JPS6060002B2 - Pressure regulator for marine turbine generator steam supply system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a pressure regulating device for a marine turbine generator steam supply system configured to use the steam of the marine turbine generator for purposes other than power generation.

[Conventional technology]

Utility Model 11890, 1984, as power generation equipment for ships
A structure as shown in Publication No. 1 and FIG. 1 was devised.

In addition to being driven by the steam turbine T, the generator G is also driven in a shaft-driven manner by a diesel main engine E, either in addition to or in addition to this. Further, when the turbine output exceeds the generator load, a part of the turbine output drives the fixed pitch propeller F. The steam supply system S includes a steam generator 5
A steam supply pipe 52 is connected from the steam generator 1 to the steam turbine T, but this steam generator 51 is connected to equipment other than power generation equipment, such as a miscellaneous steam supply pipe as a second steam supply pipe to a main engine fuel oil heater. 53 are connected. Since the steam turbine T is connected to the main engine E via a clutch D and a speed reducer B, its speed is determined by the speed of the main engine, so although the speed governor function is lost, it is possible to maintain steam without leaving any steam. For use, the speed governor is set higher than the rotation equivalent to the main engine rotation so that the steam control valve is fully open. [
[Problems to be Solved by the Invention] In such a control state, when the main engine pressure is sufficient, that is, when the exhaust gas economizer 1M is generating enough steam to balance the steam demand of the steam supply system, Miscellaneous steam supply pipe S
3, when the steam demand decreases, the steam pressure in the steam supply system S increases, and as a result, the steam pressure at the inlet of the steam turbine, which is in the above-mentioned control state, exceeds its maximum allowable steam pressure, and the steam pressure at the inlet of the steam turbine increases. The amount of steam flowing in from the tank also increases.

Therefore, the driving torque becomes an excessive torque that cannot be tolerated by the drive system including the steam turbine, and its safety is threatened. The above situation also occurs when the brackish water separation drum 1A is shared with the brackish water separation drum of an auxiliary boiler having a high rated pressure, and when the boiler is used or used together with an exhaust gas economizer.

The above-mentioned steam supply system has not only the disadvantages caused by the increase in vapor pressure as described above, but also the disadvantages caused by the decrease in vapor pressure as described below. This decrease in steam pressure occurs under the control conditions described above, regardless of the output of the main engine E, if the amount of steam generated by the exhaust gas economizer 1M is less than the overall amount of steam required by the miscellaneous steam demand equipment and the steam turbine. Each vapor pressure is lower than the required vapor pressure. In this case, the lack of energy on the steam turbine side is supplied from the main engine E, so there is no problem, but the operation of miscellaneous steam demand equipment is hindered. In FIG. 1, A is a joint, B is a speed reduction device, C is a speed increase device, D is a clutch, F is a propeller, and B is a boiler water circulation pump.

Furthermore, even in the conventional example shown in Japanese Utility Model Application Publication No. 54-118901, no pressure adjustment mechanism is provided in the steam passage connecting the exhaust gas boiler, which is the steam generator, to the steam turbine. Similar to the example of the device shown in Figure 2, there is a risk that excessive torque will be generated in the steam turbine system.

In addition, in the conventional example shown in this publication, if steam with a pressure lower than the required pressure flows into the miscellaneous steam vibrator, the pressure control valve shuts off the flow, which prevents the operation of the subsequent miscellaneous steam demand equipment. This will cause trouble.

[Purpose of the invention]

The present invention was devised to solve the problems that occur in marine power generators or similar systems as described above, and its purpose is to ensure that the operation of miscellaneous steam demand equipment is not hindered even if fluctuations occur in the main engine output. It is an object of the present invention to provide a pressure regulating device for a steam supply system of a marine turbine generator, which can prevent excessive torque from occurring in a drive system such as a steam turbine.

[Summary of the Invention] In order to achieve the above object, the present invention provides a secondary pressure regulator in a steam supply pipe communicating from a steam generator to a steam turbine to suppress the steam pressure to below the maximum steam pressure allowable in the steam turbine. The minimum pressure in the miscellaneous steam supply pipe and the maximum pressure in the steam supply pipe can be adjusted by constructing a valve and a primary pressure regulating valve that maintains the steam pressure above the minimum steam pressure required by the miscellaneous steam demand equipment, respectively. The main point is to ensure that the limit is not exceeded.

