10. Refractory powder in mixing
Reason:
1. Less structural dose
2. Excessive low hydroxyl content in structural agents
3. Raw gum has high molecular weight and narrow molecular weight distribution.
4. Silicone Rubber Raw Rubber with Micro-crosslinking in Raw Rubber
5. The proportion of silica to additives is out of proportion 6. Opening or kneading temperature is too low
Handle:
1. Adding Structural Agents
2. Selection of raw rubber with uniform molecular weight distribution
3. Adding in proportion to structural agent during feeding
4. Increase smelting or kneading temperature appropriately.


11. Explosion in Rubber Refining
Reason:
1. Production of methanol, ethanol flammable gases
2. Electrostatic sparks generated by friction during shearing
3. The equipment is not well sealed and the N2 protection is not enough.
Handle:
1. Choose substances that do not produce explosives or have narrow explosion limits as dispersants.
2. The equipment is well sealed.
3. Nitrogen-filled gas isolates oxygen


OPENING MACHINE PROBLEM
Problem 1: Mixed rubber cannot enter roll spacing or force into side to form fragments.
1. The reason why the blend cannot enter the roll is that the shear force between the two rolls of the mill is not enough to destroy the agglomeration of the blend.
2. From the mechanical point of view, the reasons are: slow speed, small speed ratio, small roll diameter and so on.
3. From the point of view of compound, the reasons are: excessive compound, high cohesion of compound (i.e., high viscosity, high speed, structural phenomenon of compound).
Problem 2: Rubber wrapped rollers have poor performance and even take off rollers
1. The roll-wrapping property of the compound is related to the raw rubber strength, breaking-tensile ratio, relaxation time, roll temperature and shear rate of the compound.
2. Increasing raw rubber strength, breaking tensile ratio and relaxation time will improve the performance of roll wrapping, on the contrary, the roll-off will occur.
3. Reducing the distance between rolls, increasing the speed ratio or increasing the speed of shearing can increase the tensile ratio and relaxation time of the compound, and thus improve the roll-wrapping performance of the compound.


Question 3: Rubber sticking roll and hard-to-leave roll
1. Rubber roll-bonding is related to the surface tension of rubber on the roller. The factors related to the surface tension are raw rubber itself, the size and dosage of reinforcing filler, the dosage of softener, the temperature of contact surface, etc. Therefore, in general, gas-phase rubber is easier to stick to the roll than precipitation rubber, and the roll-coating with small roll spacing and production time will make the rubber roll-bonding.
2. Therefore, reducing the roll temperature and adding demoulding agent can improve the phenomenon of roll sticking.