JPH0213830Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a pipe joint. Conventionally, flange joints, threaded joints, and the like have been widely used as pipe joints for gas pipes and water pipes.

However, with flange joints, there are many fastening bolts and nuts around the flange, so for example, in gas pipes or water pipes buried underground, it is necessary to dig deep below the flange, and the bolts and nuts below must be excavated deeply. There are drawbacks such as the fact that nuts are difficult to tighten and workability is poor, and threaded joints also have the drawback that it takes considerable time to turn curved pipes for screwing.

The purpose of this invention is to eliminate the above-mentioned drawbacks.

That is, this invention is a pipe joint that is a threaded type without a flange, but can easily connect even curved pipes, and has high leak-proof performance.

Hereinafter, embodiments of this invention will be described based on the accompanying drawings. As shown in FIG. 1, the pipe joint of this invention has a first pipe 2 with a thread 1 on the outer peripheral surface of the end.
and a conical surface 4 with an inclination angle of approximately 45° on the inside of the end, which has a female thread 3 on the inner peripheral surface of the end to be screwed into the male thread 1, and has a conical surface 4 on the inside of the end.
and a conical surface 7 having a female thread 6 screwed into the male thread 1 of the first tube 2 and in surface contact with the conical surface 4 of the second tube 5 is provided on the outside of the end. A lock nut 8 with a V-shaped cross section for packing is provided at the intersection edge of the conical surface 7 of the lock nut 8 and the female thread 6.
A rubber packing ring 10 is inserted into the ring groove 9, and a lock nut 8 is fastened to connect the two pipes.

The conical surface 4 of the second pipe 5 and the conical surface 7 of the lock nut 8 are tightly pressed against each other when the lock nut 8 is tightened, and their inclination angle is
The angle is preferably 45° to 55°. Further, the lock nut 8 has a polygonal columnar surface on its outer circumferential surface, and is also provided with an anti-slip knurl.

FIG. 2 is a longitudinal sectional side view of the main part showing another embodiment of this invention. In this pipe joint, a conical surface 4 is provided on the outside of the end of the second pipe 5, a ring groove 9 is provided at the intersection edge of the conical surface 4 and the female thread 3, and the conical surface 7 of the lock nut 8 is provided on the inside of the end. It was established in

The pipe joint according to this invention has the structure described above, and when using this pipe joint, the number of turns of both pipes to be connected can be reduced, so even curved pipes can be connected without any effort. It can be easily connected by simply tightening the easy-to-turn locking nut with a spanner, etc., and the internal locking ring provides sufficient leak-tight performance.
It does not take much time to connect, is easy to work with even in narrow spaces, and is strong against loads in the vertical direction.

Furthermore, when you finish tightening the lock nut,
Since the parallel conical surfaces provided on the opposing surfaces of the lock nut and the second pipe are brought into close contact over the entire circumference, a complete seal can be achieved.

Therefore, it can withstand high pressure and is suitable for joints of high-pressure piping, and has the advantage that the lock nut does not loosen due to vibrations and the like, making a double nut unnecessary.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of an essential part showing one embodiment of this invention, and FIG. 2 is a longitudinal sectional side view of an essential part showing another embodiment of this invention. 1... Male thread, 2... First pipe, 3, 6... Female thread, 4, 7... Conical surface, 5... Second pipe, 8... Lock nut, 9... Ring groove, 10... Packing ring.

Claims (1)

[Scope of utility model registration request] a first tube with a thread on the outer circumferential surface of the end; a second tube with a female thread on the inner circumferential surface of the end that screws into the male thread; and a conical surface on the end surface; and the male thread of the first tube. A pipe joint comprising a lock nut having a conical surface that is screwed into the second pipe and in surface contact with a conical surface of a second pipe, and a packing ring groove is provided on the conical surface of the second pipe or the conical surface of the lock nut.