Product test standards such as ISO 15630-1 for rebar frequently make reference to ISO 6892-1 for tensile testing requirements. When tensile testing steel products like reinforcement bar (rebar), wire rod, plate or pipe, it is often difficult to produce test specimens that are perfectly straight, flat, or smooth. Small diameter rebar and wire rod specimens are cut from product that has been uncoiled and straightened. Pipe specimens are frequently cut from a finished pipe section and require flattening. These types of imperfect specimens pose gripping challenges for test equipment.
When testing these irregular specimens, it may be necessary for the test machine grips to supply high initial clamping force to help straighten and auto-center the sample during clamping. For these requirements we recommend our new DuraSync™ dual side-acting hydraulic grips as they can produce very large initial clamping forces without generating large compressive forces on the specimen. The DuraSync grips mounted in the convenient test space of a KPX load frame provide a very ergonomic test environment for the operator. If a more automated solution is desired, the fully automatic MFX 500 Extensometer can also be added for measurement of axial strain.
Bluehill® 3 testing software and its metals test suite provide a simple user interface and powerful control parameters to meet the demands of ISO 6892-1 and other related test standards. The software is also fully integrated with the MFX 500 automatic extensometer and provides a user-friendly interface for setting the desired instrument settings such as gauge length and arm location.
We recommed reading and reviewing ISO 6892-1 in order to fully understand the test set up, procedures and results requirements.