is used. Production technology of rubber-fabric belts includes the assembly of the fabric core on duplicating units, covering the core with a layer of rubber compound of the required thickness on calenders, and vulcanization of the belt in a press, the plates of which are about 10 m long. See also “Conveyor belt”.
Belts, which serve as a flexible element of belt transmission, in engines of automobiles, agricultural machines, and various industrial installations, are divided into flat and V-belts. The flat belts production technology, which is a multi-layer rubber-fabric plate, is similar to the technology for the production of conveyor belts (the plate is cut into strips before or after its vulcanization to obtain a belt of the required width). V-belts have a closed design and a trapezoidal cross-section with the following main details of such belts: the central (bearing) layer of rubberized cord fabric or cord; rubber layer located between the wide base of the trapezoid and the carrier layer (the so-called stretch layer); rubber layer, which is located between the carrier layer and the narrow base of the trapezium (the so-called compression layer); outer (wrapping) tissue layer. Belts are assembled on machines and then vulcanized in a boiler, in a press or special (rotary or diaphragm) vulcanizers; The choice of vulcanizing equipment depends on the length and section of the belt.
Hoses are flexible pipelines used to supply liquids, gases, bulk materials, etc. under excess pressure (pressure hoses) or vacuum (suction hoses). The common structural elements of these rubber products are an inner (sealing) rubber layer, a load-bearing frame and an outer rubber layer. Power frame for sleeves designed for pressure up to 2 MN / m2 (20 kgf / cm2) is a fabric lining; for hoses operated at pressures up to 10 and up to 70 MN / m2 (100 and 700 kgf / cm2) – thread and metal braiding, respectively. The suction hoses [permissible vacuum 80 kn / lg (600 mm Hg)] are equipped with a metal spiral in addition to the power frame. The inner and outer layers of the sleeves are made by extrusion, and the cushioning power frame is applied on assembly machines, thread or metal braiding – on special braiding machines. The assembled sleeve is bandaged with fabric tape or pressed with a lead sheath and vulcanized in a boiler (the tape or sheath is removed after vulcanization).
