JPS58196376A - System for opening quickly valve - Google Patents

Abstract

PURPOSE:To reduce the number of regulating valves and restrain fluctuation of flow by closing the opened regulating valve in the supply of flow path changing-over signal while opening the closed regulating valve to the opening corresponding to fluid flow. CONSTITUTION:When abnormality signal SDb is supplied to a turbine stop circuit 17b, signal S3b of L level and signal S4b of H level are respectively generated from this circuit. When the signal S3b is generated, a regulating valve 6b is closed. On the other hand, when the signal S4b is generated, said valve is opened to the opening corresponding to vapor flow in a pipe path 24 right before abnormality signal SDb is generated, so that the vapor in the pipe path 24 is discharged to the atmosphere througha regulating valve 33. Thus, the fluctuation of flow is minimized even if the flow path changing-over signal is generated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a quick-opening valve system that rapidly switches an R-body flow path with less variation in flow rate.

Figure 1 is a block diagram showing an example of the configuration of a conventional quick-open valve system.The configuration, operation, and purpose of this system will be explained below. In FIG.

Reference numeral 1 denotes a boiler, and the high pressure steam generated and drawn by the boiler 1 is supplied to the turbine 4a through pipes W&2 and 3. Steam is supplied from the pipe 182 to the O turbine other than the turbine 4a.In the pipe line 3 leading to the turbine 4aK, there is a differential pressure detector 5a that detects the flow rate of high pressure steam flowing through the O pipe line 3. was inserted. An <a joint 6a is inserted between the differential pressure detector 5a and the turbine 4a. 't, the differential pressure detector Sm of the pipe line 3 and the control valve 6a
Pipe line 1 is branched from between O and the other end of this O pipe%70 is connected to the high pressure steam header HcI! A control valve 10a and a control valve l1m are inserted into this conduit 7, respectively. The control valve 10m is an on-off valve, the control valve 11a is a flow control valve, and the flow rate is determined by the control valve 11m.

The flow rate of high-pressure steam detected by the above-mentioned differential pressure detector 5aK is converted into an electric signal 8 by the transmitter 13aK, and is supplied to the flow rate manual control device 14a. R14a is the output signal 811 of the transmitter 13a
The display part and the valve opening f to display the flow rate of high pressure steam based on
The signal S2. corresponds to the setting value of the valve opening setting knob of WI & fixed knob. The signal output section outputs the signal 521L, and the signal 521L is transmitted to the electropneumatic converter 15 &
supplied to The electro-pneumatic converter @15m converts the signal S21 into a pneumatic signal, and the mourning pressure signal output from this electro-pneumatic converter lB15m is supplied to the control valve 11m.
Than.

The control valve 11a is opened at a valve opening corresponding to the signal S21.

In the front, reference numeral 17m is a turbine stop circuit.

This turbine stoppage - 11117a is caused by a turbine abnormality such as a failure of turbine 4&, a drop in the pressure and temperature of steam supplied to turbine 4a below the allowable limit, and a vacuum level below 18 m for condensate cooling. It controls the opening and closing of the joint valve 61°10m based on the abnormal signal 5Dal supplied when the
are respectively converted into pneumatic signals by electropneumatic converters a@4g 19a #20aK and supplied to the joint valves 6a and 10a.

Therefore, the above-mentioned components 5a, 6a, 1eas11
a*13a, 14m, 15as17a, 19a*! Oa
Therefore, quick-open valve system No. 22 is configured to switch the high-pressure steam om* supplied to the turbine 4a.

Next, a part of the steam that passed through the turbine/4m was supplied to the high-pressure steam header 9, which is a header for supplying high-pressure steam to chemical plants and the like. The other part is low pressure steam header 2
3, and the other part is a 18m cooler for condensate.
supplied to Also.

The steam in the low pressure steam header 23 is supplied to a chemical plant or the like, and is also supplied to the turbine 4b through pipes 24 and 25, and is also discharged to the atmosphere through a pipe @26.

