JPS5825194B2 - Flexible seismic pipe fitting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flexible earthquake-resistant pipe joint that has an earthquake-resistant function and is excellent in watertightness.

The earthquake resistance function is achieved by allowing movement between the socket and the insertion port within a certain range in the tube axis direction, but reliably preventing the pipe from being pulled out of the socket due to further movement.

Conventionally, as a joint having such a function, for example, Japanese Patent Application Laid-open No. 5
As stated in Japanese Patent No. 0-82623, a protrusion is provided at the tip of the receptacle, and a lock bolt that presses a lock ring that can be engaged with the protrusion against the outer surface of the receptacle is received in a screw hole provided in the receptacle. A device that is screwed onto the outside of the mouth has been proposed.

However, since the threaded hole of the above-mentioned lock bolt penetrates the outer surface of the socket on the back side of the installation position of the sealing member interposed between the socket and the socket, the fluid inside the pipe is leaked from the threaded part of the lock bolt. There is a risk of leakage.

The present invention eliminates such drawbacks, and can eliminate the leakage of fluid inside the pipe unlike those using the conventional lock bolt, and is extremely powerful and capable of removing the insertion port without using a lock bolt. It is an object of the present invention to provide a flexible earthquake-resistant pipe joint that can reliably prevent earthquakes and which can easily perform joint joining work.

The present invention provides an annular engagement protrusion on the inner peripheral surface of the socket adjacent to the back side of the tapered surface formed on the inner peripheral surface of the opening end of the socket, and provides a tapered surface at the tip of the socket. A lock ring is provided that is fitted into an annular groove provided on a nearby outer circumferential surface by a diameter-reducing biasing force and that can be engaged with the engagement protrusion in the fitted state, and the lock ring is provided on the inner circumference of the socket on the back side of the engagement protrusion. The surface has enough space to allow movement and deflection of the receptacle into which the lock ring is fitted, and the inner surface of the tube that continues to the step surface at the far end of the inner circumferential surface of the receptacle,
An annular recess into which the tip end of the insertion port on the distal side of the annular groove can be fitted is provided, and a backup ring that engages with the engagement protrusion and a sealing material that is crimped onto the back amplifier ring are inserted into the socket in this order. By inserting from the open end between the inner peripheral surface of the receptacle and the outer peripheral surface of the receptacle and pressing and fixing with a press ring tightened with a bolt and nut, a distance that allows the receptacle to move is created between the engaging protrusion and the lock ring. This achieves the intended purpose by allowing the insertion port to flex with respect to the receptacle.

゛An embodiment of the present invention will be described below based on the drawings.

1 is a socket, 2 is a socket, and the inner surface of the socket 1 is formed with a tapered surface 4 on which a sealing material 3 is installed at the open end, and an annular engagement is formed on the inner circumferential surface 16 of the socket adjacent to the back side. A mating protrusion 5 is formed.

Reference numeral 6 denotes a split lock ring that can be engaged with the engaging protrusion 5, and an annular groove 7 formed on the outer circumferential surface near the tip of the socket 2.
It is fitted with a force for reducing the diameter.

This lock ring 6 is made of, for example, ductile cast iron.

Note that the outer surface of the tip 8 of the socket 2 is formed into a tapered surface for fitting the lock ring 6.

Reference numeral 9 denotes a back end step surface formed at the back end of the socket 1 where the socket inner circumferential surface 16 connects to the pipe inner surface 17;
An annular recess 10 is provided on the inner surface 17 of the tube following the annular groove 7 into which the insertion opening tip 8 can be fitted.

On the other hand, the sealing material 3 is made of a rubber ring, and between the sealing material 3 and the engagement protrusion 5, there is a hole on the back side of the socket that engages with the tapered side surface of the engagement protrusion 5. A backup ring 11 having an engagement tapered surface with a small diameter and pressed into contact with the protrusion 5
is located.

The back amp ring 11 is formed as a single piece and is made of hemp, hard rubber, steel, or the like.

