ASTM D2412 Plastic Pipe Deflection Testing

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ASTM D2412 Plastic Pipe Deflection Testing

ASTM D2412 is a standard test method for measuring the deflection of plastic pipe specimens, which are often used in commercial and residential plumbing. The ASTM D2412 plastic pipe deflection testing procedure measures the change in length of a specimen of pipe under load, which provides an indication of the strength of the material.

What Is ASTM D2412?

ASTM D2412 measures pipe stiffness, stiffness factor, and load deflection characteristics of thermoplastic resin pipe, reinforced thermosetting resin pipe (RTRP), and reinforced polymer mortar pipe (RPMP).

What Is the Purpose of ASTM D2412?

Testing the external loading of plastic pipe is important for these reasons:

  1. To determine the stiffness of the pipe. This is a function of the pipe dimensions and the physical properties of the material of which the pipe is made.
  2. To determine load-deflection characteristics and pipe stiffness which may be used for engineering designs.
  3. To compare the performance characteristics of various plastic pipe.
  4. To understand dimensional and deflection interrelationships and properties of plastic pipe and conduits.
  5. To measure the deflection and load-resistance at any of several significant events if they occur during the test.

How to Perform a Load Deflection Test on Plastic Pipes per ASTM D2412

A short length of pipe is loaded between two rigid parallel flat plates at a controlled test speed. Test sample diameter deflections are measured during loading by continuously recording plate or cross head travel via the position encoder. Load-deflection data of the pipe diameter are captured, stored and reported.

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). The measurement of force complies with the accuracy requirements of ASTM E4. ASTM D2412 requires relatively slow test speeds of 12.5 mm/min (0.50 in/min).

Our test machines meet or exceed the ASTM D2412 requirements.

ASTM D2412 Test Specimens

  • If the test sample is a thermoplastic pipe, then the length of the test specimen should be 150 mm (6 in).
  • For reinforced thermosetting resin pipe, the minimum test specimen length is three times the nominal pipe diameter or 300 mm (12.0 in), whichever is smaller.
  • For pipe larger than 1524 mm (60 in) in diameter, the minimum specimen length is supposed to be 20% of the nominal diameter adjusted to the nearest 25.4 mm (1 in).
  • Certain RTRP pipes exhibit surface irregularity because the production process is based on controlling the inside diameter.
  • Must be uniformly loaded along its entire bearing surface.

What Test Fixtures Are Recommended for ASTM D2412?

Our G36 series compression loading plates are ideal for ASTM D2412. Load is applied to the specimen through two parallel steel bearing plates that are flat and smooth. No bending or deformation occurs during the test. The plate length is equal or greater than the specimen length and the plate width is more than the pipe contact width at maximum pipe deflection plus 6.0 in. (150 mm).

The E3540 Deflectometer or LVDT position indicator is used to measure the deformation change in inside diameter, or deformation parallel to the direction of loading. The deflectometer is accurate to better than 0.010 in. (0.25 mm).

Our TestVideo software module provides high resolution video capture of the test. Playback is time synchronized with load data. Contact us for more information.