Zhejiang Shifang Pipe Industry Co.,Ltd

Zhejiang Shifang Pipe Industry Co.Ltd is one of the most professional manufacturer and exporter of roof drainage system..

What should we do if the product is not satisfactory?
- Sep 20, 2018 -

This is a common problem, but it is also easy to solve. When it is really impossible to solve the problem by means of technological means, the improvement can be considered from the mold design and manufacture, which can be generally solved. It

Skills: when you have such problems, you should observe the movement of the screw of the injection molding machine while molding. Special attention should be paid to the location of the screw when the pressure is complete and when the glue is finished. Such

In the first case, the screw melt position of the injection molding machine reaches the set value, and the position is 0 (residual glue content is 0) when the injection molding is finished. The possible causes are:

1. Leakage of glue. In this case, first of all, should immediately check whether there is glue leakage in the barrel of the injection molding machine; injection molding machine nozzle and the main bushing of the mold is the match between glue leakage. If there is any glue leakage, it is a natural phenomenon that the product is dissatisfied with glue. The following inspection is carried out only if the leakage of molten rubber is confirmed. It

When the product is dissatisfied with glue and no colloid leaks, it may not be enough glue. It is necessary to increase the gel travel and increase the amount of glue. After increasing the melt stroke, we should continue to observe the screw residual glue quantity, melt stroke and the glue situation of the product while injecting. It

2, the amount of glue is not enough. After adding the gel stroke, the product is added to the glue, indicating that the glue quantity is not enough, and it is necessary to continue to increase the gel travel. When the glue stroke reaches the maximum, the product is still dissatisfied with glue, so the large number of injection molding machine needs to be replaced. Such

3. Leaky glue over glue mesons. If the amount of glue in the product does not increase with the increase of the melt stroke, the glue leakage may be caused by the overglued meson in the injection molding machine. It

The method of checking the glue leakage of the meson is to retain the product of a certain injection cycle in the mold cavity and to use manual glue injection instead. The injection pressure increases from small to large, and the leakage of gluon mesons can be judged by observing the advance of the screw. If the screw does not move forward when it is manually glued, it indicates that the rubber seal is good and no leakage. At higher injection pressure, the screw has a small amount of forward, is allowed, this time is not melt leakage, but melt pressure caused by what kind of shrinkage. It

If the product is not satisfied with glue, we must first check whether glue leakage occurs between the barrel of the injection machine and the injection machine nozzle mold; secondly, we must check whether glue leakage occurs in the glue-passing meson at the front end of the injection machine screw. Only after excluding these two situations, can we make other judgments. The following judgments are based on excluding these two situations, no longer recite. Such

In the second case, the screw of the injection molding machine can reach the set melt stroke, but not the set injection stroke (with residual glue). This situation means that there is a glue in the barrel, but it will not enter the cavity. The possible causes are:

1, the fluidity of melts is not enough.

The fluidity of melts is not enough, and the flow resistance is large. This may be caused by:

A) the fluidity of the raw material itself is poor.

B) the processing temperature of the barrel is too low or the temperature does not reach the set value, for example, the temperature display is not true. It

C) Low mold temperature, although the colloid in the barrel fluidity is good, but the flow into the mold runner, cooling too fast, in the mold runner cavity fluidity is poor, resulting in unsatisfactory filling. Such

2. Improper setting of injection process parameters.

Injection pressure is low, the colloid can not overcome the resistance of filling; low injection speed, filling melt gel cooling time is long, fluidity is reduced, resulting in a large resistance to filling; short injection holding time, the product is not filled before stopping filling, etc., will lead to unfilled products. Such

3. The filling channel is blocked.

Because the cold glue, impurities or other substances blocked the channel of filling glue and lead to the glue can not be filled, but also lead to product dissatisfaction glue. At this time it is necessary to check whether the injection machine nozzle, mainstream channel, diversion channel, gate and so on are unobstructed, if there is blockage, it needs to be cleaned up. It

4, the mold gating system is defective.

The defects of the mold gating system are divided into the following aspects:

A) the flow path is too small, too thin or too long, which increases the fluid resistance.

B) there are scars or sharp corners in the runner and gate, which cause poor surface roughness and poor material flow.

C) if the cold well is not set properly or is not set up, the cold glue is not collected completely, resulting in blockage of the runner or gate.

D) improper gate location or number, filling resistance is greater than injection pressure, colloid can not fill the mold; e) mold exhaust bad or improper location of exhaust, mold partial trapped air resulting in product filling unsatisfactory. It

5, poor product design.

Poor product structure design, uneven rubber design, too thin part of the glue, resulting in product stuffing dissatisfaction.