Reference numeral 12 denotes a press ring that comes into contact with the sealing material 3, and is attached by a bolt nut 14 inserted through the hole 13a of the flange portion 13 of the socket 1 and the hole 12a of the press ring 12. By tightening the bolt nut 14, the sealing material is removed. A pressing force is applied to the socket 3 to ensure watertightness between the socket 1 and the socket 2.

According to such a configuration, the engagement protrusion 5 and the step surface 9 at the back end of the socket
The lock ring 6 can be moved between the two, and relative movement of the socket 1 and the socket 2 in the tube axis direction is allowed within this range.

Further, the contact between the engaging protrusion 5 and the lock ring 6 reliably prevents the lock ring from being pulled out, thus providing an earthquake-resistant function.

Next, the joining operation will be explained.

First, the press ring 12, sealing material 3, and backup ring 11 are placed in the socket 2, and the lock ring 6 is placed in contact with the step surface 9 at the far end of the socket 1 as shown by the chain line in the figure. is inserted until its tip 8 fits into the annular recess 10.

As a result, the lock ring 6 remains in contact with the step surface 9 at the rear end and is pushed and expanded by the tapered surface of the tip 8 of the insertion port 2 to fit onto the tip 8, and when it corresponds to the annular groove 7, It is easily fitted into the annular groove 7 by the diameter reduction biasing force.

Note that if a flexible positioning member 15 is placed between the lock ring 6 and the inner surface of the socket 1 as shown by the chain line in the figure, the lock ring 6 will not become eccentric, and the insertion of the socket 2 will be prevented. can be carried out smoothly.

After this, the sealing material 3, press ring 12, etc. are installed from the outer surface, and the joint joining is thus completed without the need for operations from the inner surface.

Therefore, it is particularly suitable for small and medium diameter pipes.

As explained above, this invention prevents removal by engaging the locking ring at the tip of the socket with the engagement protrusion protruding from the inner surface of the socket, so it uses a conventional lock bolt. Unlike conventional pipe fittings, it has a function to prevent pipe fittings from being pulled out, while also providing sufficient watertightness, and since the fitting will bend relative to the socket due to ground subsidence, etc., damage to the pipe joint will be avoided within a specified range. can be avoided.

In addition, the lock ring to be attached to the socket is split into one piece and placed on the stepped surface at the far end of the socket so that when the socket is inserted, it fits into the annular groove of the socket, so that it can be inserted from the inside of the tube. Joints can be easily joined without performing any operations.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional side view showing an embodiment of the present invention. 1... socket, 2... insertion, 3...
...Sealing material, 5...Engaging protrusion, 6...
・Lock ring, 7... Annular groove, 9...
・Rear end step surface, 10... Annular recess, 11...
...Backup ring, 12...Press ring, 14
... Bolt nut, 16 ... Inner peripheral surface of socket, 17 ... Inner surface of tube

Claims (1)

[Claims] 1. An annular engagement protrusion is provided on the inner circumferential surface of the socket adjacent to the back side of the tapered surface formed on the inner peripheral surface of the socket opening end, and a tapered surface is provided at the tip of the socket, and the outer periphery near the tip of the socket is A lock ring is provided that is fitted into an annular groove provided on the surface by a diameter-reducing biasing force and can be engaged with the engagement protrusion in the fitted state, and is provided on the inner circumferential surface of the socket on the back side of the engagement protrusion. , the socket in which the lock ring is fitted has enough space to allow movement and deflection, and a tip of the socket on the distal side of the annular groove is provided on the inner surface of the tube following the stepped surface at the far end of the inner circumferential surface of the socket. A backup ring that engages with the engaging protrusion and a sealing material that is crimped onto the backup ring are inserted in this order from the opening end of the socket to the inner peripheral surface of the socket and the outer periphery of the socket. A flexible earthquake-resistant pipe joint characterized by being inserted between surfaces and compressed and fixed by a press ring that is tightened with bolts and nuts.