Views:23 Author:Site Editor Publish Time: 2019-08-20 Origin:Site
Silicone Injection Molded Parts Dimensional Tolerances
Thermoset molded elastomers do not lend themselves well to the same level of tolerancing. Elastomers are influenced by many variables: temperature, cure time, mold tolerance, mold registration, compound variation, and shrinkage are just some of the factors all molders encounter.
The Association for Rubber Products Manufacturers (ARPM) has updated tolerance tables with ranges to provide communication between user and provider across a wide range of industries, from precision aerospace electronic components to open-tolerance products for consumer goods. These tolerance designations relate to the variability inherent in processing molded rubber parts and are referred to as ARPM “A2” Precision and ARPM “A3” Commercial dimensional tolerance designations.
To achieve different tolerance level, the cost is different. Normally, higher pricision, the cost is higher.
Silicon rubber molder need to prepares to meet customer requirements. That includes preparations for tooling, extra features, cavity finishes, and cavity flow provisions.
Temperature control and timing of molding cycles are also the cost of the molded parts.
And different types of rubber materails,especially its durometer hardness, will determine if the part will experience substantial size change during its cooldown.
Different types of moldings, the tolerance is different. For Liquid Silicone Rubber Injection Molding, the tolerance is precision than compression molding.
Some rules need to follow when applying tolerance:
Fixed dimension tolerances apply individually to each fixed dimension by its own size.
Closure dimension tolerances are determined by the largest closure dimension and this single tolersnce is sued for all other closere dimensions.
Fixed and closure dimensions can be split between tables and do not necessarily go together.
Xiamen Better Silicone Rubber Co,.Ltd is specialized in manufacturing high precision silicone rubber parts, Liquid Silicone Rubber (LSR) parts and plastic components in different areas.
We have a lot of test equipment that can make sure all the products can achieve customers' requirement, and can control the dimension according to customers' tolerance demands.