Here, the primary pressure means the steam pressure generated by the steam generator (exhaust gas economizer), and steam at approximately the same pressure flows into the miscellaneous steam supply pipe.

The secondary pressure refers to the pressure of steam flowing into the steam turbine, and is smaller than the primary pressure by the pressure loss of the valve. EXAMPLE Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

FIG. 2 shows the configuration of a marine power generator used on a ship.

The generator G of this turbine generator is rotated by a steam turbine T driven by steam supplied from a steam supply system S, and in addition or in addition to this, the generator G is also rotated by a diesel main engine E.
It is rotated in a shaft-driven power generation format via a single joint S1 speed reducer B, multi-stage switching speed increase device C, and clutch D. Further, when the output of the steam turbine is sufficient, the steam turbine T also drives the fixed pitch propeller F in addition to the generator. The steam supply system S of the steam turbine configured as described above is connected from the steam generator S1 to the steam turbine T via the steam supply pipe S2, and from the steam generator S1 to the miscellaneous steam supply pipe S3 via the miscellaneous steam supply pipe S3. It is configured to be in communication with equipment 0, and supplies a portion of the generated steam to the miscellaneous steam supply pipe, while supplying the remaining steam to the steam supply pipe. In the steam supply pipe S2 of the steam supply system, a primary pressure regulation valve V1 and a secondary pressure regulation valve V2 are interposed in parallel, and the pressure regulation device 1 for a marine turbine generator steam supply system of the present invention
is mainly composed of The primary pressure regulating valve V1 is controlled by picking up the pressure on the upstream side of this valve, that is, the exhaust gas economizer side, and the secondary pressure regulating valve 2 is controlled by picking up the pressure on the downstream side of this valve, that is, the inflow side to the steam turbine T. be done. V3 and V4 are switching source valves connected in series to valve 1 and valve V2, respectively. The steam generator S1 includes an exhaust gas economizer 1M and an auxiliary boiler 1A, and the first heat exchange section M1 of the exhaust gas economizer 1M and the evaporation section As of the auxiliary boiler 1A are communicated with the steam supply pipe S2.

The inflow side of the second heat exchange section Ms of the exhaust gas economizer 1M is communicated with the water supply section of the auxiliary boiler 1A via the boiler water circulation pump P, and the outflow side thereof is connected to the evaporation section M of the auxiliary boiler 1A.
is connected to. Therefore, the steam generated in the economizer 1A flows toward the miscellaneous steam supply pipe S3 and the steam supply pipe S2 at that pressure state, but the steam generated in the steam turbine T is lowered by the pressure loss at the control valves Vl and V2. Pressure steam will flow in.

In addition, the steam turbine T is provided with a speed governor T1, to which a clutch D is fitted.In other words, the exhaust gas heat amount of the main engine E is utilized, and at the same time, the speed governor T1 is connected to the speed governor T1. When a shaft-driven generator or propeller-driven type with a wide main engine output range is used, the turbine steam control valve controlled by speed governor T1 is set at its highest setting, fully open, and the generator and steam The rotational speed of the turbine is determined by the speed of the main diesel engine E.

In addition, if the allowable rotational speed of the shaft-driven generator cannot be maintained even after switching the multi-stage speed increaser C, the clutch D is disengaged and the thermal output of the main engine E is reduced. The steam supply system is configured to use the auxiliary boiler 1A in combination to make up for the shortage.

Next, the operation of the device of the present invention will be explained. When the ship is on normal voyage, that is, when its main diesel engine E is operated at normal output (output within the range set for its high efficiency), switching main valve V3 is opened (switching User valve■
4 is closed), the primary pressure regulating valve 1 is adjusted to its fully open position, and the clutch D is engaged, so that the generator G is connected to the steam turbine T in order to utilize the sufficient exhaust heat of the main engine. However, if the rotational power of the steam turbine T, which rotates the generator G in this way, becomes insufficient, the shortage is made up for by multi-stage switching to maintain the allowable rotation speed of the generator G. From the main engine E while changing the speed reduction gear C?
The signal is transmitted to the rotating shaft of the generator G via the B1 multi-stage switching speed increasing device C1 and the clutch D.

