JP4703365B2 - Blow operation method of power generation system - Google Patents

Description

  The present invention relates to a blow operation method for a power generation system in which a blow operation is performed for inspection of work locations in a power generation system that is systematized by connecting a large number of work sites.

  Conventionally, in this type of power generation system, each work site and the entire inspection are regularly performed. In this case, the inspection operation is performed for each work site, but valves are arranged before and after the inflow path of water / steam so that there is no inflow of water / steam, etc. to the work site to be inspected. A blow operation is performed to close the front and rear valves and stop the operation of the target work site. This blow operation is performed individually for each work site, and at least two valves are opened and closed in one work site, that is, the work site.

  In conventional power generation system inspection work, performing a blow operation that closes the front and rear valves for each of a large number of work sites increases the amount of operation of the front and rear valves, increasing the work load, and performing regular inspections within a certain period of time. Trying to do so requires a lot of workers. In addition, the power generation system is a combination of extremely complicated routes, and it is difficult to identify the range of work site identification and to identify which front and rear valves should be operated. Specifically, the individual work parts of the power generation system are inspected individually, but in accordance with the work slip, the power is supplied so that the movable parts such as motors do not rotate after the operation prohibition tag is attached to each work part. Turn off the power and close the front and rear valves so that water, steam, etc. do not flow, and when the inspection is completed, turn on the power and open the front and rear valves. In some cases, close the valves to prevent backflow. This operation must be repeated for a large number of work sites. For example, in a certain power plant, an inspection work in a power generation system equipped with one generator is in a state where it takes 12 days by 12 to 13 workers.

The blow operation method of the power generation system of the present invention includes the edge cutting means disposed at the disassembly points upstream and downstream of the four system blocks of the condensate system, the water supply system, the boiler system, and the seawater system provided in the power generation system. a step of blowing the power and water supply of each system block in each of the system blocks, the inspection operation without the opening and closing of the front and rear valves for each working position one of the strains block while blow by the edge cutting means comprising a row cormorants step, a step of releasing the blown state by the edge cutting means after completion of the inspection of all the worksite, the.

Since the present invention is blown by the edge cutting means for every four system blocks of the condensate system, the water supply system, the boiler system, and the seawater system , in the system block that has been blown, the opening and closing operation of the front and rear valves of each work site It is possible to perform the inspection work by the worker freely without any trouble, and to reduce the operation amount while ensuring the safety of the worker, and to perform the quick inspection work. It has an effect.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an example of a power generation system equipped with Units 1 and 2, where Unit 1 is coal and fuel, and Unit 2 is high-temperature and high-pressure steam generated in a boiler using heavy oil and crude oil as fuel ( The turbine is rotated at high speed using the thermal energy (kinetic energy), and further, the power generator (electric energy) is generated by a generator having the same rotating shaft as the turbine. Also, in the process of generating electricity, in order to minimize the impact on the environment as much as possible, a denitration device, an electric dust collector, and a desulfurization device are installed as measures to prevent air pollution, and a wastewater treatment device and desulfurization device are installed as measures to prevent water pollution. Nitrogen equipment, etc. is installed, and rotating equipment is installed indoors and silencers are installed on safety valves as measures against noise and vibration.

  In the power generation system configured in this way, the blow range necessary for inspection work is separated into four large systems: boiler system, water supply system, condensate system, and seawater system, and the work system is completely blown. Thus, while ensuring the safety of the operator, the opening / closing operation of the front and rear valves for each work location is unnecessary, and inspection work with a small amount of operation is enabled.

  That is, first, in order to manage work in each system, in principle, the systems are separated by a system separation valve that functions as an edge cutting means so that there is no inflow of water, steam, etc. from multiple systems. In this case, an operation prohibition tag specifying the system is attached to the corresponding system isolation valve, and the system isolation valve is not opened until all operations are completed. Also, if system separation is not possible due to inspection of the system isolation valve itself, etc., the substitute valve is closed and the operation prohibition tag is replaced. Furthermore, when the system separation valve separates two systems at the same time, the operation prohibition tag of both systems is attached, and when the operation of one system is completed, the operation prohibition tag of the system being worked on is completed. And collect only the operation prohibition tags of the completed system.

  Prior to such blow work, a list of system diagrams in which inspection parts of the system block in a state blown by the edge cutting means are determined in advance is given to the worker. In addition, for example, various types of valves used in the boiler system are very numerous as shown in Tables 1 to 3, and these Tables 1 to 3 include valve names and valve numbers. Is indicated, and the open / close state of each valve during normal operation, the open / close state during system blow, and the open / close state during water filling are displayed. Here, the system separation valve functioning as the edge cutting means is a valve described as “disassembly point”. Specifically, the heater right spray stop valve 3V-33A (water supply system blow decomposition point), the heater left side Spray stop valve 3V-33B (water supply system blow disassembly point), # 7 water heater heating water supply outlet valve 3V-118 (water supply system blow disassembly point), # 7 water heater heating water supply bypass valve 3V-119 (water supply system blow disassembly point) ), Reheater spray stop valve 2V-19 (water supply system blow disassembly point), A-BCP seal water inlet valve 4V-102A (E lock, water supply system disassembly point), A-BCP seal water outlet valve 4V-113A (E-lock, condensate system disassembly point), B-BCP sealed water inlet valve 4V-102B (E-lock, feed water system disassembly point), B-BCP sealed water outlet valve 4V-113B (E-lock, condensate system disassembly) Point), C-BCP sealed water Source valve 4V-102C (E lock, Water System decomposition point), C-BCP seal water outlet valve 4V-113C (E lock, condensate system decomposition point), and the like.

  Moreover, although only a part is shown as a specific piping diagram, for example, blow system diagrams of a boiler system are shown in FIGS. This state of illustration shows only a part of the boiler system, and although illustration is omitted, a similar blow system diagram exists for the water supply system, the condensate system, and the seawater system. .

Next, the system blow valve / air vent valve is opened. That is, after the system is separated by the system separation valve as the edge cutting means, each air vent valve / blow valve is opened to completely blow the working system. As a general rule, attach an operation prohibition tag specifying the system to the opened valve and keep it open until the work in the system is completed. However, it shall be closed in the following cases.
(1) In the blow valve, there is a backflow from the drain pipe after system blow, which hinders work or equipment storage.
(2) The piping blow in the system has been completed, and opening and closing operations are necessary for work convenience. In this case, an auxiliary slip for the corresponding work is attached to the valve.
(3) The device in the system is completely blown, and there is a risk of dropping or falling when the valve is opened by work in the device (for example, a condenser outlet valve).

Furthermore, as for the manual valve that has performed the system blow operation of the system block in the blown state, an operation prohibition tag is attached in principle until the system is restored. The valve to which the operation prohibition tag is attached is as follows.
(A) Even if the valve is always open, an operation prohibition tag is attached to the system separation valve.
(B) For pipes that are attached in series to the pipe and are always "open", only "open" confirmation at the time of pipe blow is allowed, and an operation prohibition tag is attached only to the opened valve. It shall be attached.
(C) If it is not possible to blow completely in the system by a check valve, etc., and there is a possibility of inflow to the system side when the valve is "open", close the valve and remove the operation prohibition tag Install.

  Next, a description will be given of the power lock of the motor-operated valve / auxiliary machine related to the system blow operation. The power lock is applied to the system isolation valve, and it cannot be blown completely in the system by a check valve or the like, and there is a possibility of inflow to the system side when the valve is opened. This is done in some cases. Operation prohibition tags that clearly indicate the system are attached to these power lock points. Furthermore, when the power supply lock of auxiliary equipment such as a pump is operated by system blow, the power supply lock is performed before the system blow operation is performed for those that are idle or closed.

  The electric valve / air operated valve tagging operation (CRT tagging operation) related to the system blow operation does not correspond to the system separation valve, and the system is completely blown by system blow. Even if the valve opens and closes, the safety of the work is not hindered.

Next, how to handle the work slip and how to proceed with the work will be described. Since the work slips are filled in with the contents of the isolation blow operation for each work range as before, it is necessary to consider whether each work slip can be handled by the system blow operation. Also, as a general rule, at the recovery stage of the system blow, if all the work in the system is not completed, the system blow cannot be recovered, so it is necessary to grasp all the work in the system.
1. System blow range setting / preparation Perform the following preparations before starting the periodic inspection work in advance so that the work table can be transferred smoothly after the system blow starts.

a. System blow range setting Set the system isolation valve and blow valve by referring to the valve inspection list and work contents submitted by the person in charge of construction.

b. Creating a valve checklist / system diagram After determining the system isolation valve and blow valve, create a valve checklist / system diagram with the system isolation / blow operation location.

c. Examination of operation content Consider the operation that can be handled by system blow operation with reference to the work sheet list.
2. Implementation of system blow operation When periodic inspection is started and the water pressure test of the water heater is completed, and the blow operation of that system becomes possible, the system blow operation is performed using the valve checklist and system diagram prepared in advance. Do.
3. About examination of operation contents of work slip a. Regarding the issuance criteria of auxiliary slips (work operation signs) (1) For valve operations and power locks that can be handled by system blow according to the contents of the work slip, no supplementary slip will be issued, and system blow is entered in the work slip To do. However, for inspection of pumps and motor-operated valves and work safety, auxiliary slips (work operation signs) are required even if the power supply lock is required or work operation signs are required even if the power is locked by system blow. ) And attach to the power lock location.

