JPS62175502A - Feedwater heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a feedwater heater for power generation equipment, and in particular, to a method for greatly alleviating restrictions on the arrangement of instrumentation equipment attached to the feedwater heater. The present invention relates to the structure of a suitable feed water heater.

[Conventional technology]

In conventional feedwater heaters, improvements have been made to the structure and materials for the internal flow of the equipment, but the structure of the instrumentation seat itself has not been discussed.

Furthermore, many applications have been filed regarding instrumentation systems, such as the one disclosed in Japanese Patent Application Laid-open No. 56-72207. It wasn't.

The feedwater heater recovers the heat of the steam extracted from the turbine into the boiler feedwater. The conventional structure of a U-tube water heater is shown in Figure 2. The U-tube type water heater has a water supply population of 2.
and a water chamber 1 having a water supply outlet 3, a plurality of heating tubes 1 having open ends communicating with the water chamber 1, having a U-shape, and having different bending radii.
2, tube plate 4 for fixing the heating tube 12, feed water heater body 5,
A steam port 8 for introducing steam extracted from the turbine into the body 5, a drain inlet 9 for introducing drain from the outside, and a 5 inside the body 5.
A drain outlet 10 for discharging more condensate, a plurality of heating pipes 1
Furthermore, the heating tube group of the feed water heater includes a condensing section 7 which absorbs the latent heat of steam in the upper part of the feed water heater body 5 and completely heats the feed water in the heating tubes 12; A drain cooler section 6 is formed in the lower part of the body 5 to further cool the drain that has lost latent heat and condensed and liquefied in the condensing section 7 to a temperature below the saturation temperature corresponding to the internal pressure of the feed water heater body side. In addition, 15 is a drain.

The drain/15id liquefied in the condensing part 7 remains in the lower part of the fuselage, and flows from the drain cooler suction port to the drain cooler part 6.
being sucked up to

The accumulated drain 15 is led from the upper and lower seats 11 for level detection to the instrumentation piping 2 (one through) to the instrumentation equipment 18 attached to the equipment, and the drain level is detected and the drain connected to this By opening and closing the valve, the drain level is kept constant. However, the drain level becomes larger as the distance from the suction port 14 increases due to flow path loss, and the drain level increases due to the jet flow from the inlet pipe 8.9 and the inside of the vessel. affected by the fluid dynamic pressure of
The detected value varies greatly depending on the position of the drain level detection seat 11.

If this drain level is higher than necessary, the heat transfer tubes 12 will be soaked with seeds and the heat transfer area will be reduced, and if it is lower than necessary, steam will be drawn in from the suction port 14, so that the drain inside the drain cooler 6 is A phase flow occurs, resulting in poor drainage and damage to components. Therefore, in order to avoid a detection error between the actual drain level and the detected level, the detection point 13 should be placed at a position where the upper seat is not subject to steam dynamic pressure and can detect the average pressure inside the vessel, for example, not near the inlet nozzle head. The lower seat is located at a position where there is little local drift, or at a plurality of representative positions, and is located several hundred mm away from the suction port where it is not affected by suction dynamic pressure and has little variation in drain level.

Therefore, the feed water heater drain level detection point is fixed depending on the internal structure, and the instrumentation seat 11 is installed at this position.

[Problem that the invention seeks to solve]

In the conventional technology, the instrumentation seat 11 that penetrates the fuselage is installed based on the detection point 13, and there is no discussion that the detection point 13t can be set regardless of the installation position of the instrumentation seat 11. However, the installation position of the instrumentation seat 11 did not satisfy the installation requirements of the instrumentation equipment 18 attached to the equipment.

Therefore, if coordination with the instrumentation equipment 18 cannot be achieved, the length of the instrumentation piping 18 or the accompanying increase in the penetrating force of the internal fluid of the instrumentation piping 20 may cause a delay in detection response or release. There were various problems in ensuring the accuracy of the instrumentation, such as detection failures caused by fluid temperature differences due to increased heat.

