JPH07122802B2 - Safety equipment for plant accessories - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety protection device for a plant auxiliary machine, and more particularly to a safety protection device for a plant auxiliary machine that is subjected to on-site inspection and maintenance.

[Conventional technology]

In a plant such as a thermal power plant, inspection and maintenance of plant auxiliary equipment are appropriately performed in order to maintain healthy operation of the plant, but in this case, it is essential to ensure the safety of maintenance personnel. For this reason, conventionally, when repairing plant auxiliary equipment, etc., an operation prohibition display tag is attached to the operation switch of the auxiliary equipment and its peripheral equipment to prevent erroneous operation of the operation switch by operators other than maintenance staff. I am trying.
Further, as described in Japanese Patent Laid-Open No. 59-91507, by operating a maintenance inspection switch provided in a process input / output device at the time of maintenance inspection of the process control system, a control command is sent from the process control device to the process equipment. There are known process control systems that prohibit.

[Problems to be solved by the invention]

Some of the plant accessories are the condenser water chamber of the thermal power plant, the feed water heater, the coal mill, the fan, the motor, and the pump.
Some have a so-called lid, such as a manhole, a hatch, and a cover, and remove the lid to access the inside for maintenance. Moreover, in many of these cases, a plurality of auxiliaries are installed in parallel to obtain a predetermined output, and therefore some auxiliaries may be stopped to perform a partial load operation to repair the stalled auxiliaries. . When repairing such auxiliary machinery, it is necessary to close the equipment on the inlet and outlet sides, stop the rotating machine, block the inflow of fluid, and discharge the internal fluid. If the equipment is opened or the rotating machine is driven, it will cause a great human injury to the maintenance staff inside.

When considering the safety protection with such auxiliary equipment,
With the method of relying on the operation prohibition display tag and the maintenance / inspection switch of the above-mentioned conventional technology, it is impossible to forget to hang the display tag or forget to operate the maintenance / inspection switch. When the switch is operated, there is a problem that the repaired auxiliary equipment and related equipment are operated and the maintenance staff is injured.

The present invention has been made in view of the above problems,
The purpose is to prevent the entire plant from shutting down so that the repair of the plant auxiliary equipment can be performed while continuing the operation of a part of the system of the plant auxiliary equipment. This is to prevent harm from being caused by unexpected operation of plant equipment.

[Means for solving problems]

A feature of a safety protection device for a plant auxiliary machine according to the present invention for achieving the above object is to include a plurality of systems to which a fluid is supplied and a lid installed in each of the plurality of systems,
A plant auxiliary machine configured so that a person can enter the inside by opening the lid, a fluid supply means provided corresponding to each of the systems, and supplying a fluid to the system, and the fluid supply means. In the safety protection device for plant auxiliary equipment having an operation switch for giving an operation signal to
Each of the lids is provided with lid opening detection means for detecting the opening of the lid, and when at least one of the lid opening detection means outputs a lid opening signal, it corresponds to the system in which the lid is installed. The operation of the fluid supply means is stopped and the operation signal of the operation switch is prevented from being applied to the fluid supply means, and the operation of the fluid supply means corresponding to the other system is continued. I tried to let them do it.

[Action]

A cover opening detector that detects that a cover, a hatch, or a manhole that is opened when repairing plant auxiliary equipment is opened outputs a lid opening signal. When an operator or the like operates the operation switch of the plant auxiliary equipment or auxiliary equipment without knowing the circumstances, an operation signal is output, but the operation signal is satisfied and the lid opening signal is not satisfied (close it). The operation command signal to the plant auxiliary equipment or the auxiliary equipment is output only in the above case. In other cases, the operation command signal is not output. As a result, even if the operation switch is operated by mistake during maintenance of the plant auxiliary equipment, the operation command signal to the plant auxiliary equipment or auxiliary equipment is not output, so unexpected operation of plant auxiliary equipment or auxiliary equipment due to erroneous operation can be avoided. , Does not harm the repair personnel. Further, since the operation of the fluid supply means corresponding to the system where the lid is not opened (that is, the system where the repair is not performed) is continued, the repair can be performed without stopping the operation of all the plant auxiliary machines. Therefore, it is possible to repair and inspect plant auxiliary equipment without stopping the operation of the entire plant.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 13 by taking a thermal power plant as an example.

