Tube-Flattening Test to ISO 8492, DIN 50136, API 5 L
The tube-flattening test to ISO 8492 and DIN 50136 is a test method used in materials testing for evaluating the ductility of weld seams as well as for detecting defective weld seams on metal tubes. The tube-flattening test is assigned to the compression test category.
Testing of steel tubes such as the ring tensile test is also described in Annex 2 of ASTM A370.
The following content explains the key aspects. For standard-compliant testing to ISO 8492 and DIN 50136, it is essential to purchase the complete standard.
How is the tube-flattening test to ISO 8492 and DIN 50136 performed?
For the tube-flattening test, a ring is taken from a tube. The ring is compressed to a defined distance between two compression platens using a testing machine. The position of the weld seam is alternately at a 90° angle or parallel to the compression platens so that the weld seam is subjected to tensile load once on the inside of the tube and once on the outside of the tube.
Cracks on the inner or outer surface of the tube ring indicate defects in the material or the weld seam. Additional test results such as the force curve or displacement curve can be evaluated using the testXpert testing software.
Frequently asked questions
The tube-flattening materials testing method is used to evaluate the ductility of weld seams and to identify defective weld seams on metal tubes. The tube-flattening test is part of the compression test category and is described in standards ISO 8492, DIN 50136 and in Annex 2 ASTM A370.