JP2002256815A - Steam turbine generator facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide steam turbine generator facilities simplifying a piping around a steam turbine, so as to create a sufficient space to enhance efficiency and safety of construction work and maintenance work. SOLUTION: In the steam turbine generator facilities equipped with a steam turbine, a steam generating device and a steam condenser, a main steam distributing tube that sends steam for driving turbine from the steam generating device to the steam turbine is connected to the steam condenser or a turbine nozzle out of a coupling shell, through a side board of the steam condenser or a side board of the coupling shell that couples the steam condenser and the steam turbine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a steam turbine power generation facility or a combined cycle power generation facility combining a steam turbine and a gas turbine (hereinafter referred to as a steam turbine power generation facility including the two facilities).
In particular, the present invention relates to a communication path of a main steam pipe to a steam turbine and a supporting structure thereof.

[0002]

2. Description of the Related Art Generally, a steam turbine for a power generation business is supported above a condenser by a gantry made of steel or reinforced concrete, communicates with an upper part of the condenser through an opening of the gantry, and exhausts the condenser. The steam supplied from the boiler flows into the steam turbine through a main steam pipe connected to a nozzle of the steam turbine. In general, steams having different temperatures and pressures are supplied from individual main steam pipes through individual turbine nozzles. In addition, the turbine nozzle is provided outside the connecting cylinder that connects the steam turbine and the condenser.

[0003] A steam turbine for a power generation business is generally installed in a building. The arrangement method of the steam turbine in the building can be classified into two methods, a method in which the axis of the turbine is arranged parallel to the boiler, and a method in which the turbine axis is arranged at a right angle. In particular, in a combined-cycle power plant called a single-shaft type in which a gas generator and a steam turbine are used together to drive one generator, the latter system is generally adopted because a plurality of shafts are arranged in parallel.

[0004] The prior art relating to the steam turbine power generation equipment is described in, for example, Japanese Patent Application Laid-Open No. 61-215406.

[0005]

In a steam turbine for a power generation business, generally, steam having different temperatures and pressures is supplied from separate main steam pipes through separate turbine nozzles. Is complicatedly routed. In addition, since a valve for controlling the amount of steam flowing into the turbine is installed in the main steam piping, it is necessary to secure space for its operation and inspection work. Is difficult to do. Furthermore, the complexity of the piping route and the narrow working space not only lead to a longer construction process and an increase in construction costs due to a decrease in work efficiency in the construction work of the power plant, but are also undesirable in terms of safety. .

By the way, as described above, in the method in which the axial direction of the turbine is arranged at right angles to the boiler, the depth of the building is large and the construction cost is high. Therefore, it is desirable to shorten the turbine shaft length. It is. The axial length of the steam turbine is
When compared with turbines of the same type and same output, it is largely determined by steam conditions and thermal efficiency, but even if the turbine shaft length is structurally shortened due to changes in turbine blade length or shape, etc. Due to the relationship between the amount of steam and the amount of steam, the required cross-sectional area of the connecting cylinder, which is the connecting portion between the steam turbine and the condenser, hardly changes. Therefore, when the turbine shaft length is shortened,
The connecting cylinder becomes relatively large with respect to the turbine shaft length, and it is difficult to install a turbine nozzle space outside the connecting cylinder for connecting the main steam pipe from below the turbine as in the related art.

As described above, when the turbine shaft length is short and it is difficult to connect the main steam pipe from below the turbine,
There is a means to connect a part of the main steam pipe from above the turbine so as not to interfere with the connecting cylinder.However, when connecting from below the turbine, the main steam pipe and main pipe are connected from the beam below the turbine installation floor. While it is possible to support the valve,
When connecting from above the turbine, it is necessary to support the main steam pipe and main valve from above the turbine installation floor, which makes the support structure complicated and turbine maintenance work complicated.
Furthermore, since the piping is routed on the turbine installation floor, the turbine maintenance space is reduced, and the appearance is also undesirable.

SUMMARY OF THE INVENTION An object of the present invention is to provide a steam turbine power generation system which simplifies piping around a steam turbine, creates a space margin, and improves the efficiency and safety of construction work and maintenance work. It is in.

[0009]

The object of the present invention is to provide a steam turbine power plant equipped with a steam turbine, a steam generator, and a condenser, wherein a main steam for supplying driving steam from the steam generator to the steam turbine is provided. This is achieved by connecting a pipe through the side plate of the condenser or the side plate of the connecting cylinder connecting the condenser and the steam turbine, and connecting the pipe to the turbine nozzle from inside the condenser or the connecting cylinder.

[0010]

FIG. 1 shows an embodiment of the present invention.

According to FIG. 1, a condenser (the upper body of the condenser is denoted by reference numeral 3 and the lower body of the condenser is denoted by reference numeral 4) is installed below the steam turbine 1 and has a main steam. The pipe 5 penetrates the side plate of the condenser upper body 3 from a direction perpendicular to the axis of the steam turbine 1, passes through the inside of the condenser upper body 3, passes through the connecting cylinder 2,
It connects to the turbine nozzle 6 installed in the connecting cylinder 2. In order to prevent the exhaust conditions of the turbine 1 from deteriorating, it is necessary to increase the sectional area of the connecting cylinder 2 by the sectional integral of the main steam pipe 5 included therein. Is sufficiently long with respect to the diameter of the steam turbine, so that the dimensional change of the connecting cylinder 2 necessary for enlarging the cross-sectional area is small. Space increases. FIG. 2 and FIG. 3 schematically show this. The steam turbine shown in FIGS. 2 and 3 is a mixed-pressure single-flow exhaust type steam turbine that has been widely used in recent combined cycle plants for power generation business. FIG. Reference numeral 3 denotes a second embodiment of the present invention, in which the low-pressure main steam pipe 10 of the main steam pipe is connected from the inside of the condenser upper body 3 to the nozzle of the steam turbine 1 via the connecting body 2. .

Compared with FIG. 2, the second embodiment of the present invention shown in FIG. 3 has a low-pressure main steam pipe 10 connected to the turbine nozzle from the inside of the condenser upper body 3 to provide a space around the turbine. It can be seen that has increased. in this way,
By housing the low-pressure main steam pipe 10 in the condenser upper body 3, the piping around the steam turbine can be simplified, resulting in a space allowance, and improving the efficiency and safety of construction work and maintenance work. be able to.

On the other hand, when the turbine shaft length is short, connecting all the main steam pipes from below the turbine 1 is difficult because it is difficult to secure a space because the turbine shaft length is short. The main steam pipe is connected from above the turbine or from the side of the turbine, so the main steam pipe and the main valve must be supported from the turbine installation floor, which complicates the pipe support structure. In addition, the maintenance work of the turbine becomes complicated, and the piping is routed on the turbine installation floor, so that the turbine maintenance space is narrowed and the appearance is impaired.

On the other hand, in the third embodiment of the present invention shown in FIG. 4, the low-pressure main steam pipe 10 is connected from the inside of the condenser upper body 3 to the nozzle on the steam turbine 1 side via the connecting body 2. By doing so, even when the turbine shaft length is short, the above-described problem of the related art can be solved.

When the main steam pipe penetrates the condenser, the penetrating portion must have a sufficient hermetic structure to maintain the degree of vacuum in the condenser. However, thermal expansion occurs in the steam turbine and the main steam pipe due to being heated by high-temperature steam. On the other hand, condensers are usually
Since the bottom is fixed to the concrete foundation, thermal expansion occurs towards the upper turbine side. Therefore, when the condenser penetration part of the main steam pipe is fixed, a large thermal stress is generated in the condenser penetration part and the turbine nozzle part due to the thermal expansion of the main steam pipe itself and the thermal expansion of the steam turbine and the condenser. In addition, there is a problem in strength of piping and condenser. Therefore, conventionally, in the case of a bleed pipe that takes out steam from a steam turbine, by installing an expansion joint at the outlet from the steam turbine, the effect of thermal expansion is absorbed, and the condenser side plate penetration is welded. It is fixed. However, the main steam pipe is a pipe for supplying steam to the turbine, as opposed to the bleed pipe, and therefore, if an expansion joint is used for the connection with the turbine as in the bleed pipe, the main steam pipe will collect in the expansion joint part. The drainage flows into the turbine and causes damage due to erosion or the like of the turbine blade, which is not preferable.

Therefore, in a fourth embodiment of the present invention, as shown in FIG.
A telescopic bellows 13, a sleeve 12 for inserting the bellows 13, a first support member 14 for connecting the bellows 13 to the sleeve 12, and a second support member 15 for connecting the bellows 13 to the main steam pipe 5. The expansion joint thus configured connects the condenser upper body side plate 16 and the main steam pipe 5.

According to the embodiment of the present invention shown in FIG. 5, the heat expansion of the main steam pipe 5, the steam turbine, and the condenser is absorbed by the expandable and contractable bellows 13, so that no large thermal stress is generated. . FIG. 6 shows how the bellows 13 absorbs thermal expansion.

Further, according to the embodiment of the present invention shown in FIG. 5, the sleeve 12 is welded to the condenser upper body side plate 16, and the sleeve 12, the bellows 13, and the bellows 1 are provided.
3 and the main steam pipe 5 are welded via the first and second support members 14 and 15, respectively, so that the airtightness of the condenser is not impaired.

Further, according to the embodiment of the present invention shown in FIG. 5, the expansion joint has a gap (bellows 1) formed by the main steam pipe 5, the bellows 13, and the second support member 15.
3) is open to the outside of the condenser. As shown in FIG. 7, the expansion joint may have a structure in which a gap formed by the main steam pipe 5, the bellows 13, and the second support member 15 is opened to the inside of the condenser. However, in this case, the space becomes an atmosphere in the condenser, and the drain easily accumulates, and there is a concern that corrosion may occur.
Therefore, in the embodiment of the present invention shown in FIG.
The gap formed by the bellows 13 and the second support member 15 has a structure that is open to the outside of the condenser, so that the gap is made to be in an atmosphere of the atmosphere, and the accumulation of drain is prevented.

Further, if the sleeve 12 is inclined downward toward the inside of the condenser, it is possible to prevent the drain from accumulating in the sleeve 12.

Next, FIG. 8 shows a fifth embodiment of the present invention.

In the embodiment of the present invention shown in FIG. 8, the main steam pipe 5 penetrates the side plate of the condenser upper body 3 and forms a bent portion in the condenser upper body 3, and then the turbine nozzle 6 Connected to. Accordingly, when the main steam pipe 5, the steam turbine, and the condenser thermally expand, the bent portion of the main steam pipe 5 bends to absorb the thermal expansion.

Next, FIG. 9 shows a sixth embodiment of the present invention.

In the embodiment of the present invention shown in FIG. 9, the main steam pipe 5 is supported in the condenser upper body 3 by a housing of the condenser upper body 3 in a direction perpendicular to the axis of the steam turbine. Is done. In other words, the support system limits only the thermal expansion of the main steam pipe 5 in the direction perpendicular to the steam turbine axis, and does not restrict the thermal expansion in other directions or the twisting of the main steam pipe 5 at all. This is to prevent unnecessary force or moment from being applied to the steam turbine due to thermal expansion of the main steam pipe 5 or a cold spring.

In the illustrated embodiment, the case where the main steam pipe 5 is penetrated through the side plate of the condenser and connected to the turbine nozzle 6 from inside the condenser is illustrated. When the portion is located below the lower surface of the turbine installation floor 19, the same applies when the main steam pipe 5 is passed through the side plate of the connecting cylinder 2 and connected to the turbine nozzle 6 from within the connecting cylinder 2. The effect can be obtained.

[0026]

According to the present invention, since a part of the main steam pipe is housed in the condenser, the pipe around the steam turbine can be simplified, a space margin is generated, and construction work and maintenance and inspection are performed. Work efficiency and safety can be improved.

[Brief description of the drawings]

FIG. 1 is a structural diagram showing a first embodiment of a steam turbine power plant according to the present invention.

FIG. 2 is a structural diagram of a conventional steam turbine power generation facility.

FIG. 3 is a structural view showing a second embodiment of the present invention.

FIG. 4 is a structural diagram showing a third embodiment of the present invention.

FIG. 5 is a structural diagram showing a fourth embodiment of the present invention.

FIG. 6 is an operation explanatory view of a fourth embodiment of the present invention.

FIG. 7 is a comparison diagram with the fourth embodiment of the present invention.

FIG. 8 is a structural diagram showing a fifth embodiment of the present invention.

FIG. 9 is a structural diagram showing a sixth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Steam turbine, 2 ... Connection body, 3 ... Condenser upper body, 4
... condenser lower body, 5 ... main steam pipe, 6 ... turbine nozzle, 7 ... generator, 8 ... high pressure main steam pipe, 9 ... high temperature reheat steam pipe, 10 ... low pressure main steam pipe, 11 ... low temperature reheat Steam pipe, 12 ... sleeve, 13 ... bellows, 14 ... first support member, 15 ... second support member, 16 ... condenser upper shell side plate, 17 ... turbine exhaust steam, 18 ... restrent, 1
9 ... Turbine installation floor.

Claims (6)

[Claims] 1. A steam turbine installed on a gantry, a steam generator for supplying drive steam to the steam turbine, and a condenser installed below the steam turbine and into which exhaust gas from the steam turbine flows. In the steam turbine power generation equipment provided, a main steam pipe for supplying drive steam from the steam generator to the steam turbine, a side plate of a condenser, or a side plate of a connecting body connecting the condenser and the steam turbine. A steam turbine power generation facility, wherein the steam turbine power generation facility is penetrated and connected to a turbine nozzle from inside the condenser or the connecting body. 2. The steam generator according to claim 1, wherein a through portion of the main steam pipe in the condenser side plate or the connecting body side plate connects a bellows which can be extended and contracted, a sleeve for inserting the bellows, and the bellows to the sleeve. A first support member;
A second support member for connecting the bellows to the main steam pipe; and an expansion joint for connecting an outer periphery of the sleeve to a condenser side plate penetration portion or a connection trunk side plate penetration portion, so that the condenser side plate or connection is provided. A steam turbine power generation facility wherein a body side plate and a main steam pipe are connected. 3. The expansion joint according to claim 2, wherein a gap formed by the main steam pipe, the bellows, and the second support member is open to the outside of the condenser or the outside of the connecting barrel. Steam turbine power generation equipment. 4. The steam according to claim 2, wherein the sleeve is connected to the condenser side plate or the connection shell side plate with a downward slope toward the inside of the condenser or the inside of the connection shell. Turbine power generation equipment. 5. The method according to claim 1, wherein:
A steam turbine power generator, wherein the main steam pipe penetrates a condenser side plate or a connecting shell side plate from a substantially horizontal direction, forms a bent portion in the condenser or the connecting shell, and then connects to a turbine nozzle. Facility. 6. The method according to claim 1, wherein:
A steam turbine power generation facility, wherein a main steam pipe is supported in a condenser or a connecting body by a restrent that restricts movement of the steam turbine in a direction substantially perpendicular to the axis.