GAS - RC -RP -BSPT taps and dies

The GAS thread derives from the Whitworth thread (created in 1833 and still in use in the mechanical field) and is characterized by a very fine pitch, a 55° flank angle, and a rounding of the thread at both the crest and the root. The GAS thread designation is conventional: it refers to the internal diameter of the pipe expressed in inches. GAS threads are divided into cylindrical GAS threads and tapered GAS threads. With the cylindrical GAS thread, also called parallel thread (UNI ISO 228-1 Pipe threads for non-sealing coupling on the thread), the coupling occurs via a cylindrical screw and nut, but does not guarantee a watertight connection. The hermetic coupling can only be achieved with the use of gaskets. Parallel threads can be designated with the letter G, followed by the value of the internal diameter in inches. For example, to indicate a cylindrical GAS thread on a pipe with an internal diameter of one inch, the code G 1" is used. The tapered GAS thread (UNI EN 10226 Pipe threads for thread-tight couplings) ensures a watertight connection by mating a tapered screw with a tapered or cylindrical female thread. Watertight pipe threads are designated with the letter R (tapered external thread). For example, to indicate a tapered GAS thread on a pipe with an internal diameter of one inch, the code R 1" is used. To further distinguish between internal threads, the letters p and c can be added as follows:

• Rp 1" for thread with a cylindrical female thread (UNI EN 10226-1);

• Rc 1" for thread with a tapered female thread (UNI EN 10226-2).