How to maintain injection molding machine in daily life?

Failure cause of die locking structure and prevention of hinge fracture.

1.Excessive clamping force. 

Usually the maximum pressure of the injection molding machine system ids 140 bar, and the maximum stress of the hinged edge is also calculated according to 140 bar. Under normal operation, the hinged edge will have a life of several years. If the system pressure is increased beyond 140 bar, the stress borne by the hinged edge will exceed the safety range and cause damage to the hinged edge.

2.Poor operation 

When the injection molding machine works normally, the mold needs enough clamping force to withstand the strong pressure generated by glue injection, so as not to cause flash or defects of plastic products. If the hinge length is not enough, it will not only increase the quality of the hinge, but also cause the damage to the product due to the insufficient hinge stress, which will lead to flash of the product. Long term flash causes damage to hinged edge.

3.Insufficient lubrication

The machine hinge needs lubricating oil every day to reduce the friction between the hinge edge and the hinge secretary and maintain the normal operation of the hinge edge. If the lubricating oil is not supplemented in time, the hinged edge will be easily burned and broken due to the increase of friction. In addition, if the lubricating oil is replenished regularly, the desired effect may not be achieved. Proper selection of lubricating oil is also necessary, because too thin oil is easy to lose, but too thick oil has insufficient fluidity.

4.Poor design

For example, when the injection molded parts are unevenly distributed in the mold, it can lead to flash of the products and increase the extension of the coring column, causing damage to the hinge edge.

How to prevent failure?

1. The system pressure

If the die pressure is too high, the system pressure should be kept at 140bar and cannot be raised by itself. Some customers often mistakenly think that the mold locking pressure is insufficient. The reason is that when the pressure of the pressure gauge is about 110bar during high compression mold, they mistakenly think that the pressure is insufficient and raise the system pressure more than 140bar. In fact, the clamping force has reached the highest standard. At present, the general pressure gauge has a simple structure and can not respond in time to the rapid pressure change, that is, when the high-pressure mode is locked, the high-pressure pressure pressure rises and decreases rapidly. Therefore, when adjusting the maximum clamping force, the pressure gauge can only be the current pressure of 110bar.

2. Poor operation

When using the injection molding machine, we should first consider installing the appropriate mold. The mold locking force required by the product should not exceed the standard specification of the injection molding machine. The calculation of the mold locking force can refer to the relevant calculation methods.

When adjusting the parameters of the injection molding machine, avoid that the injection pressure is greater than the clamping force, the material temperature or mold temperature is too high, and the injection speed is too fast. In addition, whether the parallelism and rigidity of the mold meet the standards.

3. Insufficient lubrication

Arrange employees to replenish lubricating oil to the hinge edge regularly. In addition, check whether the lubricating pipe and hinge edge have enough lubricating oil from time to time. The oil distributor should be adjusted as much as possible, and it does not cooperate with the oil supply of the hinge. If dirt such as oil hole is found, it shall be cleaned in time. If it is found that the hinge edge is often short of oil and the lubricating oil supply is normal, check whether the through hole on the hinge (steel sleeve) position moves.