FIG. 1 shows the basic configuration of the safety protection device 1.
This device is provided with a lid opening detector 2 for detecting that the lid such as a cover, a hatch, or a manhole is opened, and an operation permission signal 5 obtained by inverting the opening detection signal 3 from the detector 2 by the NOT circuit 4. A start (open) operation signal 7 from the operation switch 6 is given to the AND circuit 8 and its output signal 9
Thus, the auxiliary machine 10 is activated only when the operation permission signal 5 and the activation (open) operation signal 7 are satisfied at the same time.
It is not necessary to interlock the lid opening detection signal 3 with respect to the stop (close) side signal of the operation switch 6.

2 and 3 show an example of installation of the lid opening detector in the manhole. In this figure, 100 is a part of the wall of the plant accessory 10, and the lid 102 is opened (3rd part).
(Fig.), Repair staff goes in and out through the manhole hole 101. Lid 102
Is rotatably attached to the wall 100, and the lever 103 and the lid 102 of the lid opening detector 2 such as a micro switch fixed to the wall 100.
Detects that the lid 102 is opened. FIG. 2 shows a state in which the manhole cover 102 is closed. In this case, the lever 103 of the cover opening detector 2 is pressed by the manhole cover 102 and the detector 2 does not output. FIG. 3 shows a state in which the manhole cover 102 is opened, and in this case, the lever 103 of the cover opening detector 2 is released. The lid opening detector 2 determines that the plant auxiliary machine 10 is in the maintenance state with the lever 103 in the released state, and outputs it.
In this example, the rotation of the manhole cover and the micro switch are shown to be engaged with each other to detect the opening, but an appropriate detecting means other than these may be adopted. Further, although it is detected here that the lid is opened, it is also effective to open and judge and output when the open locking mechanism attached to the lid is released.

Specific examples of the present invention will be described below. Fig. 4 shows an example in which the water chambers 11 and 12 of the thermal power plant are used as plant auxiliary equipment. By using two water chambers 11 and 12, the vacuum degree of the water doubler at the rated load is specified. The value is maintained, and in this state, the valves 13, 14, 221, 222 are opened and the valves 15, 16 are closed. Then, for example, in order to maintain the A water chamber 11 while keeping the B water chamber 12 in the operating state, the A water chamber inlet valve 13, the A water chamber outlet valve 14,
All valves of the water chamber bypass valve 15 and the water chamber bypass valve 16 are fully closed, and the cooling water flowing through the B water chamber 12 and the A water chamber inlet valve
13 A water chamber 11 is isolated from the cooling water upstream and A water chamber outlet valve 14 downstream. When the A water chamber 11 is repaired, the A water chamber inlet cover 17, A water chamber inlet manhole 18, A water chamber outlet cover 19, A
One of the water chamber exit manholes 20 is opened to allow maintenance staff to enter the maintenance area.

In this figure, 222B is an inlet valve on the water chamber 12 side, 221 is an outlet valve, 2
24 and 226 are water chamber manholes, and 223 and 225 are water chamber covers, and lid open detectors are attached to all manholes and covers.

FIG. 5 shows an application example of the safety protection device in the maintenance of the condenser A water chamber 11 shown in FIG. A water chamber inlet cover 17, A water chamber inlet manhole 18, A water chamber outlet cover 19, A water chamber outlet manhole 20 with lid open detectors 21, 22, 23, 2 respectively
4 is provided, and if any one of the detectors 21, 22, 23, 24 is detected by the OR circuit 25 as a maintenance state, A water chamber maintenance signal
26 holds. In addition to the detector, the maintenance personnel may install a push button 27 during maintenance of the water chamber A, which is operated on site at the start of maintenance.

When the A water chamber maintenance signal 26 is established, the A water chamber operation permission signal 2 obtained by inverting the maintenance signal 26 by the NOT circuit 28
Since 9 is not established, A water chamber inlet valve 13, A water chamber outlet valve 14,
Even if any one of the operation switches 30, 31, 32 and 33 corresponding to the water chamber bypass valve 15 and the water chamber bypass valve 16 is opened, the respective valves 13,
The opening operation instruction signals 34, 35, 36, 37 for 14, 15 and 16 are not established, so that all the valves do not open. Further, in addition to the operation switches 30, 31, 32, 33, a similar opening operation prohibiting circuit may be installed for an automatic opening operation circuit such as a sequencer. Further, the A water chamber maintenance signal 26 may be used to inform the operator that the A water chamber 11 is currently in a maintenance state by a display lamp on the operation switch or a computer display screen.