In particular, in the case of a feed water heater built into the condenser 17, the detection point 13 is located inside the condenser 17, and the instrumentation device 18 is located inside the condenser 17.
7 is set outside the instrument, so instrumentation piping 2 to connect this
0 has two fixed locations: the instrumentation seat 11 that passes through the equipment and the condenser seat 21 that passes through the condenser wall, and requires piping to be routed to relieve thermal stress. Furthermore, condenser 1
The interior of 7 has been strengthened with structural members to improve earthquake resistance, and the piping and
This problem is serious because the increased number of supports has placed stricter restrictions on the route of the instrumentation piping 20, making it extremely difficult to minimize the length of the route.

An object of the present invention is to provide an instrumentation conduit 11 that can satisfy both the positional requirements of the instrumentation detection point 13 and the instrumentation equipment 18, and that can minimize the length of the instrumentation piping 18 system. .

[Means for solving problems]

The above purpose is to connect the detection main tube 16 to the instrumentation conduit 11 installed at a position that satisfies the requirements of the instrumentation device 18 outside the device and extend from the internal structure of the device to the required detection point 13. This is achieved by installing it inside.

[Effect]

The detection main pipe 16 installed inside the fuselage 5 enables direct connection between the detection point 13 and the instrumentation seat 11, which are required to be located at different positions, without interference from surrounding structures of the equipment.

This allows the instrumentation conduit 11 to be positioned in consideration of obstacles on the route of the instrumentation piping 20 caused by structures surrounding the equipment and the installation position of the instrumentation equipment 18, especially in the case of a feed water heater built into the condenser 17. Since it is possible to easily select a position in the middle of the female instrumentation piping 20 that can avoid the heat-stress relaxation measures made of metal, the system of the instrumentation piping 20 can be minimized or omitted.

〔Example〕

An embodiment of the present invention will be explained below with reference to FIG. 1st
In the figure, a feed water heater body 5 is built into the upper body 17 of the condenser, and is located near the drain cooler suction port 14 in the body 5 and at a portion slightly away from the steam port 8 and the drain inlet 9. , a total of three detection points 13 are set. On the other hand, the instrumentation device 18 is arranged outside the condenser 17 on the water chamber 1 side.

By installing a 16-metre detection main tube inside the feedwater heater body 5 that extends from the detection point 13 to the outside of the condenser, instrumentation dust 11 can be recovered without disturbing the fluid in the feedwater heater. It is possible to set the outside of the water container 17, and the instrumentation piping 20t-
Direct communication with instrumentation 18 is possible.

According to this embodiment, due to thermal stress mitigation measures, the instrumentation piping 20 in the 17 condensers, which is required on a long route, can be omitted, and the instrumentation piping 20 can be removed according to the arrangement of the instrumentation equipment 18. 11
Since the position of the sensor can be set, it is possible to minimize the length of the instrumentation system from the detection point 13 to the instrumentation device 18, and the detection accuracy and responsiveness of the drain level and internal pressure are improved.

Furthermore, since structures such as supports attached to the instrumentation piping 20 in the condenser 17 can be omitted, it is also effective in improving plant performance by reducing turbine exhaust loss.

Furthermore, by applying the present invention to a feed water heater other than the one installed inside the condenser 17, it is possible to determine the optimal position of the instrumentation dust 11 according to the installation position of the instrumentation equipment 18.
As in the above example, there are also effects such as the shortest length of the instrumentation system and the reduction of the installation space.

In addition, since the length of the instrumentation piping route can be shortened, it is also possible to reduce the diameter of the piping, and the support related to the instrumentation piping can be greatly reduced, which has the effect of reducing the amount of material and installation space. .

In particular, since the instrumentation piping within the first condenser can be omitted, pressure loss can be reduced as the steam flow path within the condenser is expanded, and a high-performance condenser can also be supplied.

〔Effect of the invention〕

According to the present invention, since the instrumentation dust can be set at a position away from the detection point determined by the structure inside the fuselage, it is possible to minimize or omit the instrumentation piping, which improves the detection accuracy of the instrumentation. Response speed is greatly improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional feed water heater. 11... Instrumentation dust.

Claims (1)

[Claims] 1. An instrument main pipe for detecting the pressure and drain level inside the fuselage is installed inside the fuselage, so that the detection position and the position of the instrumentation seat that penetrates the fuselage are different. feed water heater.