JPH0656234B2 - Bellows fittings for piping - Google Patents

Description

TECHNICAL FIELD The present invention relates to a bellows joint used for piping of a nuclear power plant, an energy plant and the like.

(Prior Art) Conventionally, the universal expansion joint 1 shown in FIGS. 4A and 4B has been used for the thermal expansion absorption of piping in nuclear power plants, energy plants and the like. This universal expansion joint 1 connects short pipes 4 and 4'to both ends of the joint pipe 2 through bellows 3 and 3 ', and connects a flange 5 of the short pipe 4 and a bracket 6 on an upper middle side of the joint pipe 2. Tie rod 7 between
The tie rod 7'on the flange 5'of the short pipe 4'and the bracket 6'on the lower middle side of the joint pipe 2, and the flanges 8 and 8'at both ends of the joint pipe 2 and the short pipe. Metal fittings 9, 9 ', 10, 10' are fixed to the flanges 5, 5'of 4, 4 ', respectively, and tie bolts 11, 11' are fixed by tension between the metal fittings 9, 10 and between 9 ', 10'. It consists of Incidentally, 12
Is a slot ring fitted in the valleys of bellows 3, 3 ',
It is fastened and fixed with bolts and nuts.

The universal expansion joint 1 having such a structure absorbs the axial displacement by the axial deformation of the two bellows 3, 3 '.
Displacement in the direction perpendicular to the axis of 60 ° is two bellows 3, 3 '
Can be absorbed by angular deformation. That is, the displacements in the X, Y, and Z axis directions can be absorbed by the bellows 3, 3 '.

(Problems to be Solved by the Invention) By the way, the universal expansion joint 1 described above has bellows 3, 3'connected to short pipes 4, 4'at two fixed ends.
Therefore, it is difficult to mechanically suppress the displacement of the pipes in the X, Y, and Z directions as an assumed designed deformation amount while maintaining the parallel surfaces of the short pipes 4 and 4 '. In other words, since the clearance between the tie rod 7 and the rod insertion holes (not shown) of the flanges 5, 5'is large, the flanges 5, 5 '
The degree of freedom in the Y and Z axis directions of the bellows 3, 3'between the surfaces is large. Therefore, the bellows 3, 3'cannot be restrained within the range of the designed deformation amount assuming the short pipes 4, 4 ', an excessive load is applied, and it is damaged when used for many years. Is lacking in safety and reliability.

Therefore, the present invention is intended to provide a bellows joint for piping which can solve the above problems.

(Means for Solving Problems) A bellows joint for piping of the present invention for solving the above problems connects three short pipes by bellows, and positions the outer circumferences of both outer short pipes at the same facing position. Each of the studs has a fixed stud, and each stud has an arm slightly slidably projecting in parallel with the axis toward the short tube in the middle, and a gimbal arranged on the outer peripheral side of the bellows at the tip of each arm. The ring is supported so as to be slightly rotatable in the direction perpendicular to the axis, and an intermediate stud is fixed at a position offset by 90 degrees from the arm on the outer periphery of the intermediate short tube, and both outer short tubes are provided on both sides of the intermediate stud. The arms are provided so as to be slightly slidable in parallel with the axis, and the gimbal rings are coupled to the tips of the arms so as to be slightly rotatable in the direction perpendicular to the axis.

(Operation) The bellows joint for piping of the present invention configured as described above is used by connecting and fixing both outer short pipes to the pipe,
The axial displacement of thermal expansion due to the high temperature fluid flowing in the pipe is
The axial deformation of the two bellows is absorbed, and the axial displacement in the 360 ° direction is absorbed by the angular deformation of the two bellows. That is, the displacements in the X, Y, and Z axis directions are absorbed by the bellows. When the two bellows become excessively deformed in the X-axis direction, the arms protruding from the outer short tube sides toward the intermediate short tube and the outer short tube sides from the intermediate short tube side. The sliding of the arm projecting toward the axis stops in the axial direction, and the deformation of the two bellows in the X-axis direction is restricted. When the two bellows become excessively deformed in the Y-axis direction, the two gimbal rings rotate about the tips of arms protruding from the outer short tube side to the intermediate short tube side. Stops and the deformation of the two bellows in the Y-axis direction is restricted. Further, when the two bellows are excessively deformed in the Z-axis direction, the two gimbal rings stop rotating about the tips of the arms protruding from the intermediate short tube side to the outer short tube sides. The deformation of the two bellows in the Z-axis direction is restricted. Thus, the two bellows can suppress the displacement of the pipe in the X, Y, and Z directions within the range of the designed deformation amount while maintaining the parallel surfaces at both ends of the pipe.

