JP5322869B2 - Pull-out prevention fitting - Google Patents

Description

  The present invention relates to an escape prevention pipe joint, and relates to a pipe joint structure used in a well or the like.

  Conventionally, as a seismic joint, for example, an insertion port of the other tube is inserted into the receiving port of one tube, a pair of tubes are connected to each other, and the inner peripheral surface of the receiving port and the outer periphery of the insertion port are formed by rubber rings mounted in the receiving port. Stops water between the pipes, and prevents the pipes from coming apart by locking the engagement part formed in the outer peripheral surface of the insertion slot in the axial direction of the pipe slot with a split ring mounted in the receiving port. There is something.

  In this configuration, a lock ring centering rubber is interposed between the inner peripheral surface of the receiving port and the lock ring, and the lock ring centering rubber centers the lock ring with respect to the tube axis. When the insertion port is inserted into the receiving port, the tip of the insertion port is inserted into the lock ring, the diameter of the lock ring is increased with the insertion of the insertion port, and the lock ring is attached to the outer peripheral surface of the insertion port. When the diameter of the lock ring is increased, the lock ring centering rubber is pressed in the tube diameter direction, and the lock ring centering rubber is compressed to secure a diameter for expanding the lock ring.

  Alternatively, as described in Patent Document 1, a rubber ring is inserted between the outer peripheral surface of the insertion port and the inner peripheral surface of the receiving port, and the retaining push ring disposed in front of the opening of the receiving port is received by the bolt nut. In some cases, the rubber ring is pressed with a retaining push ring so that the rubber ring is pressed against the outer peripheral surface of the insertion port and the inner peripheral surface of the receiving port.

Japanese Utility Model Publication No. 6-30594

  In the conventional configuration described above, each component of the insertion port, lock ring, lock ring centering rubber, and receiving port exists sequentially in the tube diameter direction as the joint structure of the tube, and the outer diameter size of the receiving port is each configuration. It is determined in consideration of the wall thickness dimension of the element in the radial direction and the diameter of the lock ring.

  By the way, when piping a pipe vertically in a well or the like, a vertical hole for piping the pipe is drilled until reaching a predetermined depth, and then the vertical hole is piped. When excavating a vertical hole, in order to suppress the collapse of the inner wall of the hole, it is dug while injecting water bentonite into the soil around the vertical hole. Then, the pipe is suspended in the vertical hole that has been dug, and the pipes are piped while sequentially adding the pipes. After the piping is finished, gravel is filled in the gap between the inner wall surface of the vertical hole and the outer periphery of the pipe.

  The inner diameter of the vertical hole needs to be larger than the outer diameter of the receiving port. For example, when a pipe having a nominal diameter of 300 mm is piped, it is necessary to excavate a vertical hole having a diameter of 450 mm. In addition, when a new pipe is installed in an old well where water can no longer be pumped, a pipe having an outer diameter of about 100 mm smaller than the inner diameter of the existing pipe is used as the new pipe.

  However, a ductile cast iron pipe needs to be provided with a receiving port in the joint structure of the tube, and the outer diameter of the tube is increased at the receiving port, and the space between the inner wall surface of the vertical hole and the outer peripheral surface of the receiving port is narrowed. For this reason, the gravel filled in the gap between the inner wall surface of the vertical hole and the outer peripheral surface of the pipe is clogged around the receiving port, which becomes a factor that hinders the gravel filling operation. Increasing the diameter of the vertical hole causes an increase in excavation costs and an increase in consumption materials such as gravel, which increases costs.

  By the way, in the case of piping in a vertical hole, if a lower pipe falls off at a pipe joint, it is difficult to pick up the dropped pipe. For this reason, it is necessary to fully prevent the lock ring from coming off and to prevent it from coming off, and it is necessary to securely attach the lock ring when connecting the receiving port and the insertion port.

  The present invention solves the above-mentioned problems, holds the lock ring in an appropriate position when connecting the receiving port and the inserting port, ensures that the lock ring is mounted, and reduces the outer diameter of the receiving port to reduce gravel. It is an object of the present invention to provide a slip-off prevention pipe joint that can smoothly fill the filler.

