Correct operation of an open mill first requires adjusting the roll gap and maintaining its balance. If the roll gaps at both ends are adjusted to different sizes, causing uneven load on the rollers, it is very easy to damage the equipment, which is strictly prohibited. After work, cut off the power and close the water and steam valves.

For safety, before starting the machine, we should follow the following rules:

1. Before turning on the open mill, you must check whether the circuit (current, voltage, etc.), oil circuit (lubrication of reducer, bearings, etc.), and water circuit are normal! Then put on leather wrist guards (wearing gloves is strictly prohibited), wear a mask for mixing operations, and be sure to avoid wearing ropes, belts, rubber bands, etc. around your waist, and it is strictly forbidden to operate while wearing clothes. Carefully check for any foreign objects between the large and small gears and the rollers. Every shift, the emergency brake must be tested to check whether the braking is sensitive and reliable (if it is a knee-touching device, you must get used to contacting the brake device with your knee). During normal operation, the emergency brake must not be used to stop the machine. When two or more people operate the open mill together, they must respond to each other and confirm that there is no danger before starting the machine.

2. The temperature rise speed of the roller preheating must be controlled, especially in the cold winter in the north. When the external temperature of the roller is consistent with the room temperature, if high-temperature steam is suddenly introduced into the roller, the temperature difference between the inside and outside may be more than 120℃. The stress caused by the temperature difference on the roller can reach 130.0～150.0 MPa, which exceeds the U.1=140.0 MPa of cast iron. If the rubber material is added too early, under the combined action of the lateral pressure, the roller is very easily damaged. For safety reasons, preheating should be done without load, and lubrication should be carried out without load. When the temperature rises to or near the set temperature, then add the material. This needs to be emphasized to the operators.

3. The rubber material should also be checked before adding it to the open mill. If it contains hard metal foreign objects, and these are put into the mill with the rubber, causing a sudden increase in lateral pressure, it will cause equipment damage.