(Embodiment) An embodiment of the pipe bellows according to the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal front view of an upper half portion, FIG. 2 is a plan view of a rear half portion in a cross section, and FIG. 3 is a side view taken along the arrow A in FIG. 1, in which 20 is a left short pipe, 21 is an intermediate short pipe, 22 is a right short pipe, and these three short pipes 20, 21, 22 are bellows 2
It is connected at 3,24. Left and right outer short pipes 20, 2
The studs 25 and 2 are provided at front and rear facing positions on the outer circumference of the stud 2, respectively.
5 ', 26, 26' are fixed horizontally and each stud 25,
Arms 27, 27 ', 28, 28' are provided at the distal ends of 25 ', 26, 26' so as to be slightly slidable in parallel with the axis toward the intermediate short tube 21 side. That is, the studs 25 and 2
Two rectangular convex portions 29 and stoppers 30 parallel to the axis are provided on the tip surfaces of 5 ', 26, 26', and the rectangular convex portions 2
Two rectangular holes 31 which are slightly longer than the convex portion 29 formed in the base end side of the arms 27, 27 ', 28, 28' in parallel with the axis are fitted to the hole 9 to form the holes 31. An axial clearance C is formed between the studs 25, 2 and the protrusion 29.
A cover plate 32 is put on the tip surfaces of 5 ', 26, 26', and bolts 33 are screwed through the cover plate 32 to the convex portion 29 to attach arms 27, 27 ', 28, 28'. Therefore, these arms can slide in the axial direction within the clearance C. This arm 27,2
Gimbal ring 3 is attached to the tip of 7 ', 28, 28'.
4, 35 are supported so as to be slightly rotatable in the direction perpendicular to the axis. That is, the tip ends of the arms 27, 27 ', 28, 28' are fitted into the concave grooves 37 of the coupling fittings 36 provided at the front and rear facing positions of the gimbal rings 34, 35, and are pivotally supported by the pins 38. The cover 36 ′ is fitted and attached to the pin 38 on the outer surface of the coupling fitting 36, and the plate 39 is screwed into the pin 38 to fix the cover 39. The portion is expanded by being tapered on both left and right sides in the axial direction, and a clearance C'is formed between the tip portion of the arms 27, 27 ', 28, 28'. Therefore, the gimbal rings 34 and 35 can rotate within the clearance C ′ while being displaced in the Y-axis direction perpendicular to the axis. Studs 40, 40 'are vertically fixed at the upper and lower opposite positions of the outer circumference of the intermediate short pipe 21.
Arms 41, 41 ', 42, 42' are provided on both left and right ends of the tip 40 'so as to be slightly slidable toward the outer short tubes 20, 22 in parallel with the axis. That is, the stud 40,
Two rectangular protrusions 43 parallel to the axis are provided on the left and right sides of the tip surface of 40 ', and the arms 41, 4 are attached to the protrusions 43.
Two rectangular holes 44, which are slightly longer than the convex portion 43 formed in parallel with the axial center on the base end side of 1 ', 42, 42', are fitted to form the hole 44 and the convex portion 43. An axial clearance C is formed between them, a cover plate 45 is applied to the tip surfaces of the studs 40, 40 ', and a bolt 46 is screwed through the cover plate 45 to the convex portion 43 to arm 41, 41',
42 and 42 'are attached. Therefore, these arms can slide in the axial direction within the clearance C. The gimbal rings 34, 35 are supported at the tips of the arms 41, 41 ', 42, 42' so as to be slightly rotatable in the axis-perpendicular direction. That is, the arms 41, 41 ', 42, 4
Attach the gimbal ring 3 to the tip of 2'as shown in FIG.
4 and 35 are fitted in the concave grooves 48 of the fittings 47 provided at the upper and lower opposite positions and pivotally supported by the pins 49, and the cover 50 is fitted on the outer surface of the fittings 47 by fitting the pins 49, 49
A bolt 51 with a plate is screwed to the cover 50 and fixed to the cover 50. The recessed groove 48 is expanded by tapping both side surfaces of the recessed groove 48 to the left and right in the axial direction from the central portion. A clearance C'is formed between the tip ends of the marks 42 ', 42' and 42 '. Therefore, gimbal ring 3
4, 35 can rotate within the range of the clearance C ′ while being displaced in the Z-axis direction perpendicular to the axis.

In the figure, 52 is a short pipe 20, 21, 22 and a bellows 23,
The short tube 2 on the right side, which is a cylinder arranged so as to cover the outer circumference of 24.
2 is fixedly supported on each stud 25, 25 ', 26, 2
6 ', 40, 40' are penetrated so as not to hit the cylindrical body 52.

