Compression Mold Making for Silicone Rubber Gaskets

Basic part information:

• Material: NBR

• COLOR:BLACK

Basic mold information:

• MOLD TREATMENT:Chrome/ Nitriding treatment

• SHRINKAGE:1.75%

• TYPE OF PRODUCT:valve covers/ oil pans / manifold

• MOLD MATERIAL:P20

Before making the compression mold, YEESHINE will make DFM analysis of the rubber part and verify some important information with the customer.

After the verification with the customer, YEESHINE made 3D design layout of the compression mold.

We experience the following problems in the process of making compression mold :

1. Incomplete Filling  

Problem:  

Pressing too fast squeezes rubber out before the mold fills, causing thick flash but incomplete parts.  

Fix:  

Slow down the press speed – let rubber flow slowly into the mold under steady pressure.  

2. Blisters, Bubbles or Spongy Texture  

Problem:  

- Under-curing: Low temperature/short time traps vapors from curing.  

- Low pressure: Trapped air/vapors can’t escape.  

- Fast pressing: Squeezes mold shut before gas escapes.  

Fix:  

- Check and adjust cure time/temperature.  

- Increase pressure slightly.  

- Close the mold slowly with steady pressure.  

3. Tearing During Removal  

Problem:  

Over-cured parts lose elasticity and tear when pulled out.  

Fix:  

Lower cure temperature or shorten cure time – keeps rubber springy for safe demolding.

We finally solved the above problems and successfully produced the products as required by that customer.

Customers are very satisfied with the product results, and gave us other similar project production, while we also have the ability to meet customer needs, to achieve a win-win situation!

Remark by YEESHINE

In the production of automotive rubber parts, the accuracy of the mould determines whether the parts can match perfectly with other parts of the car, thus ensuring the performance and safety of the car.

Yeeshine can customise high-quality rubber moulds to ensure precise dimensions, smooth surfaces and structural integrity.

For the automotive industry's custom gaskets, we can provide services such as precision die-cutting, reciprocating cutting, laser cutting, kiss-cutting and slitting solutions with on-time delivery and we are rated as a trustworthy manufacturer by many of our customers.