  In order to solve the above-mentioned problem, the escape prevention pipe joint of the present invention includes a receiving port that forms an end of one tube, an inserting port that forms an end of the other tube, and is inserted into the receiving port. An insertion recess formed in the outer peripheral surface, a lock ring that can be mounted on the insertion recess and expandable / reducing, and a reception recess that is a space formed in the inner peripheral surface of the reception port and accommodates the lock ring in an expandable / contractable manner. A pipe joint having a pipe axial direction support member for receiving the lock ring in the pipe axial direction and a pipe radial direction support member for receiving the lock ring in the pipe radial direction and holding the lock ring in a predetermined position on the back side of the pipe; The radial support member is displaceable over a locking position for locking the lock ring in the tube radial direction and a retracted position for retracting from the lock ring in the tube radial direction to the tube axis direction.

  With the above-described configuration, the lock ring accommodated in the recess of the receiving port is in an unloaded and relaxed free state when the insertion port is not inserted into the receiving port, and the tube axis direction support member has the lock ring. While receiving in the axial direction of the tube, the tube radial support member locks the lock ring in the tube radial direction and holds it in place. In this state, the lock ring is positioned so as to be substantially concentric with the tube axis.

  At the time of connection, the insertion port is inserted into the receiving port, and the insertion port is pushed toward the back end of the receiving port while inserting the distal end of the insertion port into the lock ring. At this time, since the lock ring is centered with respect to the tube axis by the tube radial direction support member, the lock ring is surely concentrically opposed to the insertion opening, and the lock ring is twisted. It fits in the mouth normally without accompanying.

  With the tube axis direction support member supporting the lock ring against the pressure of the insertion port, the lock ring expands when the tip of the insertion port enters the lock ring, and passage is allowed by the expansion of the lock ring. The insertion port enters the back end side of the receiving port, and the lock ring is attached to the insertion port recess. When the diameter of the lock ring is increased, the tube diameter direction supporting member is pressed by the lock ring and displaced from the locking position to the retracted position, and is retracted from the lock ring in the tube diameter direction toward the tube axis.

  Therefore, when the diameter of the lock ring is increased, the inside of the receiving recess is in a state where there is no pipe radial direction support member in the pipe radial direction. In other words, since the area occupied by the tube-diameter support member is not required in the receiving recess when the diameter of the lock ring is increased, the depth of the receiving recess in the tube diameter direction is the same as that of the lock ring. Only the necessary distance is obtained, and as a result, the receiving port can have a shape with a small outer diameter.

Further, in the pull-out prevention pipe joint according to the present invention, the tube-diameter support member is made of an elastic member that is displaced into a locking position and a retracted position by elastic deformation.
Further, in the pull-out prevention pipe joint of the present invention, the tube axis direction support member and the tube diameter direction support member are formed of an integral elastic member, and the tube axis direction support member is the outer peripheral surface of the insertion port and the inner peripheral surface of the receiving port. It is characterized by forming a sealing material for sealing between the two.

  As described above, according to the present invention, the lock ring can be held at an appropriate position when connecting the receiving port and the insertion port, and the mounting can be ensured, and the outer diameter of the receiving port can be reduced. The filler such as gravel can be charged smoothly.

Sectional drawing which shows the pipe joint in embodiment of this invention The pipe joint in the embodiment is shown, (a) is a cross-sectional view showing the middle of the connection, (b) is a cross-sectional view before the connection The rubber ring and lock ring centering protrusion in the same embodiment are shown, (a) is a plan view, and (b) is a cross-sectional view taken along line AA in (a). Sectional drawing which shows the connection completion state of the pipe joint in the embodiment Sectional drawing which shows the piping state of the pipe joint in the embodiment

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In FIG. 1, a receiving port 2 is formed at the end of one tube 1, and an end of the other tube 3 forms an insertion port 4 to be inserted into the receiving port 2. The insertion slot 4 has a taper 5 whose diameter is reduced toward the distal end, and has an insertion recess 6 at a predetermined position on the outer peripheral surface of the insertion slot 4.

  A lock ring 7 is attached to the insertion recess 6, and the lock ring 7 has a structure that can be enlarged / reduced by one part, and the inner peripheral surface on the one end side facing the insertion opening 4 is closer to the opening end side. A taper 8 that expands the diameter is formed.