Here, the reference numeral 22b indicates a quick-opening valve system that switches the flow path of steam supplied to the turbine 4b, and the quick-opening valve system 22b) is the quick-opening valve system 22m described above except for the dimensions of the equipment. Each component Sb, 6b... 20b is exactly the same as the configuration of the quick-open valve system 22m, and each component Sb, 6b... 20b is respectively 5m, 6m... 20m of the quick-open valve system 22m.
It corresponds to Control valve IQb is an on-off valve, tpy control valve 1
1b is a variable rate control valve, and the flow rate O is controlled by the control valve 11b.
It is also the same. However, abnormal signal 5DbF'i
An abnormality occurred in turbine 4bK and the meeting was held in the ninth place.

It is supplied to the turbine stop circuit 17b.

Next, a part of the quick-open valve system 22b will be explained.

First, when the turbine 4b is operating normally, the H level signal S from the turbine stop-W&17b
, b to electro-pneumatic conversion l1119b, L level signal S4b
are respectively output to the electropneumatic converter 20b. This result b
W4 section valve 6b is in closed state 1tb sea bream section valve 10b is in closed state @. In this state, the operator operates the flow rate manual control device [14b
The flow rate of steam flowing through the pipe line 24 is detected by the display part of the control valve 11b. %24. However, since the 1111 node valve 10b is closed, steam does not flow in this direction and is supplied to the turbine 4b.

Next, some abnormality occurs in the turbine 4b.

When the abnormal signal SD is supplied to the turbine stop-%17b, the turbine stop-w117b becomes the L level O signal S.
h and H level (DM number b4h is output to 3. As a result, the joint valves 6b and 10b are closed and opened, respectively, and the p1 pipe 24 (D steam is stopped in the direction of the turbine 4b). , is released into the atmosphere through the control valve 1 (1, 11b).
Since the valve 1i & of the turbine 4b is set to 0, the flow rate of steam in the sieve 24 is secured by the flow rate that was in the turbine 4b'ICR.

In addition, the operator can perform the control valve Bbo extension-foli1m by using the flow manual control 111114bo intermediary direct setting knob.

This quick-open valve system prevents damage by preventing the abnormality from affecting other turbines, even if a problem occurs in a certain turbine and that turbine has to be disconnected from the system. It is intended to erupt to a minimum. If an abnormality occurs in the turbine 4b and it is disconnected 1i1
．． As the amount of steam flowing through the pipe line 24 suddenly decreases, the amount of steam extracted from the turbine 4 also decreases rapidly, causing the turbine 4a to become inoperable and having to stop the turbine 4a. Therefore, the entire chemical factory etc. will be shut down. Therefore, if an abnormality occurs in the turbine 4b and the turbine 4b is disconnected, the pipe line 26 is opened at the same time by the quick-open valve system, and the pipe line 26 is
The goal is to secure 4 steam warehouses. This flow rate v4m is determined by the control valve 11b in the case of the turbine 4b, and by the control valve 11m in the case of the turbine 4.

Such a system is often used not only in boiler and turbine plants but also in chemical plants and other processes where a 41I bypass line is provided.

The above is the configuration, operation, and purpose of the conventional quick-open valve system. By the way, the above-mentioned conventional quick-open valve system includes control valves 10 m and 10 for opening and closing in the pipes 7 and 26.
b and a control valve 11a for adjusting the flow rate v4.

11b must be provided respectively, which has the drawback of increasing the price. This drawback is particularly noticeable when a large-diameter control valve that is resistant to high pressure and heat is used, as in the above-mentioned boiler and turbine plant shutdowns.

Therefore, the present invention provides a quick-opening valve system that can reduce the number of control valves.Each RII is provided with one control valve, and a flow section switching signal (for example, an abnormal signal in Fig. 111) is provided. 8D, , 5Db) are supplied, the control valves that have been in the open state are opened, and the control valves corresponding to the #1 amount of fluid are set to the closed state in step I11. It is a good idea to leave it in the open state.

An embodiment of the present invention will be described below with reference to one drawing.

