Publish Time: 2022-03-31 Origin: Site
Calendering is a method of rolling a thermoplastic material that has been plasticized in a hot roller and forming it into a sheet or film. Rubber calenders are machines and equipment used for calendering. The following will introduce you the precautions when using the rubber calender.
Here is the content list:
What should we do if an abnormality occurs when using a rubber calender?
Precautions for calendering with rubber calender machines.
1. If an abnormal situation occurs during operation, the confidant of the rubber calender should be stopped, the power supply should be disconnected, and the mechanics should be notified for maintenance.
2. If a sudden shutdown occurs during operation, the machine should be shut down to check whether the temperature of the main motor of the rubber calender is too high, and the mechanics should be notified for inspection and maintenance.
3. Cooling must be carried out slowly during operation to avoid accidents caused by sudden changes in the temperature of the roller.
4. When using the distance adjustment device of the rubber calender, the adjustment distance between the two ends should not be too different to avoid excessive deflection of the roller journal and damage to other parts.
5. The emergency stop device is an emergency measure used when the main motor equipment and personnel accidents occur. Do not use it during normal parking to avoid affecting the life of the machine. To ensure the reliability of the brake work, the emergency brake should be regularly checked and replaced.
The calendering process of rubber includes making the rubber material into a film with a certain thickness and width; pressing a certain pattern on the film, and covering the fabric as the structural skeleton of the product with a thin layer of glue (such as inserting glue, sticking glue), etc. In formula design, the following points should be paid attention to:
1. The calendering characteristics of various raw rubbers: natural raw rubber has high strength, good roll-wrapping properties, good fluidity, and is easy to rubber calender, followed by butadiene rubber, and neoprene rubber-wrapped rolls have good properties but are highly sensitive to heat. Easy to produce sticky rollers, styrene- butadiene rubber and nitrile butadiene rubber have poor fluidity and are difficult to the rubber calender machine. The calendered film has large shrinkage. No matter which raw rubber is used, it must have a sufficiently low viscosity value to obtain good fluidity;
2. Filler selection: In general calendering with a rubber calender, a certain amount of filler must be added to facilitate the calendering operation. Carbon black, white carbon black, and calcium carbonate are all suitable. Clay is not suitable for use, reclaimed rubber is good for calendering;
3. Adding a softener can achieve a good calendering effect, but it should be selected according to the requirements of the specific calendering operation. The tableting requires the film to have a certain degree of stiffness and not easy to deform. Use a softener with less plasticization: such as ointment, Solid ancient horse resin, asphalt, rosin, etc.;
4. Vulcanization system: Calendering is usually carried out at a higher temperature (90-110℃). The choice of the vulcanization system should first consider not easy to scorch. Usually, the Mooney scorch time of the calendered compound should be controlled above 20-25 minutes.
Many things need our attention when using a rubber calender. If you need such related products, you can choose Qingdao Huicai Machine Manufacture Co., Ltd.