The pipe bellows joint of the present invention configured as described above,
For example, when it is used to connect the high temperature pipes of the multipurpose high temperature gas experimental reactor, the short pipes 20 and 22 on both the left and right sides are respectively connected to the high temperature pipes to form two fixed ends, and the axial displacement of the thermal expansion due to the high temperature fluid flowing in the pipes. Is absorbed by the axial deformation of the two bellows 23, 24, and the displacement in the direction perpendicular to the axis is absorbed by the angular deformation of the two bellows 23, 24 in the direction of 360 degrees. When the bellows 23, 24 are deformed in the axial direction, the arms 27, 27 ', 28, 28', 41, 4
1 ', 42, 42' slide axially along the convex portions 29, 43 through the rectangular holes 31, 44. When the bellows 23, 24 are angularly deformed in the direction of 360 degrees, the gimbal rings 34, 35 displace the pin 38 while being displaced in the Y-axis direction perpendicular to the axis at the tips of the arms 27, 27 ', 28, 28'. It rotates about the center and has arms 41, 41 ', 42, 4
The tip of 2'rotates while being displaced in the Z-axis direction perpendicular to the axis.

However, when the two bellows 23, 24 are excessively deformed in the X-axis direction, the arms 27, 27 ', 28,
Since the sliding of 28 ', 41, 41', 42, 42 'in the axial direction is within the range of the clearance C, the sliding of these arms is stopped and the deformation of the bellows 23, 24 in the X-axis direction is restricted. To be done. In addition, an excessive Y on the two bellows 23, 24
When the axial deformation occurs, the rotation of the arms 27, 27 ', 28, 28' of the two gimbal rings 34, 35 about the pins 38 at the tips thereof causes the clearance C '.
These gimbal rings 34, 35 are within the range of
Displacement of the bellows 23, 2 is restricted.
Deformation of No. 4 in the Y-axis direction is restricted. Further, when excessive deformation of the two bellows 23, 24 in the Z-axis direction occurs, the arms 41, 2 of the two gimbal rings 34, 35,
Since the rotation around the pin 49 at the tip of 41 ', 42, 42' is within the clearance C ', the displacement of these gimbal rings 34, 35 in the Z-axis direction is restricted,
Therefore, the deformation of the bellows 23, 24 in the Z-axis direction is restricted.

Thus, the bellows 23 and 24 can suppress the displacement of the pipe in the X, Y, and Z directions within the designed deformation range while maintaining the parallel surfaces at both ends of the pipe.

In the bellows joint for piping of the above-mentioned embodiment, the short pipe 2
0, 21, 22 and the bellows 23, 24 on the outer periphery of the cylindrical body 5
Although 2 is arranged, this may be omitted depending on the high temperature pipe to be connected.

(Effects of the Invention) As can be seen from the above description, the pipe bellows joint of the present invention absorbs the axial displacement of thermal expansion due to the high-temperature fluid flowing in the pipe by the deformation of the two bellows in the X-axis direction.
The displacement in the degree direction can be absorbed by the angular displacements in the Y-axis and Z-axis directions of the two bellows. When these bellows become excessively deformed in the X-axis direction, three short tubes and two
By stopping the sliding of the arm connecting the individual gimbal rings in the axial direction, deformation of the bellows in the X-axis direction is restricted,
When excessive deformation occurs in the Y-axis direction, the displacement of the two gimbal rings in the Y-axis direction is restrained, so that the deformation of the bellows in the Y-axis direction is restricted, and the Z
When excessive deformation occurs in the axial direction, the displacement of the two gimbal rings in the Z-axis direction is restricted,
The deformation of the bellows in the Z-axis direction is restricted. Therefore, the bellows keeps the parallel surfaces of both ends of the pipe,
Since the deformation in the Y and Z directions can be suppressed within the designed range of deformation, the bellows will not be overloaded and will not be damaged even after many years of use. ， It has an excellent effect of improving reliability.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of an upper half part showing an embodiment of a bellows joint for piping according to the present invention, FIG. 2 is a cross sectional plan view of the latter half part, and FIG. 3 is a side view taken along arrow A of FIG. The figure shows a conventional universal expansion joint, where a is a vertical front view of an upper half portion and b is a front view in a state of being angularly deformed. 20, 21, 22 ... Short pipe 23, 24 ... Bellows 25, 25 ', 26, 26', 40, 40 '... Stud 27, 27', 28, 28 ', 41, 41', 42, 4
2 '... Arm 34, 35 ... Gimbal ring 38, 49 ... Pin

Claims (1)

[Claims] 1. Three short pipes are connected by bellows, and studs are fixed at the same opposing positions on the outer peripheries of both outer short pipes, respectively.
An arm is provided on each stud so as to be slightly slidable in parallel with the axis toward the short tube in the middle, and a gimbal ring arranged on the outer peripheral side of the bellows is slightly attached to the tip of each arm in the direction perpendicular to the axis. An stud is supported rotatably, and an intermediate stud is fixed at a position deviated by 90 degrees from the arm on the outer circumference of the intermediate short pipe. Both sides of the intermediate stud are parallel to the axial center toward both outer short pipes. A bellows joint for piping, in which arms are provided so as to be slightly slidable, and the zirbal rings are coupled to the tip ends of the arms so as to be slightly rotatable in the direction perpendicular to the axis.