We are working closely with a leading European O-ring laboratory and testing facility. With this partnership, we can offer you an even more complete range of services.
Tests we can perform:
Identity tests are understood as tests that allow finding conformities of a test lot with the reference values from the sampling or from previous deliveries. They include simple testing methods that can be supplemented with more complex and more significant ones if required.
Hardness tests are understood as the metrological recordings of hardness on rubber test sheets or finished parts. This hardness is determined by means of a standardized identifier. Hardness tests are probably the most applied and most common test method in the elastomer industry.
Elastomers are not ideal elastic materials. For example, if a seal is deformed for a longer period, the seal will not return to its original shape after removing the deformation. If this deformation takes place at high temperatures, this effect is especially evident, even if the maximum temperature of the seal has not been exceeded.
At low temperatures, rubber materials constantly lose their elastic recovery force, which means that they can only bridge the gap size to a limited extent and can significantly slow down their reset speed.
A Tensiontest (TS test) such as a compression test (CS test) is a possibility to obtain information about the relaxation behavior and the crosslinking state of a sample due to its resilience behavior after a controlled temperature load. In special cases of application and with special sealing geometries, it is a useful addition to the compression test.
During a tensile test, standardized samples (in most cases special tensile test samples) as well as finished parts (e.g. O-rings) are clamped in a tensile test machine and stretched at a constant speed until they tear. During this process, the progress of the required strength and elongation is recorded and a tensile diagram is compiled.
Immersion tests are performed to ensure the functional behavior of rubber materials or elastomer seals relative to different materials. In the course of this, the following information is provided:
• Impact due to swelling (increase or decrease in volume)
• Change in hardness (embrittlement or softening)
• Change in the network structure of the material as a result of a chemical attack.
During heat aging, a standardized sample is exposed to hot ambient air over a predefined constant temperature. This process takes place with several samples in a type of circulation air oven with fresh air supply or in cell ovens separated into samples. The assessment of materials that age in hot air is made by comparing important physical values (e.g., hardness, tensile strength, elongation at break and the like) before and after aging.
Under normal environmental ozone concentrations, elastomer materials may form deep cracks which usually lead to a failure of a component. But the following conditions are required:
• A highly unsaturated polymer, e.g. NBR, NR or SBR
• A deformation > 3-5%
• An admission of ozoniferous air (an unbraked air exchange at the seal)
In practice, this occurs particularly at pre-installed NBR-seals which are exposed to their environment. In contrast, this does normally not occur at installed seals.
With the new edition of the standard ISO 3601-5 in April 2015, it has been achieved to define a standard for material formulations and requirements of finished parts on an international level.
As an accredited laboratory, our results are viewed as impartial, which has significant benefits for the customer and the recipient of the test reports, because these results are credible. Especially in the automotive industry, this is becoming more and more in demand. That is why the O-ring testing laboratory performs many tests according to different OEM specifications.
We regularly carry out resistance tests in which the resistance to various oils is tested. Hydraulic fluids have been tested according to ISO 6072. Of course, we also test according to your standards or your elastomer material. In the context of car specifications, we also regularly perform tests with various engine- and transmission oils.
Especially for tests in refrigerants, such as HFO-1234yf or R1234yf or R134a, we have a special in-house filling system to create a vacuum in the autoclaves before filling. We also carry out regular resistance tests on carbon dioxide, CO2. On request, we also carry out tests in other refrigerants.
We perform tests in water or steam, in coolant mixtures and other aqueous mixtures until over 200°C.
The low-temperature behavior of elastomers could be measured by a lot of different test methods that are not comparable. Therefore it is important, to know these methods. However, it could be even more confusing, if just a low-temperature limit is given without any relation to a test method. We recommend applying either the TR10-method or compression set at low temperatures or DSC-method.
Send us an email with your specifications and we'll get you the right certifications or test result straight out of our accredited Laboratorium.