Bait 2 figure is 1 quick opening valve system 30 by 01Il Ming.
12 is a diagram showing a case where the opening valve system 22b is used in place of the opening valve system 22b shown in FIG. 11. 1, ζ (% in Di!gl)
The same reference numerals are given to the parts corresponding to each part of l11111I, and the explanation thereof will be omitted. In the quick-open valve system 3O in line 2111, the turbine stop circuit 1? b output signal 88. is supplied to the electro-pneumatic converter 1119b, and the output signal ') 84b is supplied to the turbine stop control circuit 31 and the three-way valve 32, respectively. Turbine stop control time I! 31
is the ninth control valve 33 inserted into the pipe II2 (1 m@t), and the output signal 85 is supplied to the electro-pneumatic converter 34. !
For details on 31, please visit IIKI! l! do. The electro-pneumatic converter 34 converts the signal S6 into a pneumatic signal and supplies it to the inlet 32 of the three-way valve 32.

3 way valve 3! is the signal 84. which increases the output from the turbine stop gi*xyb. The flow path is switched by K, and
When the signal S4b is at H level O, the air pressure signal supplied to the inlet port 33m is conducted to the outlet port sxmvc.

The control valve 33 opens at an opening that matches the air pressure signal, and when the signal 84b is at the L level, it is supplied to the inlet 3zm. 32C becomes conductive and the % control valve 3s closes.

Next, we will discuss the details of the first turbine stop control 1111SIK. Figure 3 is a block diagram showing the configuration of the turbine stop control circuit 310. In ζ011, mark 4 #36 is IE
! Transmitter 13-〇 output signal 8□ indicating rlAK, Toh in the square root calculation circuit that calculates the O square root.

Signal 88. This is converted into a value by the dot square machine calculation circuit W&36, which results in a signal S6 which changes linearly with respect to changes in the steam flow rate in the pipe 240, and is sent to the calculation circuit 1137 as a gravity field. The three arithmetic circuits signal the opening of the control valve 330 corresponding to the steam flow rate of the pipe line 24.
The calculation result is outputted to the current/voltage converter 38 as a current signal. The current/voltage converter 3S converts the tfall signal supplied from the arithmetic path 37 into a voltage signal 8. Convert and output. Output voltage signal S
8 is supplied to one end of relay contact 39.

Relay contact 39 receives signal 8. output from turbine stop 111117b. , K, and when the signal S4b is at the L level, it is in the closed state, and the signal S4 is in the closed state.
When b goes to H level, it becomes open. This relay contact 3
The other end of 9 is connected to the terminal & of the manual changeover switch 40. The manual changeover switch 40 automatically controls the control valve 33.
This is a switch that switches between control and manual control.
Its terminal is connected to the positive voltage terminal of the DC power supply 42 via the manual changeover switch 41 and connected to the negative voltage terminal of the DC power supply 44C through the manual changeover switch 43, and its common terminal C is capacitor 45 and gain 1
It is connected to the input terminal of a hold circuit 1347 consisting of an amplifier 46. Hold circuit *47 holds the signal (voltage signal 1, and converts this held signal into voltage/current conversion 1
) feed to 4g. The voltage/current converter 64g converts the output signal of the hold circuit 1147 into a current signal Ss, and supplies it to the electro-pneumatic converter 34 shown in FIG.

Next, the operation of the quick-open valve system 30 having the above configuration will be explained. In the following explanation, changeover switch 4
It is assumed that common terminal C of 0 and terminal 1 are connected. However, when the turbine 4b is operating normally, the turbine stops as described above. 117Th
A signal 8□ at an H level and a signal 84b at an L level are outputted from the terminal.

As a result, when the control valve 6b is opened, the tDh pipe 240 steam is supplied to the turbine 4b, and the air pressure signal output from the electro-pneumatic converter 34 is blocked by the three-way valve 32, and the air pressure signal is applied to the control valve. becomes atmospheric pressure, and the control valve 33 closes.Furthermore, the relay contact 39 shown in Figure 3 closes, and therefore.

The value of the output signal S8 of the voltage/current converter 38 is held in the hold circuit 4F.

