What is the main function of tapered threads in fittings?

The main function of tapered threads in fittings is to create a seal as they tighten. Tapered threads are designed so that the outer diameter of the threads decreases along the length of the fitting. When two fittings with tapered threads are joined, the tightening action compresses the threads together, which causes the material at the point of contact to deform slightly. This deformation helps to fill any gaps between the threads, creating a tight seal that prevents leakage of fluids.

This sealing capability is crucial for applications where the integrity of the connection must be maintained under pressure or where fluid containment is critical. Tapered threads are commonly used in plumbing, gas lines, and hydraulic systems, where a reliable and leak-proof connection is essential for safe and efficient operation.