General rubber machinery is the machinery for preparing rubber raw materials or semi-finished products, including raw material processing machinery, rubber mixing machine, extruder, calender, cord pretreatment device and slitter.
Rubber mixing machine
Rubber mixing machine is divided into two categories, namely, separate type and closed type.
Open type rubber mixer
It is mainly used for hot refining, pressing, breaking, plasticizing and mixing of rubber. The utility model is composed of a roller, a roller bearing, a roller spacing adjusting device, an emergency braking device, a frame, a frame, a transmission device, a heating and cooling system, etc. The operating principle of the open mill is to draw the raw rubber or rubber material into the open mill. With the help of the friction between two rolls rotating at different speeds, the gap between the rolls is increased by strong shearing and extrusion to increase the plasticity. This double roll open type rubber mixing machine was put into production since 1826. Its structure is relatively simple and it is still widely used in modern times.
internal mixer
It is mainly used for plasticizing and mixing of rubber. It has one more mixing chamber than the open mixer (Fig. 1). After the raw rubber and rubber material are loaded into the internal mixing chamber from the hopper, close the material door, press down the top plug of the pressing device, and the two rotors in the internal mixing chamber rotate at different or different speeds. The same speed. The rubber materials installed between the rotor, rotor and internal mixing chamber, through continuous mixing, folding and strong mixing, led to the fracture of the oxidation chain and increased plasticity. At the same time, the rubber material is dispersed and mixed evenly due to shearing, so as to achieve the purpose of rubber mixing. Since the invention of the elliptical rotor closed rubber mixing machine in 1916, the closed rubber mixing machine has developed rapidly in the rubber industry, followed by other forms of rotor closed rubber mixing machine. The mixing cycle of the modern closed rubber mixing machine is 2.5~3 minutes, and the large capacity of the rubber mixing room is 650 liters.
Extruder
Used for extruding tread, inner tube, rubber tube and various rubber strips, as well as covering cable and wire products. Screw extruders are common. Its working principle is: the rubber material is stirred, mixed, plasticized and pressurized in the barrel by virtue of the rotation of the extrusion screw, and then moves towards the die, and then extrudes a certain shape of products from the mouth. According to the needs of the product, multiple machines can be used for composite extrusion of various rubber materials. Screw extruder is divided into hot feed and cold feed. The hot feed extruder usually feeds the rubber strip preheated by the open rubber mixer. The rubber fed by the cold feed extruder is not subject to hot refining, so the hot refining equipment can be omitted.
calendar
It is mainly used for pasting or kneading curtain canvas and pressing, pressing and embossing of rubber materials. The main working part of the calender is the roller. The number of drums is usually 3 or more. When the rubber with a certain temperature and plasticity is fed into the rotating roller gap, it will be forcibly squeezed and extended under the effect of friction to form the required products. The first calender was manufactured and put into production in 1857, and has been continuously improved since then. Especially since the 1950s, the development of plastic industry has strongly promoted the improvement of high-precision and high-speed calenders. In order to obtain calendered products with uniform thickness, new calenders are generally equipped with roll deflection compensation devices. The thickness of semi-finished products after calendering is measured by equipment. Some calenders are equipped with automatic thickness adjustment systems controlled by electronic computers.