Next, when some abnormality occurs in the turbine 4b and the abnormality signal 8D is supplied to the turbine stop circuit 17b, the turbine stop circuit 17b outputs an L level signal S3b and an H level signal S4b, respectively. Turbine stop time $17b or I, L level signal S3. When is output, the Ij1 node valve 6b becomes closed. On the other hand, turbine stoppage 1i! When the H level signal S4b is output from t17b, the relay contact 39 becomes open. At this time, the hold circuit W&47 holds the wM of the signal S8 (hereinafter referred to as voltage V) just before the abnormal signal SDb is output, and therefore the voltage V continues to be the voltage / It is output to the current converter 48. The voltage/current &amp; divider 48 converts the electric power EEV into a source signal S5 and converts it into electric power.
! Output to 34. As a result, a 9-atm pressure signal corresponding to the voltage vVc is output from the electro-pneumatic converter 34 and supplied to the inlet 32A of the 3-way valve 32. and.

Since the signal S4b is at the H level at this point, this air pressure signal is output from the outlet 32B of the three-way valve 32 and supplied to the piI'l valve 33. As a result, the control valve 3
3 is the valve 1 corresponding to the voltage v6c.

The valve opening 1 corresponding to the flow rate of the directly connected pipe 12r24 to which the abnormal signal SD is output is opened, and the steam in the pipe line 24 is discharged into the atmosphere via the cutting valve 331. Opening the relay contact 39 at the same time as an abnormality in the turbine picks up the steam*tq) fluctuation when the g* regulating valve 6b closes, and the regulating valve 33
t) is the preferred method for setting the opening degree.

Note that when the signal S4b is at H level and the common terminal C of the manual changeover switch 40 is connected to the terminal S, and the manual changeover switch 41 is pressed, the hold circuit 47Ki1 is activated.
The positive WEE of the m power supply 42 is maintained.

As a result, when the havb valve 33 is in the open state, when the manual changeover switch 43 is pressed, the negative voltage of the DC power supply 44 is held in the hold circuit 47, and as a result, the control valve 33 is in the closed state. The opening degree can be adjusted manually. After the abnormal signal SD is generated, the control valve 33 is opened, and then the output signal S6 of the square root calculation circuit 36 or the elementary signal S2. The switching circuit may be configured to supply the output of the PID regulator to the PID regulator and the output of the PID regulator to the electro-pneumatic converter@34.
b, 33 is equipped with a positioner when speed and high customer volume are required. The control valve 33 is preferable because the relationship between the valve stem stroke and the flow rate is close to linear, and does not require complicated calculations compared to the calculation circuit 11337 using a so-called parallel valve, for example.

As explained above, according to the present invention, one control valve is provided for each fluid flow rate, and a flow path switching signal (abnormal signal 5Db in the above-mentioned embodiment) is supplied. While the control valve that was in the open state in IT is made into a closed sieve,
Since the 9 control valves that have been in the closed state are now opened with the valve opening 1 corresponding to the flow rate of the fluid, the number of V4 mode valves can be reduced, and as a result, @,! 1i! ! Cheap valve system <5 Fllt.

You get the benefits you get. ! Since the valve corresponding to the flow rate immediately before the flow path switching signal is opened immediately, even if flow path switching No. 1 is issued, fluctuations in flow rate are minimized. You can get commercials.

[Brief explanation of the drawing]

Figure 1 is a plotter diagram showing the configuration of a conventional quick-open valve system. Figure 2 is a block diagram showing the configuration of an embodiment of the present invention. Figure 3 shows the configuration of the turbine control circuit 31 in the same example. FIG. 6b, 33... control valve, 31... turbine control circuit.

Claims (1)

[Claims] In a quick-open valve system that rapidly switches fluid flows W&, one 4rk control valve is provided for each flow*, and from time 9 onwards when a flow path switching signal is supplied, the control valves that have been in the open state 11 until t are closed. A quick-opening valve system characterized in that, while the nine control valves which have been in the closed state are brought into the open state at a valve opening corresponding to the flow rate of the fluid.