Conversely, if the turbine output exceeds the generator load, D,
Propeller F is driven via C and B. At this time, the steam flow rate and steam pressure (primary steam pressure) maintain an equilibrium state at the intersection of the A-A curve and the α-α curve in Figure 3, that is, point a.
The steam pressure at this time is higher than the minimum steam pressure P1 required for miscellaneous steam demand equipment.

The A-A curve in FIG. 3 is the steam flow rate vs. steam pressure curve of the steam supply system S in the operating state as described above, that is, in the state where the clutch D is engaged and the turbine steam control valve is fully open, and α
The 1α curve is the steam amount vs. steam pressure curve of the exhaust gas economizer 1M during normal output of the diesel main engine. Then, as described above, steam flows into the miscellaneous steam supply pipe S3 at approximately the same pressure as the steam generated by the economizer 1M. Under the operating conditions described above, assuming that the output of the main diesel engine E decreases to an extent corresponding to the β-β curve and other operating conditions remain unchanged, the steam pressure in the steam supply system S reaches equilibrium at point b. reach

In this equilibrium state, steam having the minimum steam pressure P1 required by the miscellaneous steam demand equipment 0 cannot be supplied to the miscellaneous steam demand equipment 0. When the steam pressure of the steam supply system S decreases below the minimum steam pressure P1, the primary pressure regulating valve V1, which was previously fully open or at a predetermined valve opening, operates to reduce its valve opening. .

Thereby, the steam flow rate vs. steam pressure curve shown by the steam supply system S shifts to the BB curve. Thus, the steam pressure of the steam supply system S is the minimum steam pressure P1 required by the miscellaneous steam demand equipment 0.
(point C). The degree of decrease in main engine output is β″-β
``curve'' or the β''-β'' curve, the primary pressure regulating valve ■1 is adjusted accordingly, causing a shift in the steam flow rate vs. steam pressure curve indicated by the steam supply system S. to maintain the steam pressure of the steam supply system S at P1 (C in Fig. 3).
″ and C″).

Such adjustment occurs as shown by the dotted line in FIG. 3, and the steam pressure of the steam supply system S is maintained above P1.

The explanation up to this point has been based on the case of a decrease in the main engine output, but now let's assume that the main engine output remains unchanged and the steam consumption of miscellaneous steam demand equipment decreases.

In this case, the switching valve (4) is opened. In this case, the steam flow rate vs. steam pressure curve exhibited by the exhaust gas economizer 1M does not change as an α-α curve because the main engine output is constant, but the steam flow rate vs. steam pressure curve of the steam supply system S shifts toward the C-C curve. .

Here, the C-C curve shows the characteristics when the demand for steam from the miscellaneous steam equipment decreases (the secondary pressure control valve is fully open). Therefore, if the degree of reduction in steam consumption of miscellaneous steam demand equipment is as expressed by the C-C machine curve in Figure 3, then
The steam pressure (secondary steam pressure) of the steam supply system S is balanced at point d, and the steam pressure supplied to the steam turbine T is balanced at point X in FIG.

Here, the DD curve shows a steam flow rate-steam pressure (secondary pressure) curve of the steam turbine T. This steam pressure (secondary steam pressure) exceeds the maximum steam pressure (maximum turbine inlet pressure) P2 determined by the mechanical strength of the drive mechanical system including the steam turbine T. When the steam pressure at the inlet of the steam turbine T exceeds the maximum steam pressure, the secondary pressure regulating valve 2, which was previously fully open or at a predetermined valve opening, operates to reduce its valve opening.

The steam pressure in the steam supply system S is shifted by the decrease in the opening degree of the valve V2, resulting in a curve E in Figure 4 (the relationship between the primary steam pressure and the steam flow rate when the secondary pressure control valve is closed). Equilibrium is reached at the intersection y of the α-α curve, and the steam pressure of the steam turbine T is lower than the pressure Py at this y point.
The maximum steam pressure P2 is lower by the steam loss [Py-Pz] (Py is the steam pressure at point y, Pz is the steam pressure at point z), and an excessive flow rate does not flow into the steam turbine T. Therefore, the safety of the rotating system is maintained without causing the turbine T to generate excessive torque. Furthermore, at this time, the pressure Py
is the pressure of steam flowing into the miscellaneous steam supply pipe S3.

