Red Seal Steamfitter/Pipefitter Practice Exam

What is the main use of pipe joint compound?

1. To clean the pipes

2. To seal threads of pipe joints

3. To enhance the raw material of pipes

4. To reduce friction within the pipes

The correct answer is: To seal threads of pipe joints

The main use of pipe joint compound is to seal the threads of pipe joints. This compound, often referred to as thread sealant or pipe dope, plays a critical role in ensuring that connections between pipes are watertight and can withstand pressure without leaking. When applied to the threaded areas of pipes, it creates a barrier that fills in any gaps or imperfections in the threads, preventing leakage of fluids or gases. Using a pipe joint compound is essential for maintaining system integrity, particularly in plumbing and HVAC applications, where leaks can lead to significant damage or loss of materials. Unlike cleaning agents or friction reducers, which serve different purposes within pipe systems, the joint compound directly addresses the integrity of the connections. Its effective sealing properties help prevent potential failures in the system, ensuring that it operates safely and efficiently.