How to Seal the Threads on a PVC Pipe

PVC (Polyvinyl Chloride) piping requires the same type of maintenance and reinforcement as galvanized piping. Sealing PVC pipe threads prevents leaks, friction and contamination that could result in an unstable system. TFE piping tape is normally a popular option for pipe sealant, but can lead to over-tightening on plastic applications. An anaerobic sealant, also called dope, is recommended for PVC and provides a more durable bond between the male and female pipe threads.

Things You'll Need

• Pipe dope
• Rag

Instructions

1. Purchase a pipe dope specifically rated for plastic applications. This must clearly be indicated on the tube for the sealant to work efficiently.

2. Clean both the male and female pipe threads of any oil, grease or dirt. Pipe sealant is most effective when there is no air trapped in between the threads.

3. Squeeze the dope around the first two male threads using a full 360-degree application. Make sure that the sealant fully adheres to the threads and does not overhang or drip from the pipe.

4. Insert the female pipe threads over the coated male end. Use a dry rag to remove the excess dope once the piping is assembled.

References

• Powell Fabrication: Pipe Joint Thread Sealant Instructions
• The Stucco Company: Pipe Dope on Plastic