JP3124098B2 - Stretch tube handling tool for internal pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to handling of a stretch tube for an internal pump for mounting and removing a diffuser and a stretch tube incorporated in an internal pump for recirculating reactor water of an improved boiling water reactor. About the tool.

[0002]

2. Description of the Related Art An improved boiling water reactor (hereinafter referred to as ABWR)
Employs an internal pump for the recirculation pump and high-speed electric control for the control rod drive mechanism. The former does not require a recirculation piping connected to the inside of the furnace outside the furnace, so that the risk of reactor water leakage is greatly reduced. The latter has the advantage that the response of the control rod is excellent.

FIG. 6 schematically shows an ABWR.
Reference numeral 1 in the drawing indicates a reactor pressure vessel. A reactor core 2 composed of a plurality of fuel assemblies standing in the reactor pressure vessel 1 is arranged, and surrounds the reactor core 2 and has a support 8 from the bottom.
The shroud 3 is provided through the intermediary of the shroud 3, and the separator 6 and the dryer 7 are arranged above the shroud 3.

A water supply pipe 4 and a high-pressure steam nozzle 11 are connected to a side surface of the reactor pressure vessel 1, and the water supply pipe 4 is connected to a sparger 5 in the reactor pressure vessel 1. An internal pump 13 is mounted on the bottom between the inner wall of the reactor pressure vessel 1 and the shroud 3.

A control rod housing 12 of a control rod drive mechanism for inserting a control rod into the reactor core 2 is attached to the bottom of the reactor pressure vessel 1. The internal pump 13 is provided on the pump seat extending to the bottom of the reactor pressure vessel at equal intervals around the circumference, and the support 8 supports the shroud 3, and a water hole is formed in the support 8 in accordance with the arrangement of the internal pump 13. Is provided.

[0006] The cooling water flows between the fuel assemblies of the reactor core 2 through the water holes by the driving of the internal pump 13, boils and becomes a gas-liquid two-phase flow, and the steam and water are separated by the separator 6. The steam is dried by the dryer 7 and the high pressure steam nozzle 11
Sent to the turbine.

[0007] Condensate is sent to the water supply pipe 4,
Water is supplied from the outer periphery of the shroud 3 to the inner periphery of the reactor pressure vessel 1 by the internal pump 13 via the sparger 5, and recirculation in the reactor is performed by the internal pump 13.

FIG. 7 shows the internal pump 13 in an enlarged manner. That is, the stub tube 1a is erected at the bottom of the reactor pressure vessel 1, the reduced diameter portion 22a of the pump casing 22 is inserted into the stub tube 1a, and the tip is welded. By welding, the enlarged diameter portion 22b is opened downward from the bottom, and the lower end opening of the pump casing 22 is closed by the motor cover 33.

[0009] A diffuser 24 is provided between the shroud 3 and the inner wall of the reactor pressure vessel 1.
The lower portion of the stretch tube 27 that engages with the boss portion 24a is tightened with a tightening nut. The stub tube 1a is formed on the bottom surface of the boss 24a by a stretch tube 27.
The upper part is pressed and tightened. The propeller 23 is integrated with the shaft 26, and a motor in which the rotor 30 and the stator 31 are combined is disposed on an extension of the shaft 26.

The can 32 in the pump casing 22 covers the motor, but the motor is cooled by fresh water from the cold water pipe 10. The hydraulic pipe 9 pressurizes the secondary seal 29 and performs an axial seal with the shaft 26. Wear ring 25 is propeller 23
A small gap is uniformly provided on the outer periphery of the propeller 23 to allow the propeller 23 to rotate.

As described above, the internal pump 13 erects a plurality of stub tubes 1a on the bottom of the reactor pressure vessel 1, has a reduced diameter portion in the stub tube 1a, and has an increased diameter portion 22b protruding from the bottom. The pump casing 22 is integrated with the stub tube 1a by welding, and the bottom is also integrated by welding.

A diffuser 24 is provided on the stub tube 1a.
The stretch tube 27 that engages with the diffuser 24 is housed in the reduced-diameter portion 22a of the pump casing 22, and the stretch tube 27 is tightened with the tightening nut 28 to increase the surface pressure of the diffuser 24 and intervene. The packing is pressed so that the infiltration of the reactor water does not reach the pump casing 22.

A shaft 26 to which a propeller 23 is attached passes through a stretch tube 27 and hangs down to a diameter-increasing portion 22b of the pump casing 22. The outer circumference of the shaft 26 is sealed by the secondary seal 29, so that the reactor water does not enter the increased diameter portion 22b of the pump casing 22 at all. The motor composed of the rotor 30 and the stator 31 is housed in the increased diameter portion 22b,
Cooling with fresh water prevents damage to the coils of the rotor 30 and the stator 31.

FIG. 8 shows the internal pump 13 in FIG.
3 shows a pump casing 22 from which a motor and other functional parts have been removed. The pump casing 22 is integrally welded to the reactor pressure vessel 1 and the stub tube 1 a, and the increased diameter portion 22 extends from the bottom of the reactor pressure vessel 1, and its lower end is closed by a motor cover 33. The support 8 supporting the shroud 3 is provided with a water passage hole so that recirculated water flows into the core 2.

In the internal pump 13 having the above-described structure, for attaching and detaching the stretch tube 27, the tightening of the tightening nut 28 with the end of the stretch tube 27 and the unfastening of the tightening nut 28 are performed. Handling tools are used. On the other hand, in order to prevent the rotation of the tightening nut 28, a handling tool for pressing and releasing the lock sleeve which is fastened to and integrated with the pump casing 22 by the tightening nut 28 is used.

The former handling tool comprises a spanner, a rotating mechanism, a tensioner for a stretch tube, a hydraulic cylinder, a screw rod, and a drive mechanism for them. The latter handling tool is composed of a pressing die, a hydraulic cylinder, a hydraulic lifting mechanism, and the like.

[0017]

In the above-mentioned stretch tube handling tool, the wrench engaging portion of the tightening nut and the fitting portion of the lock sleeve of the tightening nut are recessed on the outer periphery of the tightening nut flange at the same place. The grooves formed and equally arranged are used as key points. Therefore, for example, in order to press the lock sleeve after tightening to interfere with the groove and prevent the lock sleeve from rotating, a pressing die to be fitted in the groove is required, and there is a problem that a lot of trouble is required for positioning.

By the way, a wrench work for mounting and removing the tightening nut, and a pressing and returning operation of the lock sleeve are provided on the wrench pedestal with a pressing die head for pressing and returning.
It is desirable to carry out each of the above operations only by exchanging these pressing heads.

That is, if the handling tool for screwing and releasing the tightening nut 28 with the tightening nut 28 of the stretch tube 27 and the handling tool for releasing the rotation stop of the lock sleeve 28 and the lock sleeve are integrated, respectively, the stretch tube It is not necessary to align the position of the press head on the spanner pedestal with the groove of the tightening nut at the time of mounting and removing the wrench.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems and to satisfy the above-mentioned demands. The present invention has been made to solve the above-mentioned problems, and to attach / detach a diffuser and a stretch tube of an internal pump, a propeller and a shaft, and a motor when attaching / detaching a motor. Another object of the present invention is to provide a handling device for a stretch tube for an internal pump, which is labor-saving and has good workability.

[0021]

SUMMARY OF THE INVENTION The present invention provides a tensioner,
A tensioner shaft for supporting the tensioner, a hollow piston provided on the outer periphery of the tensioner shaft, a cylinder for driving the hollow piston, a first piston guide provided to surround an upper portion of the hollow piston, First
A wrench pedestal integrated with the piston guide
A drive gear provided below the wrench pedestal, a drive pinion connected to the drive gear , and
A wrench or a press-type head that is detachably connected .

[0022]

[Effect] The fastening nut can be easily attached to and detached from the wrench, and can be replaced with the press-type portion of the lock sleeve at any time. In any operation, when the stretch tube is pulled by the tensioner, the tightening pressure on the stub tube can be kept constant.

In this state, the cylinder and the parts to be fixed thereto are raised and lowered by themselves. Although the stroke of the pressing die portion becomes larger than the stroke until the tightening nut is completely closed, the stroke limit is increased by removing the collar.

At the time of mounting the stretch tube, a wrench is first mounted on the wrench pedestal, but the tightening nut is engaged with the wrench, and the wrench is stopped by a matching groove or the like. The screw rod is rotated by the rotary drive device, the frame is raised, and stopped when the upper side of the frame comes into contact with the open end flange of the pump casing.

The functional parts of the frame are compactly arranged inside the cylindrical case, and a guide roller is provided outside the cylindrical case so as to follow the inner wall of the pump casing. A tensioner is provided at the head portion in the outer cylinder. When the tensioner shaft is rotated, the shaft moves up and down in relation to the fixed nut, and when the tensioner is lowered, the slide of the tensioner meshes with the groove inside the stretch tube.

Next, when hydraulic pressure is applied from the port of the cylinder, the tensioner shaft is stopped while pulling the stretch tube, but the cylinder side is raised, and the tightening nut thereabove is engaged with the spanner so that the end of the stretch tube is engaged. Contact with the screw end formed at Drive the torque motor,
Turn the wrench by rotating the drive pinion and drive gear, and screw the tightening nut into the stretch tube.

After the tightening is completed, the frame is lowered by the screw rod, the press head at the time of tightening is replaced with a spanner outside the pump casing, and the frame is raised again. In this case, the collar is removed and the stroke of the hydraulic cylinder is increased. The reason is that the stroke for further pressing the lock sleeve after the tightening of the tightening nut is slightly increased.

After positioning, the mating mold is inserted into the groove of the tightening nut except for the outside of the cylindrical portion of the lock sleeve by hooking the tensioner and pressed from the outside to form a projection in the groove mold.
The interference prevents the tightening nut from rotating.

After the pressing, the handling tool is lowered to complete the work of mounting the tightening nut. In the case of disassembly, the press die head is returned when disassembling by the reverse operation, and the protrusion of the lock sleeve is returned to its original position. Then, the spanner is bitten into the tightening nut and turned in reverse to reduce the oil pressure and remove the tightening nut.

By the above operation, the replacement position of the wrench with the wrench at the stage of ascending and descending by the screw rod can be made coincident with each other without having to measure each time only by replacing the pressing die head on the wrench base.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a tool for handling a stretch tube for an internal pump according to the present invention will be described with reference to FIGS. FIG. 1 shows that the handling tool according to the present embodiment is inserted into the pump casing 22 of the internal pump 13,
Further, a state where the rotary drive unit 46 is attached to the screw rod 45 is shown.

In FIG. 1, the rotation driving device 46 is connected to the hook 35.
And all except for the screw rod 45 are lifted. The tensioner 47 engages the slide 56 shown in FIG. 2 into the groove 27a of the stretch tube 27 and pulls it under the stretch tube 27 to increase the packing pressure between the diffuser 24 and the stub tube 1a shown in FIG. Things.

The tensioner 47 is attached to the tip of the tensioner shaft 17, and the outer periphery of the tensioner shaft 17 is surrounded by a cylinder 40. The cylinder 40 is provided with ports 41 and 42 for applying hydraulic pressure. ing. A drive gear 38 is provided outside the upper part of the tensioner shaft 17, and the drive gear 38 is meshed with a drive pinion 39. The drive pinion 39 is attached to the drive shaft 16, and the drive shaft 16 is rotated by the torque motor 43.

On the outer periphery of the tensioner shaft 17, a hollow piston 18 is provided.
And a cylinder 40 for hydraulically driving the hollow piston 18 is provided. A first piston guide 19 is provided so as to surround the upper part of the hollow piston 18, and a wrench pedestal 20 is provided integrally with the piston guide 19.

A drive shaft 21 is provided below the hollow piston 18.
The drive shaft 21 has a thrust shaft
A fixing nut 48 is provided via a support, and is provided below the fixing nut 48.
A spring is provided on the end face . In FIG. 1, the tightening nut 28 is shown in a state in which tightening has begun, and the wrench 36 is initially engaged with the tightening nut 28 as shown.

The tensioner 47 comprises an upper guide 55, a slide 56 and a lower guide 57 which surround a limiter (stopper) 54. The limiter 54 slides via a lever 58.
Is pivoted to. In the figure, reference numeral 59 denotes a spring,
Denotes a bearing, 61 denotes a coupling, 62 denotes a collar, 63 denotes a casing inner surface guide, 64 denotes a handle shaft, and 65 denotes a position indicating rod.

When the pressing tool is used, the collar 37 is removed to adjust the stroke. The drive gear 38 is a spanner 36
The function is performed to rotate the. Drive pinion
39 rotates the drive gear 38. Drive shaft 16 is drive pinion 39
Drive shaft. Since the tensioner shaft 17 is screwed with the fixing nut 48, the tensioner shaft 17 moves up and down when rotated.

The guide roller 15 slides on the inner wall of the pump casing 22, guides the compact handling tool, and moves at a specified position. Ports 41 and 42 are provided in the cylinder 40 on the ventral back of the piston portion of the tensioner shaft 17. The torque motor 43 has a torque that rotates the drive shaft 16 via a gear mechanism to rotate the spanner 36 so that the tightening nut 28 can be properly tightened.

The thrust collar 14 supports a screw rod 45. Casing flange 66 is a thrust collar
Supports 14 The frame 44 collectively supports the functional units. The exterior of the functional unit is covered with an outer cylinder 34, and a plurality of guide rollers 15 are provided on the outer periphery thereof.

The right and left screw rods 45 have a pair of left and right motion screws engraved on the entire length thereof, and are mounted on both sides of the frame 44 in a gate shape. When the screw rod 45 rotates by using the side of the frame 44 as a female screw, the frame 44 moves up or down.

A rotary driving device 46 for driving the screw rod 45 to rotate so as to synchronize the two driving devices with a chain or a gear. One of the rotation driving devices 46 rotates in a chain on a power supply side with a motor. A manual handle is also provided on the power supply side.

The upper part of FIGS. 2 and 3 shows the interrelationship between the slide 56 projecting by operating the lever 58 of the tensioner 47 and the groove 27a of the stretch tube 27. In the drawing, the initial movement position of the tightening nut 28 is shown. The lock sleeve 49 extends downwardly from the thin cylindrical portion 49a, and the boss portion is directly bolted to the pump casing 22.

The wrench 36 and the wrench base 20 are detachable, and when set, a claw 36a formed at the tip of the wrench 36 meshes with a plurality of concave grooves formed in the tightening nut 28. The collar 37 is a cylindrical collar that abuts inside the pump casing 22 as a stop position limiter at the tip of a component formed integrally with the small-diameter cylinder 53, and is removed when the rising stroke of the small-diameter cylinder 53 increases. . The stroke will be extended by the amount removed.

FIG. 3 is a view showing a state where the collar in FIG. 2 is removed when the pressing tool is attached. Tensioner 47
2 is the same as FIG. 2, but the tightening nut 28 is sufficiently tightened, and the thin cylindrical portion of the lock sleeve 49 is inserted into the groove of the tightening nut 28.
This shows a state in which 49a starts to be pressed by the pressing die head 50 at the time of tightening.

FIG. 3 shows a state in which the press die head 50 at the time of tightening is replaced by attaching and detaching a groove instead of the spanner 36 shown in FIG. FIG. 3 differs from FIG. 2 in that the tightening nut 28 is screwed, so that the stroke is further increased in order to further push the lock sleeve 49.
The collar 37 shown in the figure is the spanner pedestal 20 integrated with the small-diameter cylinder 53.
Has been removed from.

FIG. 4 is a schematic cross-sectional view for explaining when the rotation is stopped by the pressing die head 50 at the time of tightening. In FIG. 4, a projection is raised on the thin cylindrical portion 49a of the lock sleeve 49, which is bolted to the pump casing 22, for pressing. A thin cylindrical portion 49a enters the groove 51 along the outer periphery of the flange portion 27b of the stretch tube 27. As shown in FIG. 5, when the press die head 50 further advances from the state shown in the figure, the thin cylindrical portion 49a is caught in the bent groove 51 to prevent rotation.

In FIG. 5, a pressing projection is formed using the pressing head 50a at the time of disassembly so as to fit into the center of the groove 51 contrary to the state of FIG. The projection supports the thin cylindrical portion 49a. In FIG. 5, when the pressing die head 50a at the time of disassembly further advances, the bent thin cylindrical portion 49a of the lock sleeve 49 of FIG. 4 is restored to a cylindrical shape, and the detent is released.

Next, a specific use example of the above-mentioned handling tool will be described. Replacement or removal of stretch tube 27, inspection,
At the time of periodic inspections such as reassembly, the internal pump stops and prepares for it. At the time of disassembly, fresh water in the pump casing 22 is drained, and the inside of the enlarged diameter portion of the casing 22 is used as an air chamber.

