JPS62121806A - Flow rate adjusting mechanism for steam turbine governor - Google Patents

Abstract

PURPOSE:To increase a valve full-open point and reduce a throttle loss of a valve as well as to aim at improvement in turbine efficiency, by constituting a governor in a way of combining it with such a valve that is different in size in a geometrical series manner. CONSTITUTION:A governor is constituted of plural valves converting size of the governor into geometrical series times. For example, in case of a four-valve type, size of each valve should be set to 1:2:4:8. With this constitution, a valve full-open point comes to 15 in number, whereby prenty of valve full-open points by far much more than valve numbers can be made possible so that a throttle loss of each valve is reduced and, what is more, turbine efficiency is improvable.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is used in the technical field of improving turbine efficiency by increasing or decreasing the flow rate of gas or liquid, which is the energy medium of a prime mover such as a steam turbine, with minimum pressure loss. be done.

Conventional technology In the conventional technology, when increasing or decreasing the flow rate using several control valves, the valves are operated according to a predetermined opening/closing order.
Therefore, the number of points at which the regulating valves are fully open at the full flow rate of the regulating valve group is the same as the total number of valves.

Therefore, throttling loss between the control valves and the control valves is unavoidable, and the loss (in the case of a prime mover, efficiency decrease) during this period is relatively large.

Problems to be Solved by the Invention The present invention aims to increase or decrease the flow rate or pressure with minimum throttling loss, eliminate the reduction in efficiency of the conventional prime mover, and realize high efficiency of the prime mover.

Means for Solving the Problems The present invention takes the following measures in order to solve the above-mentioned problems. In other words, a control valve group consisting of a plurality of control valves that increase or decrease the flow rate, including valves of geometrically different sizes, and a valve full-opening point that minimizes throttling loss of the control valve over the entire flow rate. In order to increase the number of valves, we select different combinations of valves depending on the flow rate.
The flow rate increase/decrease mechanism is used as a control device to change the flow rate to the next combination.

According to the above-described means, it is possible to have a valve fully open point that is far greater than the number of valves over the entire flow rate of the control valve group (the maximum number of fully open points is the sum of the number of classes), By combining the full-open points of each valve to increase or decrease the flow rate, so-called full-open valve control, the efficiency of the turbine can be increased by minimizing the throttling loss of the valves.

Embodiment Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 9.

FIG. 1 is a system diagram showing one embodiment of the present invention, and the reference numeral A in the figure is
are the prime mover (turbine 10) and the driven machine 15, B is the control section, C is the flow rate adjustment section and the adjustment valve 5, and the actuating section is the adjustment valve 5 and an operation section (not shown, such as a servo motor) that controls the adjustment. The valves 5 are, for example, valves V□, v2, v3, v4 with different capacities.
, v5.

The size of the valve is as follows: 1.2.4.8.16 (, when the valve size is geometrical series and the operating valve is continuous, 1.2.4.
4...etc.

The order of opening and closing of the control valves 5 to increase or decrease the flow rate is constant (9 ports) (in order of the total capacity of the control valves 5 to be operated, and the valve throttle loss is minimized when the most valves are fully open or when the required flow rate is reached). Operate each valve to create a combination of valves.

When the size of the regulating valve 5 is multiplied by a geometric series, 1 (valve size), 2.4.8.16... The total flow rate is 31, and the valve full opening point is also 31 points.

When the size of the control valve is set to continuous valve operation (1 and 4 are placed next to each other), 1.2.4.4,4・e・Total flow rate is 15
The valve full-open point is also set to 15 points.

In addition, 1.2.4.8.8・Fist・The total flow rate is 23, and the valve full open point is also 23 points.

Figures 2 and 3 show the nozzle distribution rows for a 4-valve type when the nozzle is multiplied by a geometric series, and Figures 4 and 5 show the nozzle distribution array for a 5-valve type when the nozzle is multiplied by a geometric series. Figures 6, 7, 8, and 9 show examples of nozzle distribution for two six valves.

Effects of the Invention According to the mechanism of the present invention, in regulating valve control of flow rate to a prime mover, etc., it is possible to fully open control of a far greater number of regulating valves than the number of valves over the entire flow rate. Therefore, the flow rate increases or decreases with significantly reduced valve throttling losses over the entire flow rate. Therefore, the efficiency of the prime mover increases accordingly, and when applied to other flow rate increases and decreases, minimizing pressure loss in the line can contribute to improving turbine efficiency and saving energy. Although it varies depending on the flow rate, there is an efficiency increase of about 5% or more.

[Brief explanation of drawings]

Fig. 1 is a system diagram showing an embodiment of the present invention, Figs. 2 and 3 are schematic diagrams showing an example of the distribution of 4-valve nozzles, and Figs. 4 and 5 are examples of the distribution of 5-valve nozzles. FIG. 6, FIG. 7, FIG. 8, and FIG. 9 are schematic diagrams each showing an example of distribution of six-valve nozzles. A... Prime mover and 5 driven machines, B... Control unit, C... Flow rate adjusting unit and regulating valve, 5... Adjusting valve, lO... Turbine (prime mover), 15... Driven machine 1 (generator) ). s7 figure 2 figure 113 figure 4 figure 5 figure 6 figure 7 figure 186 figure w'9 figure

Claims (1)

[Claims] A control valve group consisting of a plurality of control valves that increase or decrease the flow rate, including valves of geometrically different sizes, and a number of fully open points of the control valves that minimize the throttling loss of the control valves over the entire flow rate. To achieve this, we select different valve combinations depending on the flow rate.
The flow rate increase/decrease mechanism of the steam turbine regulator serves as a control device that changes the flow rate to the next combination.