We are sometimes contacted by businesses who are receiving rubber components from other sources that are failing or underperforming where they were previously acceptable. This could be caused either by a change in the operating conditions or environment, or by a reduced rubber quality due a change in the rubber composition or the manufacturing process used for the part.
It can be difficult to test the quality of rubber on a range of finished parts, or analyse why components begin to fail when historically they have performed well, but there are steps that you can take:
Physical properties such as hardness and tensile strength can be checked if samples of regulation size and shape can be created.
Soak testing can be done to check fluid resistance.
A TGA process can be used to destructively test the components to identify the chemical constituents.
Gas Chromatography can, if needed, provide further insights into the chemical constituents.
These laboratory tests on the quality of rubber are not routinely done unless a comprehensive failure mode analysis is required once a full review of the traceability with the supply chain has been done, along with a series of process checks and validations.
Unfortunately, it is all too easy within a global supply chain to provide documentation that does not reflect reality, and, for safety-critical components, reliable, trustworthy suppliers and high-confidence processes are essential to ensure the product supplied is as it should be, and continues to meet your specification. Rubber moulding compound can be impacted where the supply chain has changed the composition to include higher proportions of lower cost materials, to ostensibly produce the same rubber quality.
Tests that we can offer at Martin’s Rubber include: