JP3210954B2 - Lifting device for weight leak holder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elevating device for safely and efficiently moving up and down and moving heavy objects. For example, the present invention is provided in a main steam pipe for a turbine installed in a power plant or the like. maintenance of a large main valve, for example, relates to a valve element handling heavier equipment for inspection, for example, the main steam stop valve; ground portion that is mounted in the lower portion of the (M ain S top V alve hereinafter referred MSV) Detachment (disassembly, disassembly,
The present invention relates to a lifting device for facilitating (assembly).

[0002]

2. Description of the Related Art High pressure steam pipes for steam turbines are used for various purposes such as inspection, repair, control, protection and the like.
(B) Main steam control valve (CV), (c)
Four types of valves, a compound intermediate valve and (d) a bypass valve, are arranged. As an example, a case where the present invention is applied to the MSV will be described below. As shown in FIG.
The MSVs are directly welded to the inlet of the control valve housing (42), and a plurality of MSVs are juxtaposed after the main steam piping header upstream of the main steam control valve (CV).

Further, the MSVs are integrally welded through lower sheet equalizers (31) so that the lower seat chambers (2) of the valve box (1) are connected to each other. The purpose of this is
However, even when the turbine is closed by a test or the like, the steam flowing into the turbine is not spilled. The bottom casing (4) of the lower seat chamber (2) has a through hole for a stem (valve rod) (6) hanging from the large valve body (5), and is mounted horizontally to mount the valve box (1). Thick plate-shaped heavy-weight leak holder to prevent leakage of high-pressure fluid from inside (8)
Are mounted with a plurality of bolts (10) from below.

[0004] The MSV has a function of closing quickly in an emergency at a closing speed of 0.1 seconds or less, and blocking the flow of steam into the turbine. By rapidly releasing the stem fixing means (35) in the coupling spacer (33) at the lower end of the stem (6), the stem (6) is rapidly lowered by the pulling force of the spring in the spring housing (37). ,
The large valve element (5) is seated (valve seat) (1) in the valve box (1).
By sitting in 1) and closing the steam supply. To open the closed valve, the valve is suspended from a large valve body (5) seated on a seat (11) in a valve box (1) having a steam inlet (13) and a steam outlet (15). The lower end of the stem (6) is pushed up by the hydraulic pressure of the control pack (39) against the pulling force of the spring. In the drawing, reference numeral (12) denotes a pressure seal head, (14) denotes a stem bush (fitting hole) of the pressure seal head, (16) denotes a ground,
(21) is an MSV stand, (41) is a valve box lid, (4)
3) a stud bolt for the lid (41), (45) a nut, (47) a strainer, (49) a drain in front of the seat, (51) a first stage stem leak from the stem bush (14), (53) represents a second stage stem leak.
Detailed descriptions of these components will be omitted except for those directly related to the description of the weight leak holder elevating device of the present invention.

[0005] As described above, since the MSV has a function to quickly shut off steam flow to the turbine in an emergency, periodic inspection and maintenance are the most important and frequent operations. In addition, since the MSV has one unit, for example, four units, the inspection and maintenance of the four units, including the time for disassembly and assembly, are performed with the power generation stopped. Therefore, it is essential to perform necessary and sufficient inspection and maintenance in a short time, safely and without damage such as mutual contact of parts. In the series of disassembly, inspection, maintenance, and assembling steps, the steps that require the most man-hours, are dangerous, and may cause damage due to mutual contact of parts are disassembly and assembling. The process of disassembling and assembling the leak holder (8), which has its own weight, is a major bottleneck in all the processes. In particular, the number of man-hours currently accounts for about 15% of the total man-hours.

[0006] Conventionally, in the inspection work of the main valve of the steam turbine, the disassembly of the leak holder (8), which is the first step, is as follows.
In a narrow MSV stand (21) surrounded by a plurality of MSV stand yokes (20) supporting the MSV,
First, in order to separate the valve stem (6) and the leak holder (8), a narrow MSV stand (21) using a hanging device such as a nylon sling or a chain block (not shown) is used.
It hanging descending inside, while provisionally received in square timber, remove the ground retainer (16a), sampling the ground (16), lower the leakage holder (8), a method of extracting from the valve stem (6) has been adopted However, since the gap between the leak holder (8) and the valve stem (6) is about 0.3 to 0.5 mm, when the leak holder (8) is lowered, it may come into contact with the valve stem (6) and be damaged. there were. Next, the extracted heavy leak holder (8) is manually moved out of the narrow MSV stand inside (21) for inspection and repair. These operations are temporary scaffolding operations, the space is very small, and the leak holder (8) has a weight of about 60 kg as described above. The disassembly and assembly work, including the installation and disassembly of the scaffold, took a lot of time. In addition, due to the strain contact between the inner wall of the valve stem hole of the leak holder (8) and the stem (6), the steam leakage, etc. There is a fear that the surface of the valve stem (6) may be damaged, which may cause an increase in the size of the stem. For example, disassembly and assembly of four MSVs required a total of 10.5 days. Then, the assembling operation is the reverse procedure of the disassembly.

[0007] That is, the conventional (a) multiple MSVs
It takes time to disassemble and assemble the table in order,
(B) Alignment and level adjustment during disassembly / assembly take time. During alignment, damage to the valve stem (6) due to unexpected contact between the leak holder (8) and the stem (6). Care must be taken to prevent this from happening, and care must be taken to adjust the level in situations where it is difficult to see, so as not to damage the seal on the mounting part of the leak holder (8). ) May cause damage to other parts when it is put in and out of the MSV stand (21). Also, since the weight is about 60kg, there is a danger from the safety aspect such as pinching or falling of hands. (D) Since the leak holders (8) are temporarily received in a state in which the timbers are simply stacked, there has been a problem that the work has to be performed in a state where the mounting is unstable.

In addition, as described above, with respect to the inspection work of the main valves of the steam turbine, it is required that the shutdown period for the inspection and maintenance of the steam turbine be short in order to minimize a decrease in the power generation operation efficiency. At present, inspection and maintenance are handled by human naval tactics during that period, so the cost of inspection and maintenance has risen significantly. Others have predicted that they may not be able to meet customer needs in the future.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems in the prior art, and to easily attach and detach a leak holder attached to a lower portion of an MSV for an operation of inspecting a main valve of a steam turbine. It is another object of the present invention to provide a leak holder elevating device that is safe and does not damage related components. More specifically,
(I) It is an object of the present invention to provide a leak holder elevating device that can be easily attached and detached, fits in a small space, and does not hinder the work. (Ii) The centering and level adjustment are easy, To provide a leak holder elevating device having a structure in which the core does not shift or tilt or can be adjusted. (Iii) The leak holder can be securely held in a stable state from disassembly to assembly, and care of the leak holder and its lower part. Therefore, an object of the present invention is to provide a leak holder elevating device which does not require the leak holder to be taken out of the stand.

[0010]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have made intensive studies and, as a result, invented a leak holder elevating device of the present invention. Therefore, the object of the present invention is to solve the problem (1) of the present invention by horizontally mounting the lower part of the casing at the bottom of the valve box having the fitting hole of the valve rod hanging down from the valve body, between the fitting hole and the valve rod. A lifting and lowering device for attaching and detaching a thick plate-shaped heavy leak holder for preventing leakage of high pressure fluid from a gap from a lower portion of the bottom casing. A pair of pedestals (a); and a pedestal vertical moving means (b) capable of vertically moving the at least one pair of pedestals while maintaining the same level in the vertical direction without tilting the leak holder. Means (c), and the cradle (a)
Where at least two of the plate-like member which hole is grave, traveling nut having a female thread groove in the inner periphery is fixed to the plate-like member of the screw shaft hole and the linear shaft hole having a penetrating vertically inside wall , The screw shuff
And the receiving table vertical moving means (b)
A screw shaft having a male screw that is vertically erected, is screwed into a female screw groove of the traveling nut, and has a male screw passing through a screw shaft hole drilled in the plate-like member; A linear shaft having a surface that is erected and penetrates the linear shaft hole and slides the inner wall thereof, and a female screw groove of the traveling nut is formed by meshing with a male screw of the screw shaft and rotating the screw shaft. through it consists jack having a liftable rotary handle the bearers: (a) in the vertical direction, before Symbol fixed means (c) are vertical 1
Having a pair of generators, between which the screw shaft and
Hold the upper and lower ends of the linear shaft, and attach
Wherein the jack is fixed and the pair of upper and lower generators is vertically detachably attached to the yoke at the bottom of the valve box. (2) "The cradle (a) comprises: (3) The device for raising and lowering the leak holder according to the above (1), further comprising a level adjuster for finely adjusting the vertical level of the plate member when the plate member is stopped. The linear shaft has an upper part supported by a bearing member and is stably erected, the leak holder elevating device according to the above (1), (4) “the screw shaft and the linear shaft”. And a driving body (d) for fixing the cradle vertical moving means (b) composed of a jack, the driving body (d) being vertically attached to the yoke at the bottom of the valve box by the two upper and lower fixing bolts. It is achieved by leakage holder lifting device "described in the paragraph (1), characterized in that it is fixed.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings, but the present invention is not limited to these embodiments. Here, FIG. 2 shows an outline of an arrangement relationship between the leak holder elevating device of the present invention and the leak holder, and FIG. 3 shows one example of the leak holder elevating device of the present invention.
It shows the outline of the example, where (A) shows the side and (B)
The figure shows a top view, and the figure (C) shows a top view of another example . FIG. 4 shows a mounting state when the leak holder elevating device according to the present invention is used.