  The receiving port 2 has a receiving recess 9 on its inner peripheral surface, and the receiving recess 9 forms a space for accommodating the lock ring 7 so as to be expandable and contractible. A convex portion 10 bulging in the tube radial direction is formed on the bottom surface of the receiving recess 9 in an annular shape along the tube circumferential direction.

  A rubber ring 11 which is an elastic member serving as a tube axis direction supporting member for receiving the lock ring 7 in the tube axis direction is attached to the receiving recess 9, and the rubber ring 11 is connected to the outer peripheral surface of the insertion port 4 and the receiving port. It forms a sealing material that seals between the two inner peripheral surfaces and is locked in the tube axis direction by the convex portion 10 of the receiving recess 9.

  As shown in FIGS. 3 (a) and 3 (b), a plurality of lock ring centering protrusions 12 are provided on the rubber ring 11 as tube diameter supporting members for receiving the lock ring 7 in the pipe diameter direction and holding it in a predetermined position. Is formed as an elastic member integral with the rubber ring 11, and the lock ring centering protrusion 12 is formed at a predetermined width, for example, 10 mm width, at each of the eight equal points on the circumference of the rubber ring 11. In the present embodiment, the lock ring centering protrusion 12 is formed of an elastic member integrated with the rubber ring 11, but the lock ring centering protrusion 12 and the rubber ring 11 may be separate.

  The lock ring centering protrusion 12 is in a locking position that stands up in the tube axis direction in an unloaded free state, and locks the lock ring 7 in the tube radial direction at the locking position. Further, the lock ring centering protrusion 12 is in a retracted position where the lock ring centering protrusion 12 is laid down in the pressurized state in which pressure is applied by the expanding lock ring 7, and the outer periphery of the lock ring 7 in the tube radial direction in the retracted position. It is in a state of being retracted from the surface in the direction of the tube axis. That is, the lock ring centering protrusion 12 is displaced between the locking position and the retracted position due to its elastic deformation.

The operation of the above configuration will be described.
[Unconnected state]
As shown in FIG. 2B, the rubber ring 11 and the lock ring centering protrusion 12 are mounted in the receiving recess 9 of the receiving port 2 in the unconnected state where the insertion port 4 is not inserted into the receiving port 2. Then, the rubber ring 11 is locked by the projection 10 of the receiving recess 9.

  Next, the lock ring 7, which has been reduced in diameter by applying an external force, is inserted into the receiving port 2 and brought into contact with the rubber ring 11, and in a region surrounded by the lock ring centering projection 12. The lock ring 7 is installed inside the receiving recess 9 by releasing the external force.

The lock ring 7 accommodated in the receiving recess 9 is in a relaxed and free state with no load. The rubber ring 11 receives the lock ring 7 in the tube axis direction, and the lock ring centering projection 12 is the lock ring 7. Is locked in the tube diameter direction and held in place. In this state, the lock ring 7 is centered and positioned substantially concentrically with the tube axis.
[When connecting]
At the time of connection, as shown in FIG. 2 (a), the insertion port 4 is inserted into the receiving port 2, and the insertion port is inserted into the taper 8 of the lock ring 7, and the insertion port 4 is inserted into the taper 8 at the distal end of the receiving port. Push into. At this time, both the tapers 5 and 8 guide each other so that the insertion port 4 and the lock ring 7 can be easily combined, and the lock ring centering protrusion 12 causes the lock ring 7 to be in contact with the tube axis. Therefore, the lock ring 7 is securely concentrically opposed to the insertion opening 4, and the lock ring 7 fits normally into the insertion opening 4 without any problems such as twisting.

  With the rubber ring 11 supporting the lock ring 7 against the pressing of the insertion opening 4, the diameter of the lock ring 7 is expanded by the tip of the insertion opening 4 entering the lock ring 7, and the diameter of the lock ring 7 increases. Is inserted into the receiving recess 6. Therefore, the lock ring 7 can be held at an appropriate position when the receiving port 2 and the insertion port 4 are connected, and the mounting thereof can be ensured.

  When the diameter of the lock ring 7 is increased, the lock ring centering protrusion 12 is pressed by the lock ring 7 and elastically deformed to be displaced from the locking position to the retracted position, and the outer peripheral surface of the lock ring 7 in the tube radial direction. Retreat from the top in the direction of the tube axis.