Next, the motor cover 33 is removed, the motor is detached from the shaft 26, the motor cover 33 is again closed, the pump casing 22 is filled with fresh water, and the propeller 23 and the shaft 26 are taken out from the furnace as a unit.

Thereafter, a blanking block is placed on the opening flange of the stretch tube 27 at the engaging portion between the diffuser 24 and the stretch tube 27, and the upper surfaces of the stretch tube 27 and the stub tube 1a are loaded and the stretch tube 27 is Close the opening with sticky packing under the blanking block.

Thereafter, the fresh water in the pump casing 22 is drained, and the motor cover 33 is removed. Thereafter, preparations are made for feeding the stretch tube handling tool into the pump casing 22. The tip of the screw rod 45 is fixed to the thrust collar 14 of the pump casing 22, and the frame 44 is screwed to the screw rod 45.

The stamping head on the spanner pedestal 20 is replaced and a new stamping head 50 for disassembly for releasing rotation of the tightening rod is released.
Install a. The collar 37 on the frame integrated with the small-diameter cylinder 53 is removed. Next, the rotation drive unit 46 is rotated, and the two screw rods 45 are rotated to raise the frame 44.
When the frame 44 comes into contact with the casing 22, it stops rising,
Positioning ends.

At this time, the pressing die head 50a is in the state of FIG.
Is in a fixed state. Subsequently, the tensioner shaft 17 is rotated, and the engaging piece of the tensioner 47 is pushed into the groove of the stretch tube 27 to press the cylinder 40 from the port 41. Stretch tube 27 will be in the state of being pulled in as much as possible,
When the oil pressure is further increased to the specified oil pressure, the cylinder side starts to float, and the lock sleeve 49 starts to be pressed and deformed in the state of FIG.

When the stroke is full, the lock sleeve 49
The thin-walled cylindrical portion 49a is restored to the old state, and the spanner pedestal 20 is ready to be mounted. Using the rotary drive again, lower the frame and replace the press-type head of the spanner pedestal 20 with the spanner 36.
And the collar 37 is attached, and the frame is raised again.

Since the engaging portion of the wrench 36 is engaged with the flange groove of the stretch tube at exactly the same position, after positioning, the tensioner is operated, the hydraulic pressure is applied, the drive shaft 16 is rotated using the torque motor 43, and the drive pinion 39 and Drive gear
Rotate 38 to rotate the spanner 36 in the direction opposite to the direction when assembling.

When the tightening nut 28 starts to loosen, the spanner 36 is originally supported by the support 52 with a spring, so that the tightening nut 28 starts to come off. When it comes out, the end of the support 52 projects from the spanner pedestal 20 so that it can be seen. After that,
The handling tool is again moved to the pump casing 22 by the rotary drive 46.
After that, the screw rod 45 is detached from the casing flange 66, and the handling tool is suspended by the hook 35 to disengage the screw rod 45 and move.

Here, the pump casing is covered with a motor cover and filled with fresh water, the upper blanking block is removed, and the diffuser 24 and the stretch tube 27 are removed. This completes the disassembly.

At the time of reassembly, the diffuser 24 and the stretch tube 27 are inserted, the blanking block is mounted thereon, the fresh water in the pump casing 22 is removed, and the tightening nut 28 and the spanner pedestal 20 are removed. The handling tool is inserted into the pump casing with the engaged head, and the tension nut 28 is combined with the stretch tube 27.

Next, the head of the handling tool is replaced, and the color is changed.
Remove the 37, attach the stamping heads 50 and 50a, insert the handling tool, press the lock sleeve 49 to prevent it from turning, lower the handling tool, move it, and then tighten the secondary seal 29 with the tightening nut. 28
It is attached to the pump casing 22 below.

After closing the motor cover 33 and injecting fresh water, removing the upper blanking block, inserting the propeller 23 and the shaft 26 to remove the fresh water, removing the motor cover 33, attaching the water immersion motor, and attaching the motor cover 33 To finish reassembly. The operation is performed by cooling the motor with fresh water, and high water pressure is applied to the secondary seal 29 to enhance the sealing effect.

[0061]

According to the present invention, it is possible to perform four operations of stopping the rotation of the tightening nut of the stretch tube from the tightening of the tightening nut, and removing the tightening nut from the removal of the detent, by changing the head of a set of handling tools. it can. In addition, the engaging portion of the tightening nut engages with a plurality of concave grooves of the flange of the stretch tube, but since the head is converted by the screw rod method, it is not necessary to confirm the nut position each time it is aligned. It is extremely efficient, labor-saving, and has good workability.

