| 摘要 |
<p>An economical thread joint structure is provided for preventing a turbulent flow of fluid passing through the inside. In the pipe thread joint structure, female threads (11, 12) are formed in the inner circumferential surface of a coupling (10) narrowed from both ends thereof toward the center thereof. Male threads (21, 31) fit to the female threads (11, 12) of the coupling (10) are formed at end portions of first and second pipes (20, 30) respectively. The first and second pipes (20, 30) are inserted to left and right sides of the coupling (10), and tightened up to and fitted into the coupling (10) respectively. The fitting distance of the first pipe (20) into the coupling (10) is made 0.050-0.150 inches longer than the fitting distance of the second pipe (30) into the coupling (10) when the outer diameter of the pipes is not larger than 9 inches. The former fitting distance is made 0.150-0.250 inches longer than the latter fitting distance when the outer diameter is larger than 9 inches. <IMAGE></p> |