Thus, when the diameter of the lock ring 7 is increased, the interior of the receiving recess 9 is in a state in which the lock ring centering protrusion 12 does not exist in the tube radial direction. In other words, since the area occupied by the lock ring centering protrusion 12 is not required in the receiving recess 9 when the diameter of the lock ring 7 is increased, the depth of the receiving recess 9 in the tube radial direction is locked. Only the distance necessary for expanding the diameter of the ring 7 is obtained, and as a result, the receiving port 2 can be formed into a shape having a small outer diameter.
[Consolidation completed]
As shown in FIG. 4, when the insertion recess 6 corresponds to the lock ring 7 by the advancement of the insertion slot 4, the lock ring 7 is reduced in diameter by an elastic restoring force and is fitted into the insertion recess 6. The lock ring centering protrusion 12 whose external force has been released stands up by the elastic restoring force and returns to the locking position.
[Laying]
As shown in FIG. 5, when pipes 1 and 3 are piped vertically in a well or the like, a vertical hole 13 for pipes pipes 1 and 3 is dug until a predetermined depth is reached. The inner diameter of the vertical hole 13 needs to be larger than the outer diameter of the receiving port. For example, when pipes 1 and 3 having a nominal diameter of 300 mm are piped, the vertical hole 13 having a diameter of 450 mm is excavated.

  After excavating the vertical hole 13, the pipes 1 and 3 are sequentially connected to each other, and the pipes 1 and 3 are suspended from the vertical hole 13 to be connected. After the piping is finished, gravel 14 is packed into the gap between the inner wall surface of the vertical hole 13 and the outer periphery of the pipes 1 and 3.

  At this time, the outer diameter of the pipe is increased at the receiving port 2, and the space between the inner wall surface of the vertical hole 13 and the outer peripheral surface of the receiving port is narrowed. However, as described above, in the present invention, the depth of the receiving recess 9 in the tube radial direction is only a distance necessary for the diameter expansion of the lock ring 7, and as a result, the receiving port 2 has a shape with a small outer diameter. Therefore, the space between the inner wall surface of the vertical hole 13 and the outer peripheral surface of the receiving port is wider than in the prior art, and gravel 14 filling the gap between the inner wall surface of the vertical hole 13 and the outer peripheral surface of the pipes 1 and 3 is received. Clogging around the mouth 2 can be suppressed, the gravel 14 can be filled smoothly without increasing the diameter of the vertical hole 13, and the excavation cost and gravel associated with increasing the diameter of the vertical hole 13 can be increased. The increase of consumption materials such as can be avoided.

  In addition, the lock ring 7 is held in an appropriate position when the receiving port 2 and the insertion port 4 are connected, and the mounting is ensured, so that the retaining function by the lock ring 7 can be fully exhibited and ensured. Can be secured.

DESCRIPTION OF SYMBOLS 1, 3 Tube 2 Receiving port 4 Inserting port 5 Taper 6 Inserting recessed part 7 Lock ring 8 Taper 9 Receiving recessed part 10 Convex part 11 Rubber ring 12 Lock ring centering protrusion 13 Vertical hole 14 Gravel

Claims (3)

  A receiving port that forms the end of one tube, an insertion port that forms the end of the other tube and is inserted into the receiving port, an insertion recess formed on the outer peripheral surface of the insertion port, and a diameter that is attached to the insertion recess A pipe ring center that receives the lock ring in the direction of the pipe axis in a pipe joint that includes a lock ring that can be expanded and contracted and a receiving recess that is a space formed in the inner peripheral surface of the receiving opening and accommodates the locking ring The tube support member and the lock ring are received in the tube diameter direction and held at a predetermined position, and the tube diameter direction support member is provided on the back side of the receiving port, and the tube direction support member locks the lock ring in the tube diameter direction. An escape prevention pipe joint characterized by being displaceable over a position and a retracted position retracted in the tube axial direction from the lock ring in the tube radial direction.   The escape prevention pipe joint according to claim 1, wherein the pipe radial support member is made of an elastic member that is displaced to a locking position and a retracted position by elastic deformation.   The tube axis direction support member and the tube diameter direction support member are made of an integral elastic member, and the tube axis direction support member forms a seal material that seals between the outer peripheral surface of the insertion port and the inner peripheral surface of the receiving port. The escape prevention pipe joint according to claim 1 or 2.

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