What Does Endurance Limit Mean?
The endurance limit (also known as the fatigue limit) of a material represents the point in a material's test in which the test specimen completes all the requirements of the test without any occurrence of failure. The number of cycles in the test has no bearing on the endurance limit; the only germane fact is a material’s survival of the test without failure. For example: One cycle might involve bending a piece of steel back and forth repeatedly.
Trenchlesspedia Explains Endurance Limit
Endurance tests are part of the design and testing process for any piece of trenchless equipment. The successful use of this equipment requires that engineers and operators know how far they can push their equipment before it breaks. Almost all material and equipment, whether a drill bit, pipe, auger horizontal drilling rig or any other piece of equipment that ends, flexes, rotates, or otherwise moves undergoes some form of endurance testing.
Pipes, pipe liners epoxies, concrete, stainless steel and iron used in trenchless technology also undergo testing by organizations such as the American Society for Testing Material (ASTM) the American Society of Mechanical Engineers (ASME), the Society of Automotive Engineers (SAE) or the Canadian Standards Association (CSA). The limits of the endurance test, as determined by equipment and materials testing organizations, are the endurance limit for the equipment or material that doesn't fail. When you see these limits defined on the manufacturer's identification plate, you know that the equipment will last at least that long without failing.