1. Check the condition of mold opening and closing under low pressure

The mold is divided into fast, medium and slow opening and closing 3 times each, and there is no abnormal sound or blocking phenomenon in the opening and closing process;

Mold opening and closing action is smooth, there is no interference.

2. Inspection of mold ejection system (under low pressure)

The ejection action is divided into fast, medium and slow ejection 3 times each to check whether there is any abnormal phenomenon;

Whether the thimble (cylinder) at the plane will be loosened or stuck after ejecting it;

Inclined thimble or cylinder device, with or without positioning pins (to prevent loosening or rotation);

Ejector system (thimble or ejector block) ejector abnormal sound and chatter.

3. Check mold reset

The mold is reset 3 times each at fast, medium and slow speed to see whether it can return to the position (reset);

After reset, the end face of the inclined thimble should not be higher than 0.1mm or flush with the die core;

Whether the contact with the limit card is good for reset;

Whether the ejector needle interferes with the action of the row bit (whether the slider returns to the position);

Whether the mold is equipped with a thimble reset device (mechanical).

4. Check the action of the row bit (slider)

The mold is opened and closed 3 times by fast, medium and slow respectively to observe whether the action of the line position is smooth;

Whether the line position is normal and whether it interferes with the thimble;

Whether the line positioning is reliable;

The sequence of action of hydraulic core-pulling device;

Whether the row bit is strained or "stuck" during empty running.

Second, cavity injection balance test

Play 5 molds successively and weigh their weight;

Record the individual weight of each product in each mold;

Reduce the injection volume, and fill 20%, 50%, 90% of the sample 3 molds each;

Weigh and record the weight of each of the above products;

It is acceptable if the difference between the maximum weight and the minimum weight of the product is less than 2% by weight; If the weight fluctuation error is less than 2%, it indicates that the injection into the cavity is balanced, otherwise the injection is unbalanced;

If it is a single cavity mold, it is also necessary to do the glue balance test (to observe the actual glue situation).

Third, the pressure holding time (gate freezing) time test

When the holding time is first set to 1 second, each molding 3 mold products;

As shown in the table, increase the pressure holding time in turn, reduce the cooling time, so that the entire cycle is unchanged (until the gate freeze sealing glue, product weight does not increase);

As shown in the figure below, set a number of different pressure holding times, mold 3 products each time, weigh the product weight of the specified cavity, and record the data in turn in the table;

Determine the best holding time according to the chart.