(2) For valve operations and power supply locks at locations that cannot be handled by system blow in the contents of the work slip, issue an auxiliary slip and perform individual operations.
4). Handling at work delivery a. Precautions when handing work slips (1) When handing work slips to the person in charge of construction, if the work slips can be handled within the scope of the system blow investigation and differ from the contents described in the work slips, the operation details should be sent to the person in charge of construction. Explain and get consent.

  (2) When handing over the work slip to the person in charge of construction, after performing the system blow operation, confirm that the blow has been completed completely.

b. Understanding work locations within the system blow range When accepting work slips, all work slips within the system blow are entered in the system blow operation-related work list, and work locations and contents within each system blow range are understood. deep.
5. Handling during and after work a. Understanding the remaining work within the system blow range (1) When returning the work slip, fill in the completion date in the work list related to the system blow operation for all work within the system blow and check the remaining work within each system blow range. Keep track.

b. Handling at the time of test operation (1) When the part where the power supply of the auxiliary machine is locked by the system blow performs the motor unit test operation, the power supply can be restored only during the test operation, and the system blow operation prohibition tag can be removed. To do. However, after the trial run is complete, lock the power supply and attach an operation prohibition tag.

  (2) If the location where the auxiliary power supply is locked due to system blow performs a test run on the actual machine, the power supply will be restored if the system restoration (until water filling of the trial run equipment) has not been completed. Shall not be allowed.

c. Precautions before system restoration (1) In order to perform system restoration, all work in the system must be completed, so the planned date of restoration of the system must be notified in advance to the construction staff. Have work tickets returned by day. If it is unavoidable that the work cannot be completed, if there is no problem in restoring the system, the operation is switched to an individual operation, and a supplementary slip issuance / valve operation is performed so that the system can be restored.

d. Precautions for system restoration (1) In order to perform system restoration, all work in the system must be completed, so work completion is confirmed by the system blow operation related work list and on-site confirmation. If there is no problem, the system will be restored.

  In this way, the system is divided into various system blocks such as a condensate system, a water supply system, a boiler system, and a seawater system, and an edge cutting means that blows the power and water supply of each system block for each system block is provided upstream of each system block. After the inspection of all work points, the inspection operation is performed without opening and closing the front and rear valves for each work point with either system block blown by the edge cutting means. According to this embodiment in which the blown state by the edge cutting means is released, the inspection work that previously took 5 days by 12 to 13 workers can be completed in 2 days by 7 to 8 workers. It was possible. This point is due to the fact that the number of valves to be opened / closed dramatically has been reduced compared to the conventional method of performing inspection work by opening / closing the front / rear valves at the individual work locations. Moreover, since the operation blow can be performed for each rough system, the safety for workers is extremely high in the system block where the operation is blown, and the occurrence of accidents during the work is eliminated.

The embodiment of the present invention is shown, and is a schematic system diagram showing an example of a power generation system. It is a boiler system blow system diagram. FIG. 3 is a boiler system blow system diagram subsequent to FIG. 2. FIG. 4 is a boiler system blow system diagram subsequent to FIG. 3. FIG. 5 is a boiler system blow system diagram subsequent to FIG. 4. FIG. 6 is a boiler system blow system diagram subsequent to FIG. 5. FIG. 7 is a boiler system blow system diagram subsequent to FIG. 6.

Claims (5)

Condensate lines generating system comprises a water supply system, boiler system, four by edge cutting means disposed on the decomposition point in each of the upstream and downstream of the system blocks, the power and water supply, etc. of the respective systems block systems of seawater system A process of blowing block by block ;
And line Cormorant step inspection operation without the opening and closing of the front and rear valves for each working position blow state by either of the above systematic block edge cutting means,
Releasing the blown state by the edge cutting means after completing the inspection of all work points ;
Blow Operation of the power generation system, characterized in that it comprises a.   2. The blowing operation method for a power generation system according to claim 1, wherein an operation prohibition tag is attached to the operated edge cutting means.   The blow operation of the power generation system according to claim 1 or 2, wherein a list of system diagrams in which inspection parts of the system block in a state blown by the edge cutting means are blown before the start of the inspection operation is passed to the worker. Method.   The power generation system according to claim 1, 2 or 3, wherein when the system separation cannot be performed by inspection of the edge cutting means itself, an alternative valve of the edge cutting means is closed and an operation prohibition tag is attached. Blow operation method.   When two system blocks are blown by one edge cutting means, attach an operation prohibition tag for both systems, and when the operation of one system block is completed, leave an operation prohibition tag for the system block being worked on. 5. The blow operation method for a power generation system according to claim 1, wherein only the operation prohibition tags of the completed system block are collected.

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