ISO 8496 pdf download

ISO 8496 pdf download Metallic materials — Tube — Ring tensile test
1 Scope
This International Standard specifies a method for a ring tensile test of tubes to reveal surface and internal defects by subjecting the test piece to strain until fracture occurs. This test may also be used to assess the ductility of tubes. The ring tensile test is applicable to tubes having an outside diameter exceeding 150 mm and a wall thickness no greater than 40 mm. The inside diameter shall be greater than 100 mm.
2 Principle
Subjecting a ring cut from the end of a tube to strain in the circumferential direction until fracture occurs.
3 Apparatus
Use two circular pins, of equal diameter with parallel axes, and movable in relation to each other while still remaining parallel. In principle, the diameter of the pins shall be the minimum permissible from strength considerations but, provided that the inside diameter of the tube allows, should be at least 3 times the wall thickness of the tube to be tested (see Figure 1).
4 Test piece
4.1The test piece shall be a ring cut from the tube with the end faces perpendicular to the axis.
4.2 The length of the test piece (width of the ring) shall be approximately 15 mm. If the thicknessexceeds 15 mm, the length of the test piece may be equal to the thickness.
4.3The ends ofthe test piece shall be free from burrs. The edges may be rounded by filing or chamferedby other methods.
NOTENon-rounded or non-chamfered edges are permissible,ifthe test result meets the test requirements.
5 Procedure
In general, the test shall be carried out at ambient temperature within the limits of 10 °C to 35 °.5.1The test carried out under controlled conditions shall be made at a temperature of 23 °C + 5 .
5.2Place the ring cut from the tube over the pins. Subject the ring to strain by moving the pins awayfrom each other at a specified rate until it fractures.
In cases of dispute, the rate shall not exceed 5 mm/s.
5.3Interpretation ofthe ring tensile test shall be carried out in accordance with the requirements oftherelevant product standard. When these requirements are not specified, the test piece shall be consideredto have passed the test if the expected fracture behaviour was obtained and no other cracks are visiblewithout the use of magnifying aids.
6 Test report
A test report shall be provided when so specified in the relevant product standard. In this case, the testreport shall include at least the following information:
a) a reference to this International Standard,i.e.ISO 8496:
b) identification of the test piece;
dimensions ofthe test piece;
d) result ofthe test.