General rubber machinery is the preparation of rubber material or semi-finished machinery, including raw material processing machinery, rubber mixer, extruder, calender, curtain canvas pretreatment device and cutting machine, etc.
Rubber mixing machine
The rubber mixer is divided into two categories: open and closed.
Open type rubber mixer
It is mainly used for rubber thermal refining, pressing, rubber breaking, plasticizing and mixing. It consists of roller, roller bearing, roller distance adjustment device, emergency brake device, frame, frame, transmission device and heating and cooling system, etc. The working principle of the open rubber mixer is that the raw rubber or rubber material is pulled into the gap between the rollers with the help of friction between the two rotating rollers at different speeds, and the strong shear and extrusion effect is used to increase the plasticity. This double roller open rubber mixer has been used in production since 1826. Its structure is relatively simple and is still commonly used in modern times.
Closed rubber mixer
Mainly used for rubber plasticizing and mixing. It has one more mixing chamber than the open rubber mixer (FIG. 1). After the raw rubber and the compound are loaded into the mixing chamber from the hopper, the material door is closed, the top plug of the material pressing device is pressed down, and the two rotors in the mixing chamber turn to each other at different or the same speed. The rubber material loaded in between the rotor, rotor and the mixing chamber by constant mixing, folding and strong kneading effect, resulting in oxidation chain broken, increased the plastic degree.At the same time, the rubber material is dispersed and evenly mixed due to shear action, so as to achieve the purpose of rubber refining. Since the invention of oval rotor closed rubber mixer in 1916, the closed rubber mixer has developed rapidly in the rubber industry, and then other forms of rotor closed rubber mixer. The mixing cycle of modern closed rubber mixer is 2.5 ~ 3 minutes, and the large capacity of the mixing chamber is 650 liters.
Used for extruding tread, inner tube, rubber hose and various rubber strip, also used for covering cable and wire products. Common is the screw extruder. Its working principle is: the rubber material is stirred, mixed, plasticized and pressed in the barrel with the help of the rotation of the extrusion screw, and then moves to the direction of the machine head, and then extrudes a certain shape of the product from the mouth. According to the needs of the product, multiple machines can be used for compound extrusion of various rubber materials. Screw extruder is divided into hot feed and cold feed two kinds. A hot feed extruder usually feeds strips preheated by an open rubber mixer. The rubber material fed by the cold feed extruder does not go through thermal refining, which can save the thermal refining equipment.
It is mainly used for pasting or rubbing curtain canvas, pressing, pressing and embossing of rubber material. The main working part of calender is the roller. The number of rollers is usually 3 or more. When the rubber material with a certain temperature and plastic degree is fed into the gap between the rotating rollers, it is strongly extruded and extended under the action of friction to form the desired product. The first calender was made and used in 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 calender. In order to obtain uniform thickness calendering products, new calendering machines are generally equipped with roller deflection compensation device. The calendered semi-finished thickness is measured by equipment, and some calendering machines are equipped with automatic thickness adjustment systems controlled by electronic computers.