Scope:

ASTM D6396 test method specifies the processes for assembling, evaluating, and testing pipe thread sealants, as well as determining the thread sealant’s main characteristic features. In usage, thread sealants should be able to withstand shocks and vibrations while maintaining secure seals.

Test Procedure:

In ASTM D6396 testing, the sealants are applied after the specimens are removed from the temperature chamber. They are cured for the required amount of time after which the removal torques are computed. This technique is required for the cure speed v/s temperature computation (30 s of withdrawal from the temperature chamber), primer cure (using primer), and heat aging.

The torque removal is determined in the hot strength test (30 s of removal from the temperature chamber). In the solvent resistance test, assemblies are placed in the solvents and experimented for a total of 30 days. The torque removal and assembly are determined by the pipe tee torque test block setup. In steam resistance, the tee is filled with adequate water to the point where all the joints can be reached through the aperture. During test assemblies, the same amount of water is added. As a control group, one assembly is used without any water. After curation, a third sealant-coated piece is installed by recording the weight of each assembly. The assemblies are placed in a pressurized pot with a temperature chamber. These are removed at a one-week interval to record the weight and also for noting the weight reductions for a maximum of six weeks. In the high-pressure test, the couplings, caps, and nipples are rinsed with isopropyl alcohol. Afterwards, the test samples are dried and checked for fault or separation by applying the primer and sealants. The caps and couplings are installed with a 74 ft-lbs torque wrench. In the instant seal test, each assembly is checked for sealability using ASTM D1599 at 10,000 psi after curation. The pipe tee is attached to the assembly and then immersed in the water after applying the sealant. Air bubbles are removed during the immersion process and then pressurized for 5 min at 80 to 100 psi (0.56 to 0.5 MPa). The same process is followed for the sealability test except for the pressuring time and also the leak paths are checked during the test.

Video 01: Weld-on pipe thread sealants

Sample size: 

To test in accordance with ASTM D6396, the size of the specimens should be as follows: 

Malleable Iron Pipe Tees, 3⁄8 in. (10 mm), Forged Steel Pipe Plugs, 3⁄8 in. (10 mm), Stainless Steel Pipe Tees, 3⁄8 in. (10 mm), 304SS, Stainless Steel Pipe Plugs, 3⁄8 in. (10 mm), 304SS, Brass Pipe Tees, 3⁄8 in. (10 mm), Brass Pipe Plugs, 3⁄8 in. (10 mm), Malleable Iron Pipe Tees, 1⁄2 in. (13 mm), Class 300, Forged Steel Pipe Plugs, 1⁄2 in. (13 mm), Hex Reducing Coupling, 1⁄2 in. (13 mm) FNPT by 1⁄8 in. (3 mm) FNPT, 316 stainless steel, Cap, 1⁄2 in. (13 mm) pipe cap and Hex Long Nipple, 316 SS.

Data: 

ASTM D6396, data should be in inch-pound units to be considered standard. This standard does not include any other units of measurement.

Conclusion:

This ASTM D6396 test method specifies the processes for assembling, evaluating, and testing pipe thread sealants, as well as determining the thread sealant’s main characteristic features.