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The Process Of Mold Testing

Update:19-10-2020
Summary:

Through a long time working, it's a delightful time for […]

Through a long time working, it's a delightful time for mold testing to check the product completeness and production smoothly. So for the mold trial, there are many steps that need to prepare:

1. Running mold to check the movement

*Under low pressure, checking the mold opening three times with fast, medium, and slow speed if there is any abnormal sound and smooth or not.

*Under low pressure, checking the ejector system three times with fast, medium, and slow speed if there is any abnormal sound. Also checking if there is a locating pin to avoid jam when ejecting.

*Checking the mold reset three times with fast, medium, and slow speed if the mold can return back. After resetting, the angle ejector pin should be the same level of mold core or not more than 0.1mm higher. Checking if there is any mechanical resetting device on the ejector pin.

*Checking the slider three times with fast, medium, and slow speed if smoothly working, and there is no interference with the ejector pin. And the sequence of the core-pulling system should be correct.

 

2. Checking the homogeneity of material into mold cavity gate

*Testing mold five times continuously, weighing the product, and recording all data of each piece. Then reducing the shot capacity three times be full of 20%, 50%, and 90%, weighting, and recording all samples.

*If the difference of weight between maximum weight and minimum weight less than 2%, the material can flow evenly into the cavity; if not, the flow is not evenly. Even for a single cavity mold, also need this test to check the actual material flow.

 

3. Checking the holding pressure time(gate freeze time)

*Firstly setting 1 second of holding pressure time and producing three shots.

*Then successively adding holding time and reducing the cooling time until the gate freezing with the same cycle time.

*Last according to the data, choosing the best holding pressure time.

 

4. Confirming the best clamping force

*Under the condition with best holding pressure and location, setting the clamping force into 90% of maximum clamping force, and producing three shots with recording the weight.

*Successively reducing the clamping force with 5 tons each time and producing three shots until the weight is higher than 5% and there is flash on the product. It's the best clamping force.

 

5. Confirming the best cooling time

*Under the condition with suitable injection parameters, estimating the cooling time(firstly choosing a longer cooling time to make the product cool completely), and producing three shots to measure the product size.

*Each time reducing 1 second cooling time in three shots until there is deformation on product and diminution on size.

*For each piece, should leave around 15 minutes to make the product cool sufficiently, then can measure the size.

*Considering the product size stability to choose the best cooling time.

 

6. Testing the homogeneity of mold cooling

*Using mold temperature measuring instrument to measure 10 points of each cavity and core, then recording.

*If the difference of temperature between each point actual and average temperature less than 2℃, the cooling performance is well; if not, should adjust the cooling system.

 

 

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