ASTM D2290 Apparent Hoop Tensile Strength of Plastic or Reinforced Plastic Pipe

0 0

ASTM D2290 is a standard that specifies the test method for apparent hoop tensile strength of plastic or reinforced plastic pipe.

What Is ASTM D2290?

ASTM D2290 is a standard test for measuring the apparent tensile strength of plastic pipe test specimens. ASTM D2290 features a fixture that includes a holder with various inserts that are sized to match the range of pipe inside diameters that need to be tested. The inserts transfer the load and allow the pipe to be pulled apart to produce “apparent tensile strength”. It is an apparent tensile strength, rather than a true tensile strength because of a bending moment imposed during the test at the split between two split disk test fixtures. This moment is induced by the change in contour of the ring between the two disk sections as they separate. Apparent tensile strength test results are available at yield, rupture, or both.

What Other Standards Apply to Tensile Testing of Plastic Pipe?

Other tensile test methods used for plastic pipe include ASTM D638, ISO 527-1, ASTM D2105, ISO 6259-1, ISO 6259-2, ISO 6259-3, ISO 8521, and ISO 8513.

Why Perform Tensile Tests on Plastic Pipe?

To characterize the material behavior in different processing states.The process conditions in an extruded pipe can be very different than an injection molded test specimen. To characterize this property, test specimens are taken from the pipe wall in the longitudinal direction of the pipe.

How to Perform ASTM D2290

Pipe test specimens are loaded in a universal test machine through a special self-aligning split disk test fixture which applies tensile stress to the test ring. Model GD2290 self aligning fixture minimizes the effect of this bending moment. The grip inserts are made to match customer pipe sizes.

What Are the Different Test Procedures of ASTM D2290?

Procedure A is used for reinforced thermosetting resin pipe. Procedure B is used for extruded and molded thermoplastic pipe of any size. Procedure C is used for extruded and molded thermoplastic pipe with nominal diameter of 114 mm (4.5 in) and greater.

What Test Machines Are Recommended for Testing Plastic Pipe?

Our universal test machines serve multiple plastic testing applications and are capable of performing all quasi static tension/compression tests, such as tensile, peel, adhesion, and flexural testing. Machine selection is based on the number and type of tests expected to occur in the future. Almost all tests require a uniform constant rate of extension (CRE), or constant velocity control mode with the vast majority occurring between 1 and 500 mm per minute (0.04 to 20 in/min). Each configuration includes a servocontroller, and so perform load and strain control as well. Measurement of force complies with ASTM E4.

ASTM D2290 defines speed of testing as the velocity of the two members (upper and lower fixtures) of the testing machine. The speed of testing is specified as 2.5 mm (0.1 in/min) minimum and 12.7 mm (0.5 in/min) maximum for Procedure A. It is expected to be 12.7 mm (0.5 in/min) for Procedures B and C. The test machine force capacity needs to be sized to test your largest and highest strength pipe to be tested.

What Fixtures Are Recommended for ASTM D2290?

GD2290-908 test fixtures meet ASTM D2290 requirements. The number and size of each GD2290 insert must match the number and sizes of internal pipe diameters to be tested.

Optional digital calipers are matched to the specific sample measurements needed. Data is captured and integrated into the test measurement software.

What Are the ASTM D2290 Test Specimens?

Procedure A reinforced thermosetting resin pipe samples are full-diameter, full-wall thickness rings.

Procedure B thermoplastic pipe samples are full-diameter, full-thickness rings.

Procedure C samples are cut normal to the pipe axis with parallel sides. The width of the specimen is 44 to 50 mm (1.75 to 2.00 in)

Important Considerations When Testing to ASTM D2290

This ASTM test produces consistent and repeatable information with regard to the apparent tensile strength of plastic pipe. ASTM D2290 tests provide data for research and development, engineering design, quality control, and for acceptance or rejection to commercial specifications. Note that plastic behaves in a viscoelastic, or time dependent manner, and so cannot be considered significant for applications that widely differ from the load-time scale of this test. Longer load times will likely result in earlier failures due to creep.