Such supercharging of the amount of steam to the steam turbine T occurs not only when consumption decreases in miscellaneous steam demand equipment, but also in the following cases.

In addition to being used for power generation assistance, when the auxiliary wheel 1A, which has a high rated pressure and is used for a specific purpose such as replenishing inert gas in a tanker, is used by joining the steam supply system S for that specific purpose, Problems similar to those described above arise.

The steam pressure that increases in such a case is also controlled by the secondary pressure control valve V2.
By narrowing down the steam flow rate vs. steam pressure characteristic (curve) exhibited by the steam supply system S from the upper side to the lower side as shown in FIG. 4, the pressure loss [Pt-
Pz] to lower the steam pressure at the steam turbine inlet to the maximum allowable steam pressure P2. here,
In the figure, steam pressure P3 indicates the rated steam pressure of the auxiliary wheeler,
The F-F curve shows the primary steam pressure and steam flow rate characteristics with the secondary pressure control valve throttled.

Further, Pz indicates the vapor pressure P2 at the Z point. in this way,
Maximum steam pressure P allowed for steam pressure at the steam turbine inlet
2, it is possible to solve the problem on the steam turbine side caused by the pressure increase when the steam supply system S is used for the above-mentioned specific purpose in combination with the auxiliary boiler 1A. In the above embodiment, the case where the primary pressure control valve and the secondary pressure control valve are provided in parallel in the above supply pipe has been explained, but even if both these valves are interposed in series in the steam supply pipe, the same effect as in the above embodiment is obtained. You can obtain the following effects.
[Effects of the Invention] As is clear from the above explanation, according to the present invention, when steam generated by exhaust heat is used for purposes other than power generation, even if the consumption amount fluctuates, the steam turbine The pressure of the inflowing steam can be suppressed to a certain value or less, thereby preventing excessive torque from being generated in the drive mechanical system including the steam turbine, and improving the safety of this system.

Even if an auxiliary boiler with a pressure higher than the maximum steam pressure of the steam turbine is used in combination with the two-steam generator, the steam turbine side can be protected from the high steam pressure.

3 Even if the output of the diesel main engine decreases, the steam supply pressure to miscellaneous steam demand equipment used for purposes other than power generation can be maintained above the required constant value, and the operation of this installation will not be hindered. do not have.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the configuration of the aforementioned marine power generation equipment, Figure 2 is a diagram showing the configuration of the marine power generation equipment in which the present invention is implemented, and Figure 3 is a diagram showing the steam flow rate vs. steam pressure curve of the steam supply system. Figure 4 shows the generated steam amount vs. steam pressure curve of the auxiliary boiler, the steam flow vs. steam pressure curve of the steam turbine and pressure regulator, and the steam flow rate of the exhaust gas economizer. It is a figure showing one vapor pressure curve superimposed. In the figure, 1 is the pressure regulator of the marine turbine generator steam supply system, S is the steam supply system, S1 is the steam generator, S2 is the steam supply pipe, S3 is the miscellaneous steam supply pipe, and ■1 is the primary pressure regulating valve. ,
V2 is a secondary pressure regulating valve.

Claims (1)

[Claims] 1. Sensible heat from high-temperature exhaust gas discharged from the main diesel engine is recovered in a steam generator to generate steam, and a portion of the generated steam is supplied to miscellaneous steam demand equipment via the miscellaneous steam supply pipe, while the remaining In a pressure regulator for a marine turbine generator steam supply system that supplies steam to a steam turbine for power generation through a steam supply pipe, the steam flowing into the miscellaneous steam supply pipe is connected to the steam supply pipe. A primary pressure control valve that maintains the pressure above the minimum steam pressure required by the miscellaneous steam demand equipment, and a pressure of the steam flowing into the steam turbine by the mechanical strength of the drive mechanical system including the steam turbine. A pressure regulating device for a steam supply system of a marine turbine generator, characterized in that a secondary pressure regulating valve is provided to maintain the steam pressure below a predetermined maximum steam pressure.