the thickness is uneven
Uneven thickness of silicone rubber products is also common and undesirable, mainly the following points:
- Use silicone or paper sheets to pad molds.
- If the product is too thick, the mold temperature can be appropriately reduced and the vulcanization time can be extended.
- If the drum is due to immature, the vulcanization time can be appropriately increased.
open the glue
Poor opening of the glue is generally a problem with silicone rubber materials, check whether the raw materials have the following problems:
- The plasticity value is small, and the initial viscosity is small
- The glue has mild self-sulfur
- Increase the glue content to solve
the surface spray frost
Silicone products are easy to spray frost, for the following reasons:
- The vulcanization time is not long enough
- The vulcanization system needs to be improved
- The temperature of the mixing roller is too high, and the air temperature or humidity is too large
- The rubber compound is not uniform enough, or the parking time is not enough to cause the compound to be insufficiently dispersed
- The rubber is easy to spray frost after aging
- The upper limit of several combinations of easy to spray frost should be mastered, otherwise it is difficult to avoid frost spraying
the micropores of the rubber parts
The surface of the silicone product produces micropores, if it is an A-class appearance customer is difficult to accept, the main reason for the poor is too much moisture in raw materials, raw materials are used after baking, and the rubber that has been mixed can be solved by adding part of caO.
Silicone products trapped gas will cause great confusion, mainly related to the mold, so the mold design should consider the problem of exhaust.
- Insufficient number of exhausts.
- The mold is unreasonable, and the exhaust groove is opened.
- Secondary exhaust of appropriate products.
- Spray a small amount of glue mold agent.
If the surface of the silicone product is produced with bubbles, the following points can be improved:
- The mold temperature is too high.
- The vulcanization time is too long.
- Increase the number of exhausts.
Improvement method of silicone rubber products that are not cooked
- The temperature is not high enough.
- The vulcanization time is not long enough.
- The vulcanization system needs to be improved.
- Secondary vulcanization can be carried out.