Dimensional Tolerances for Rubber Molded Components
Unlike rigid machined materials, thermoset moulded elastomers do not lend themselves well to the same level of tolerancing. Being thermally moulded, elastomers are subject to many variables. Temperature, cure time, mould tolerance, mould registration, compound variation, and shrinkage are almost need to be considered by mould makers.
Need to remind when design components!
Peoples are always ignored or forget the characteristics of elastomers is soft and more sensitive against tolerances than plastic parts. If design tolerances are harsh require as high precision as a plastic part, the outcome is always a lot of uncertainty there.
*Rubber is formed a listed of ingredient and there is a chemical reaction when curing and post-curing.
Tolerances for rubber mould parts
Unlike rigid machined materials, thermoset moulded elastomers do not lend themselves well to the same level of tolerancing. Being thermally moulded, elastomers are subject to many variables. Temperature, cure time, mould tolerance, mould registration, compound variation, and shrinkage are almost need to be considered by mould makers.
Need to remind when design components!
Peoples are always ignored or forget the characteristics of elastomers is soft and more sensitive against tolerances than plastic parts. If design tolerances are harsh require as high precision as a plastic part, the outcome is always a lot of uncertainty there.
*Rubber is formed a listed of ingredient and there is a chemical reaction when curing and post-curing.
Rubber mould parts are tolerated according to DIN ISO 3302.
A distinction is made between 4 tolerance classes from Class M1 = fine to Class M4 = coarse. Depending on the press direction of the mould, the norm, in addition, distinguishes between dimensions bound to the mould (F) and the two-component adhesion system measurements bound to the mould closure (C).
Depending on the process, the dimensions bound to the mould closure (C) are tolerated more largely than the dimensions bound to the mould (F).
