defects of molded rubber products

The Main Defects of Molded Rubber Products and Their Adjustment Methods

Table of content

In this blog, we will explain the common defects of molded rubber products. You will understand the cause and solution for each defects.

Ⅰ. Foaming of Molded Rubber Products

1. Causes: The molding material is not completely cured, the air is not cleared, and the mold temperature is too high, which vaporize or decompose a certain component in the material;

2. Solution: Increase the mold temperature or prolong the holding time, increase the number of exhausts, and reduce the mold temperature.

Ⅱ. Lack of Materials for Molded Rubber Products

1. Causes: Too large mold matching gap or too large flash hole, too much release agent, too slow or too fast operation;

2. Solution: Adjust the matching tolerance of the mold and the size of the overflow hole, and adjust the appropriate mold clamping temperature and pressurization time.

Ⅲ. Burnt Molded Rubber Products

1. Cause: The mold temperature is too high, and the rubber has not had time to fully flow during the mold clamping process, and it has been partially vulcanized and lost its fusion ability;

2. Solution: Appropriately reduce the mold temperature.

Ⅳ. Warpage of Molded Rubber Products

1. Causes: Incomplete curing, improper mold ejection process, and over-vulcanization caused by high temperature;

2. Solution: Improve the curing conditions, redesign the mold, and make the ejector device reasonable. Appropriately lower the mold temperature or shorten the vulcanization time.

Ⅴ. The Dull Surface of Molded Rubber Products

1. Causes: Mold temperature is too high or too low, mold sticking, mold surface rough;

2. Solution: Adjust the mold temperature, generally lower the mold temperature appropriately, and use a suitable mold release agent. It should be chrome plated to improve the surface finish of the mold.

Ⅵ. Molded rubber products stick to mold

1. Cause: The molding material is not added with a release agent or is improperly added. The surface of the mold is rough or the new mold is used without grinding, and the pressing pressure is too high;

2. Solution: Add an appropriate amount of effective internal mold release agent through the test to improve the surface finish of the mold, and then press the glass fiber reinforced plastic after testing the mold with compression molding powder, and appropriately reduce the pressure.

Ⅶ. Mottled surface of molded rubber products

1. Causes: Mold overheating, pigments decompose due to overheating;

2. Solution: Reduce the mold temperature.

Conclusion of Defects of Molded Rubber Products

The above content is the cause and solution of the molding of molded rubber products. Pay attention to our company if you want to know more professional knowledge. We are a professional manufacturer specializing in OEM&ODM customization services. We have developed a one-stop solution from mold design and rapid prototyping to mass production based on 40 years of technical precipitation. Welcome to consult if necessary.