Astm D1414

Rubber bands are also commonly tested under this standard to test their tensile strength and elongation characteristics. This is more likely to occur when combined with excessive compression set. This can sometimes be beneficial to the seal application if the increase is small, as it increases the sealing force and may, at least.

The relationship between hardness and elongation has been mentioned as one example. Without a doubt, the most important of all the measured properties of an O-ring or other elastomeric seal material is compression set. Some advanced calculations including elongation modulus can also be derived from the data. These documents may be obtained from the American Society for Testing and Materials, and the Rubber Manufacturers Association, respectively. The seal material may absorb some of the sealed fluid, resulting in volume swell.

Consider the analogy of an imaginary window of fixed dimensions which can be moved as desired. In reality, compound development involves a series of compromises to achieve the most benefits with the fewest disadvantages.

Automotive Interior Mechanical Testing Guide. Static rubber rings are used for gas sealing and specialized applications including vacuums. You can find photos and detailed technical information about the motorized and non-motorized o-ring fixtures below. Harder rubber materials generally have lower elongation values than softer compounds.

ASTM D - 15 Standard Test Methods for Rubber O-Rings

Top top grip has a counterweight to allow for even loading. Cracking, flaking, general brittleness, and other characteristics can appear in the rubber O-rings when they are exposed to temperature cycles and solar radiation. This is a measure of the ability of the material to recover some portion of its original cross-section thickness after long term compression. There is also another test that does not require the motorized fixture.

Thus, it provides a basis for choosing the most likely candidate materials from a number of compounds. If using the motorized version, the bottom grip and spool is connected to a small variable speed electric motor to enable rotation during the test to minimize stresses. These specimens can be tested as whole rings or as straight, cylindrical. End the test after sample break rupture.

We are confident that we have what you are looking for. Volume change, similar to original physical property changes, is reported as a percent of the original volume, a plus percentage indicating swell and a minus change indicating shrinkage. They are usually assembled with some tension around a shaft or within an o-ring groove to facilitate manufacturing by precluding bulging or bunching during assembly. Have a question about conducting the test for this standard? There are a myriad of similar interrelationships in any elastomer.

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Excessive volume swell, however, can force the seal to extrude and has been known to develop enough pressure to damage mating metal components. The fixture can use interchangeable rollers at different sizes.

Elongation and tensile strength are the two main calculations. Material test reports are not unlike a road map which can guide you in the general direction of your destination. The constant gripping force prevents specimen slippage while under test. If your O-ring specimens fall within the allowed criteria, they can be tested with a static fixture.

O-Ring Material Specsheet Datasheet Test Report Explaination

Give our test engineers a call today for help configuring the best test machine and accessories according to your standard. Test equipment and specific methods of testing are not included here.

There are two different scales for measuring rubber hardness, Type A, and Type D. It should be noted that hardness values are not consistently described in precisely these terms.

Our universal testing systems can easily be used to perform the tests laid out within this standard. These are the tests which are described in this guide, though it is only rarely that all of these will be included in a single material test report. It correlates fairly well with extrusion resistance and, in dynamic applications, with wear resistance as well. Their addresses are listed at the end of this guide. These materials tend to elongate extensively so attention must be made to the total stroke of the tensile tester.

In fact, volume change is sometimes the only test conducted. Planar Biaxial Testing Guide. Weight change after air aging will be either zero no change or a minus quantity weight loss.

ASTM D - 94 Standard Test Methods for Rubber O-Rings

ASTM D1414 Tension Testing and Tension Set of Rubber O-Rings

Compression set should not be confused with resilience or bounce, which is very short term. If a hard material is needed for extrusion resistance, for example, a compromise will be required. Heat is then applied to the solution at a specific rate.

The spools rotate freely on aastm pin extending from the grip. Aastm test methods are also available for both o-ring and straight specimens to make setup time faster and easier. These are stress relaxation tests. In some cases, solidworks for windows 8 64 bit Instron elastomeric rubber grips have been found to work well. Part of the specification includes tension testing for determining the breaking.

Unfortunately, this extra high temperature will sometimes cause changes in the seal material that are different from the changes which occur in actual use. Test reports are used by both the seal manufacturer and the customer for various purposes. The o-ring specimen is to be looped around two cylinders that are sized appropriately for the diameter of the o-ring. Modulus is critical to O-ring sealing performance.

Testing Standards List

Check this box to receive pertinent commercial email from Instron focusing on products, upcoming events, and more! In this case, you atm just use two of the upper grips. Moving the window to provide more illumination in one area however, will reduce the amount of light in another.

O-Ring Material Specsheet Datasheet Test Report Explaination