Determination of the Tensile Properties of Thermoplastics Pipes
Tensile tests on specimens made of thermoplastics pipes are used for the characterization of the material behavior in the processing state.
The ISO 6259 series specifies a procedure for determination of the tensile properties of thermoplastics pipes, including the following: Stress at yield and strain at break.
ISO 6259 objective and requirements Special case welding and connecting seams Standards overview for tensile test on plastics pipes Related products
Purpose of the test
- Tensile tests on specimens are used for the characterization of the material behavior in the processing state.
- Material characteristic values determined under standardized processing conditions on standard test specimens can sometimes deviate considerably from the properties actually present in a pipe. The reason is the processing state, which is completely different in an extruded pipe than in an injection-molded specimen.
- To characterize this property, test specimens are taken from the pipe wall in the longitudinal direction of the pipe. The methodology for sampling and testing is described, among other things, in ISO 6259, Parts 1 through 3. Depending on the pipe material and wall thickness of the pipe, different specimen shapes are used, which are each designed for different types of specimen holders.
- The specimen strain is measured with an optical extensometer, directly on the specimen.
Testing of welded and connecting seams
A special case in tensile testing is the testing of welded and connecting seams. For this purpose, the specimen is taken from the pipe in such a way that the welded or connecting seam is withing the range of the free gauge length of the specimen. Due to the expected inhomogeneity of the strain distribution, a direct extension measurement on the specimen is not necessary in this case. The test result is the tensile strength of the connection point and, if necessary, a comparison with the tensile strength of the pipe material.
Standards for tensile tests on plastic pipes
- ISO 6259-1 Thermoplastics pipes — Determination of tensile properties — Part 1: General test method
- ISO 6259-2 Thermoplastics pipes — Determination of tensile properties — Part 2: Pipes made of PVC-U
- ISO 6259-3 Thermoplastics pipes — Determination of tensile properties — Part 3: Polyolefin pipes
- ISO 8521 Plastics piping systems -- Glass-reinforced thermosetting plastics (GRP) pipes -- Test methods for the determination of the apparent initial circumferential tensile strength
- ISO 8513 Plastics piping systems -- Glass-reinforced thermosetting plastics (GRP) pipes -- Determination of longitudinal tensile properties
- ASTM D2105 Tensile Properties of “Fiberglass” (Glass-Fiber-Reinforced Thermosetting-Resin) Pipe and Tube
- ASTM D2290 Apparent Hoop Tensile Strength of Plastic or Reinforced Plastic Pipe
- EN 1393 Plastics piping systems - Glass-reinforced thermosetting plastics (GRP) pipes - Determination of initial longitudinal tensile properties
- EN 1394 Plastics piping systems - Glass-reinforced thermosetting plastics (GRP) pipes - Determination of the apparent initial circumferential tensile strength
Take advantage of the leading testing software in materials testing
ZwickRoell’s testXpert testing software offers:
- Simple operation: start testing right away and be a testXpert while maintaining maximum safety.
- Reliable and efficient testing: benefit from reliable test results and maximum testing efficiency.
- Flexible integration: testXpert is the optimal solution for all of your applications and processes—simply put, a more effective workflow.
- Future-proof design: testing software for the entire life cycle, ready for your future test tasks!