The rubber mixing machine is used in the field of rubber and plastic processing, and it has been increasing in recent years. In plastic product factories, people are used to calling it a two-roller machine. On the calender production line, the rubber mixer is before the calender and after the mixer, and its function is to mix and plasticize the uniformly mixed raw materials, so as to provide a more uniform melting material for the calender calendered plastic products. When producing cable material, the milling machine can directly refine and mold the powdered material mixed according to the formula into a molten material, and then compression molded into a sheet-like belt, so that the pelletizer can be cut into granules. On the production line of floor leather, it can directly provide the base coating with uniform mixing and plasticization for the cloth base leather.
The temperature of the mill is an important factor affecting plastic mixing, and the accuracy of the temperature is directly related to the results of ingredient research and development. Since the temperature required for mastication and rubber-plastic blending is much higher than that used for rubber mixing, the rubber mixer used for plastic refining and rubber-plastic blending is mainly heated. Currently, the following three heating methods are used. Type: thermal oil heating, water heating and electric heating. The following are the characteristics of these three heating methodss.
1. Heat conduction oil circulation heating system
In the heating and control of calenders and rubber mixers. This heating method adds a heat conduction oil circulation heating system outside the drum. The whole system is composed of circulating pump in the oil tank, electric heating tube, water cooling tube, temperature measuring element, pipeline, temperature control instrument, electromagnetic control valve and so on. Pumped into the inner cavity of the drum through the rotary joint for circulation.
The heat conduction oil circulation heating system of the rubber mixing machine directly measures the oil temperature through the temperature measuring element, and converts it into an electrical signal and sends it to the control instrument. If the measured temperature is higher than the set temperature, the controller will turn on the solenoid to control the cooling water, and at the same time cut off the power supply of the heater to lower the oil temperature. If the measured temperature is lower than the set temperature, the control instrument will close the solenoid valve of the cooling water pipeline, and at the same time turn on the power supply of the electric heater to increase the oil temperature. Realize roll automatic controltemperature.
2. Water circulation heating system
The principle of the water circulation heating system is similar to that of the thermal oil heating system. In addition to heating the roller, this method can also cool the roller and the processed material. The method is the same as that of a general low-temperature mill. The cavity is cooled by circulation, the cooling water and the heater have no contact, and the two do not affect each other's work. In this way, the open mill can not only carry out high-temperature plasticizing, but also carry out low-temperature strong shear glue, which is more suitable for rubber-plastic blending under the optimum temperature field. It can meet the multi-purpose of one machine under different process conditions for different processing objects. Because this heating method has high heat transfer efficiency, energy saving, and wide process adaptability, it is widely used in rubber and plastics, especially rubber-plastic blending processing.
3. Electric heating system
This heating method is to install several tubular heaters in the inner cavity of the drum. The ultimate purpose of heating materials is achieved by heating radiant heat, heat convection between the inner wall of the drum and the heater, and heat conduction from the inner surface of the drum to the outer surface. Due to the low heat transfer efficiency of the air, the space for installing the heater in the inner cavity of the drum is small, and the volume of the electric heater is limited. This method takes a long time to heat up and is not suitable for large and medium-sized production machines. It is currently mainly used for small test benches.
The heat conduction oil circulation heating system uses high-temperature oil to heat, and the high-temperature oil circulates through the high-temperature oil pump, so that the high-temperature oil circulates in the porous drum to reach a balanced temperature at both ends of the grinding drum, which can greatly reduce the temperature error at both ends and improve the refinement of the product. Accurately help customers win market competitiveness.