In FIG. 2, the upper part of the MSV is schematically shown with only the main elements to facilitate understanding of the present invention. In the example of the leak holder elevating device (69) shown in FIG. 3, the plate-like member (70) is used in a pair with another similar plate-like member, for example, and the plate-like member (7) is used.
The leak holder can be supported in a horizontal state from below on the upper surface of 0), and can be moved vertically in the vertical direction while maintaining the horizontal state without tilting.

The plate-like member (70) has two types of holes, a screw shaft hole (71) and a linear shaft hole (72), each having a smooth inner wall.
On the lower surface of (0), a traveling nut (74) having a female screw groove (73) on the inner periphery is provided by a bolt (75) in a positional relationship such that the female screw groove (73) communicates with the screw shaft hole (71). Fixed. A screw shaft (76) having a male screw is screwed into the female screw groove (73) of the traveling nut (74), passes through a hole (71) located thereon, and the other linear shaft hole (72).
(72) has a linear shaft (7) having a smooth surface.
7) (77) respectively penetrate the linear shaft hole (7
2) is slidable vertically on the surface of the linear shaft (77).

Although not indispensable in the present invention, the plate-like member (70) of the apparatus of this example is provided with a sleeve (78) around the rear surface for the purpose of weight reduction and durability as shown in FIG. The screw shaft (76) has a structure having a concave inner surface that hangs down, and the screw shaft (76) is stably erected and the plate member (70) is always kept horizontal. Block (79) having a through hole therethrough is fixed to the surface of the plate member (70). In the apparatus of this example, two linear shaft holes (72) and two linear shafts (77) are provided, but it goes without saying that any number of these may be provided as long as one or more are provided.

The plate member (70) is further provided with a hole (90) having a female screw groove as a level adjuster in the present invention, and a fine adjustment plate (91) is provided in the female screw groove of the hole (90). ) Is screwed into a male screw body (92) having a head that fits loosely with the hole provided in the plate member (70).
Male screw body (92)
By rotating, the level of the fine adjustment plate (91) can be slightly raised and lowered, and the support state and the separation state of the leak holder by the plate member (70) can be finely adjusted. Of course, in the leak holder elevating device of the present invention, the fine adjustment plate (9
1) is not essential and can be omitted,
The shape structure, installation number or the like is also not necessarily limited to those in this example, it may have a structure as shown, for example, in C Fig.

A bearing member (80) for stably erecting the rotating screw shaft (76) is disposed above the screw shaft (76). ) And has a bearing hole (82) and a through hole (83). Bearing hole (82)
The upper end of the screw shaft (76) is rotatably loosely fitted in the shaft, and the linear shaft (77) passes through the through hole (83).

However, in the present invention, the bearing member (80) may have a hole that penetrates the upper ends of the screw shaft (76) and the linear shaft (77). 80). Further, when the screw shaft (76) and the linear shaft (77) can be erected vertically, the bearing member (80) can be omitted.

The lower end of the screw shaft (76) passes through a loose fitting hole of a frame member (86) fixed to the driving body (85). A jack (88) is fixed to the frame member (86) by a bolt (87), and the jack (88) is a rotating body (89) around which teeth meshing with the external threads of the screw shaft (76) are provided. The plate-like member (70) can be freely raised and lowered in the vertical direction through the female screw groove (73) of the traveling nut (74) by being manually rotated by a handle (not shown). The precursor (85) may be integral with the frame member (86).

The generator (81) is attached to the yoke (20) by a fixture (95), for example, a wing nut-bolt, and the generator (85) is attached by a fixture (96). Thereby, the leak holder elevating device of the present invention is preferably fixed, for example, in the MSV state (21) in an opposed arrangement. In other words, the leak holder elevating and lowering device of the present invention has the receiving stand (a), the receiving stand vertical moving means (b), and the fixing means (c), and the receiving stand (a) is mainly a plate-like. It consists member (70) and traveling nut (74), fine as the if necessary
Adjusting plate (91) as a level adjuster reinforcing member may have provided <br/> of cradle vertically moving means (b) is the screw shaft (76), linear shaft (77),
It is composed of a jack (88) , and the fixing means (c) can be arranged to fix the cradle vertical moving means (b). It is preferable, but not essential, that the jack (88) has a self-locking function so that the plate-like member (70) does not descend or tilt due to the weight of the leak holder.

Next, a description will be given of a mode of lifting and lowering the jack (88). The jack (88) is operated (manually) by operating a handle (this operation can be performed by electric power).
9) rotates and the screw shaft (76) rotates,
The traveling nut (74) mounted below the plate-like member (70) of the cradle (a) is moved up and down to move the plate-like member (7).
0) is moved up and down while maintaining the horizontal state. When the plate-like member (70) approaches directly below the leak holder, the up-and-down movement is stopped and the male screw body (92) as an adjuster is rotated to adjust the fine adjustment plate (91). ) Is slightly moved up and down to position the leak holder, and then the leak holder is gently received from the bottom casing (4) or delivered to the bottom casing (4).

As shown in FIG. 3, the leak holder elevating device according to the present invention comprises two upper and lower fixtures (81) and (85).
Before the inspection starts, it is attached to the yoke part (20) inside the MSV stand (21) and removed after the end.
The attachment and detachment are screwed and fastened with a wing nut which can be quickly and easily made. Then, during inspection, ascend and descend as necessary and stop at that position,
Work can be performed inside the V-stand (21).

That is, FIG. 3 shows that the leak holder lifting / lowering device of the present invention is installed in a pair inside the MSV stand (21), and is detachably attached to the MSV stand yoke (20), and the leak holder (8) is attached. The plate-like member (70) which is moved up and down by a jack (88) supports a part of its periphery from below. The elevating and lowering device of the leak holder according to the present invention is installed as a pair inside the MSV stand (21). Since the MSV is normally supported by two to four MSV stand yoke portions (20), the present invention is applied. The mounting device (95) is attached to the two MSV stand yoke portions (20) opposite to each other so as to be positioned inside the MSV stand (21).
The leak holder (8) is supported on the plate-like member (70) which is fixed and lifted up and down by the jack (88) by supporting a part of the periphery from below, and the jack (88) and a level fine adjustment plate as an adjuster After positioning by (91) and finely adjusting the level, the leak holder (8)
A plurality of bolts (10) attached to the bottom surface of the SV casing (4) from below are removed, the leak holder (8) is placed on the plate member (70), and the jack (88) is operated. to start lowering the rotary body (89) by the handle, inspection, the most suitable position in the maintenance and incidental operations like
Is stopped (the position of the display in the broken line), withdrawn from the valve stem (6), inspection, will be carried out maintenance work.

As shown in FIG. 3C, a plate-like member (70 ') is used instead of the one shown in FIG.
A leak holder support plate (70a) is slidably provided on the top, and a pair of slide holes (90a) of the support plate (70a) are provided.
(90a), the leak holder support plate (70a) is slid in the stem direction by a slide bolt (90b) and then fixed, thereby clamping the leak holder (8) in the center direction and forming a pair of The structure may be such that the leak holder (8) is supported from below by the plate-like member (70 ').

FIG. 4 shows a mounting state when the leak holder elevating device according to the present invention is used. The configuration and operation method of FIG. 4 will be understood based on the detailed description of FIGS. 2 and 3 described above.