[Brief description of the drawings]

FIG. 1 is an elevational view, partially in section, of an embodiment of a tool for handling a stretch tube for an internal pump according to the present invention.

FIG. 2 is an enlarged longitudinal sectional view showing a main part in FIG. 1;

FIG. 3 is a longitudinal sectional view showing a state where a collar in FIG. 2 is removed.

FIG. 4 is a longitudinal sectional view showing the pressing die head at the time of tightening in FIG.

FIG. 5 is a longitudinal sectional view showing the pressing head at the time of disassembly in FIG. 1;

FIG. 6 is a longitudinal sectional view schematically showing an improved boiling water reactor.

FIG. 7 is a longitudinal sectional view showing the internal pump of the nuclear reactor in FIG.

8 is a longitudinal sectional view showing a pump casing in a state where the internal pump in FIG. 7 is disassembled.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Reactor pressure vessel, 1a ... Stub tube, 2 ... Core, 3 ... Shroud, 4 ... Water supply pipe, 5 ... Sparger, 6
... Separator, 7 ... Dryer, 8 ... Support, 9 ... Hydraulic tube, 10 ... Cold water tube, 11 ... High pressure steam nozzle, 12 ... Control rod housing, 13 ... Internal pump, 14 ... Thrust collar, 15 ... Guide roller, 16 ... drive shaft, 17 ... tensioner shaft, 18 ... hollow piston, 19 ... first piston guide, 20
... Spanner pedestal, 21 ... Drive shaft, 22 ... Pump casing, 22a ... Reduced diameter part, 22b ... Diameter increasing part, 23 ... Propeller, 24 ...
Diffuser, 25 ... Wear ring, 26 ... Shaft, 27 ...
Stretch tube, 27a ... groove, 27b ... flange, 28
... Tightening nut, 29 ... Secondary seal, 30 ... Rotor, 31 ... Stator, 32 ... Can, 33 ... Motor cover, 34 ... Outer cylinder, 35 ...
Hook, 36 ... Spanner, 36a ... Claw, 37 ... Collar, 38 ... Drive gear, 39 ... Drive pinion, 40 ... Cylinder, 41,42 ... Port, 43 ... Torque motor, 44 ... Frame, 45 ... Screw rod, 46 ... Rotational drive, 47… Tensioner, 48… Fixed nut, 49… Lock sleeve, 49a… Thin cylindrical part, 50,
50a: stamping head, 51: groove, 52: support, 53: small diameter cylinder, 54: limiter, 55: upper guide, 56: slide,
57 ... Lower guide, 58 ... Lever, 59 ... Spring, 60 ... Bearing, 61 ... Coupling, 62 ... Collar, 63 ... Casing inner surface guide, 64 ... Handle shaft, 65 ... Position indicator rod, 66 ...
Casing flange.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Kazuo Sakamaki, 2-4-4, Suehirocho, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture Inside Keihin Works, Toshiba Corporation (72) Kazuo Yagi, Kazuo Yagi Tennoharaku, Matsukawa-cho, Fukushima, Fukushima Prefecture No. Kitashiba Electric Co., Ltd. (72) Inventor Shigeru Watanabe 4-7-7 Shiba, Minato-ku, Tokyo Inside Itel Technical Service Co., Ltd. (56) References JP-A-58-42997 (JP, A) JP-A-58 JP-A-42998 (JP, A) JP-A-62-96796 (JP, A) JP-A-62-228978 (JP, A) JP-A-63-57904 (JP, A) JP-A-4-315994 (JP, A) (58) Fields surveyed (Int. Cl. ⁷ , DB name) G21C 15/243 G21C 19/02

Claims (1)

(57) [Claims] 1. A tensioner, a tensioner shaft for supporting the tensioner, a hollow piston provided on an outer periphery of the tensioner shaft, a cylinder for driving the hollow piston, and an upper portion of the hollow piston are provided. First
, A wrench pedestal provided integrally with the first piston guide, a driving gear provided below the wrench pedestal, and a driving gear connected to the driving gear.
A pinion and a switch removably connected to the spanner base.
A handling device for a stretch tube for an internal pump, comprising: a panner or a pressing head .