As described above, the use of the leak holder lifting device according to the present invention requires a lot of man-hours, such as hanging down using a conventional hanging device such as a nylon sling or a chain block, and temporarily receiving it with a square bar. Moreover, dangerous work can be completely eliminated, and the MSV stand (21)
Since the inspection, maintenance and incidental work of the leak holder (8) can be performed inside, it is not possible to carry the leak holder (8) out of the MSV stand (21) except in special cases. It has run out. In addition, according to the present invention, for example, conventionally, three persons need to disassemble and assemble.
5 days namely it took 10.5 man-days, decomposition, requires only 1.5 days immediately Chi three day two people to assemble, those further in the past, which accounted for 15% of the total number of steps, It was reduced to 4%, and the working process was shortened, and at the same time, the effect of improvement in safety and quality was highly evaluated as a result of trial use. In addition, the device of the present invention is an important device of power generation equipment, MSV.
It goes without saying that the device of the present invention can be used not only in the use of the equipment in lifting and lowering and moving heavy objects in other facilities, but also in the lifting and moving and moving of heavy objects in other facilities. Can be. That is, the advantages of the device of the present invention are as follows: (1) The device can be easily attached and detached,
The size is small enough to fit in a small space and does not disturb the work.The centering and level adjustment can be easily performed.The center does not shift or tilt when ascending and descending. Can be done to
There is no need to take out the leak holder from inside the stand to clean the leak holder and its lower part; (2) No need to handle the leak holder (about 60 kg) directly by hand, It is possible to avoid the danger of falling, and to prepare hanging equipment such as a chain block, so that dangerous work such as sling work becomes unnecessary; (3) It is possible to completely prevent the occurrence of damage to leak holders, valve stems, etc. Since there is nothing to obstruct the view of the building, sufficient confirmation can be made especially at the time of assembly , shortening the construction period and reducing personnel.
It allows; (4) for lifting operation can handle, can contribute to labor reduced, since the portable possible is one that exhibits a very excellent effect that held horizontally transported is facilitated.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an MSV as an example to which the present invention is applied.

FIG. 2 is a diagram showing an outline of an arrangement relationship between a leak holder elevating device and a leak holder according to the present invention.

FIG. 3 is a diagram showing an outline of an example of a leak holder elevating device of the present invention.

FIG. 4 is a diagram showing a mounted state when the leak holder elevating device according to the present invention is used.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Valve box 2 Lower seat chamber 4 Bottom casing 5 Large valve body 6 Stem (valve rod) 8 Leak holder 10 Bolt 11 Seat (valve seat) 12 Pressure seal head 13 Steam inlet 14 Stem bush (fitting hole) 15 Steam outlet 16 Ground 16a Ground presser 20 Yoke 21 MSV stand 31 Lower seat equalizer 33 Coupling specer 35 Stem fixing means 37 Spring housing 39 Control pack 41 Lid 42 Control valve housing 43 Stat bolt 45 Nut 47 Strainer 49 Drain in front of seat 51 First stage stem leak 53 Second stage stem leak 69 Leak holder elevating device 70 Plate member 70 'Plate member 70a Leak holder support plate 71 Screw shaft hole 72 Linear shaft hole 73 Female screw groove 7 Traveling nut 75 bolt 76 screw shaft 77 linear shaft 78 sleeve 79 reinforcing block 80 bearing member 81 on precursor 82 bearing hole 83 through hole 85 under precursor 86 frame member 87 bolt 88 jack 89 rotating body 90 hole 90a slide hole 90b slides Bolts 91 Fine adjustment plate 92 Male screw body 95 Wing nut attachment 96 Wing nut attachment

Claims (1)

(57) [Claims] 1. A high pressure fluid is prevented from leaking from a gap between the fitting hole and the valve stem by being horizontally mounted on a lower portion of a casing at the bottom of a valve box having a fitting hole for a valve stem hanging from a valve body. A lifting and lowering device for attaching and detaching a heavy-plate heavy-weight leak holder from the lower portion of the bottom casing for at least one pair of pedestals (a) for supporting the leak holder horizontally from below. A means for vertically moving the at least one pair of pedestals while maintaining the same level in the vertical direction and vertically moving without tilting the leak holder; and a fixing means (c). The cradle (a) has at least two of a screw shaft hole and a linear shaft hole which penetrate vertically and have an inner wall.
A plate-like member having various kinds of holes, and a traveling nut fixed to the plate-like member and having an internal thread groove on an inner periphery thereof, are formed by the above-mentioned sliding member .
The cradle vertical moving means (b) is vertically erected, is screwed into a female screw groove of the traveling nut, and penetrates a screw shaft hole formed in the plate member. A screw shaft having a male screw to be screwed, a linear shaft having a surface erected in parallel with the screw shaft while maintaining an interval and penetrating the linear shaft hole and sliding on an inner wall thereof, and a male screw of the screw shaft mesh and consists jack having a rotating handle that can lift the cradle to (a) in the vertical direction via the female screw groove of the traveling nut by rotating the screw shaft and, before Symbol fixed means (c ) Has a pair of upper and lower generators,
Between the screw shaft and the linear shaft
Holding the lower end, the jack is fixed to the lower vehicle, and
The pair of upper and lower generators are vertically detachable from the yoke at the bottom of the valve box
An elevating device for a leak holder, which is attached to a device.