Similar to the case of the A water chamber 11, the safety protection device for maintenance of the B water chamber 12 is configured as follows. B water chamber inlet cover 225, B water chamber inlet manhole 226, B water chamber outlet cover 223,
B Lid open detectors 227 to 2 at water chamber exit manhole 224
When the OR circuit 232 is provided with 30 and any one of the detectors 227 to 230 detects the maintenance state, the B water chamber maintenance signal 233 is established. In addition to the detectors 227 to 230, a push button for maintenance of water chamber B operated by the maintenance staff at the site at the start of maintenance.
231 will also be installed.

When the B water chamber maintenance signal 233 is established, the B water chamber operation permission signal 235 obtained by inverting the maintenance signal 233 by the NOT circuit 234 is not established, so the B water chamber inlet valve 222 and the B water chamber Opening operation command signal 13 to each of the valves 222, 221, 15 and 16 regardless of whether the operation switches (236, 237), 32 and 33 corresponding to the outlet valve 221, the water chamber bypass valve 15 and the water chamber bypass valve 16 are opened.
Since 8,239,36,37 are not established, all the valves 222,221,15,16 are not opened.

According to the present embodiment, it is possible to prohibit the opening operation of all the valves 13, 14, 15, 16 connected to the A water chamber 11 during maintenance of the A water chamber 11, so that the operator mistakenly operates the operation switch 30, It is possible to prevent the cooling water from flowing into the A water chamber 11 by opening any one of 31, 32, and 33, which has the effect of preventing personal accidents in which the maintenance staff may be drowned in the water or drowned. Similarly, all valves 222, 221, 15, 1 connected to B water chamber 12 are maintained during maintenance of B water chamber.
Since the opening operation of 6 can be prohibited, it is possible to prevent the cooling water from flowing into the B water chamber 12 even if the operator mistakenly opens any of the operation switches 236, 237, 32, 33. A characteristic of this embodiment is that the valves 15 and 16 for bypassing between the water chambers are locked during any maintenance.

FIG. 6 shows a system of feed water heaters 111 and 112, which are plant auxiliary equipment, and the water supply from the condenser is performed through three routes of two feed water heaters 111 and 112 of the parallel device and a bypass valve 240 that is open during operation. Can be supplied to the boiler. This feed water heater is supplied with bleed air from the turbine through bleed stop valves 115 and 242 to heat the feed water. Note that 113 and 243 are water supply inlet valves, and 114 and 241 are water supply outlet valves. In this case, 111,114a,
The system A consisting of 115a, 113a and the system B consisting of 112, 114a, 115a, 113a are independent of each other, and there is no device that must be locked for maintenance of any system as in the case of FIG. In the following, only system A will be described, and description of system B will be omitted.

In this water supply system, in order to maintain the A water supply heater 111 while keeping the B water heater 112 in an operating state, the A water heater water supply inlet valve 113a, A water heater heater water supply outlet valve 114a, A water heater The extraction stop valve 115a is fully closed and the other valves are opened to isolate the A supply water heater 111 from the supply water and the extraction air flowing into and out of the B supply water heater 112. Also, A water heater 111
When repairing, the A water heater heater manhole 116a is opened and the maintenance staff enters the maintenance area.

FIG. 7 shows an application example of the safety protection device in maintenance of the feed water heater shown in FIG. 6, and only system A maintenance will be described. A feedwater heater manhole 116a is provided with (lid open) detector 117a, and the OR circuit 119a allows the detector 11
When the maintenance state is detected by 7a, when the maintenance personnel operates the push button 118a during maintenance of the A water heater, the A water heater maintenance signal 120a is established. The push button 118a does not have to be installed. When the A feedwater heating maintenance signal 120a is established, the A feedwater heater operation permission signal 122a obtained by inverting the maintenance signal 120a by the NOT circuit 121a is not established, so that the A feedwater heater feedwater inlet valve 113a, Even if any of the operation switches 123a, 124a, 125a corresponding to the A feed water heater feed water outlet valve 114a and the A feed water heater bleed stop valve 115a is opened,
Opening operation command signals 126a, 127a, 128a for 113a, 114a, 115a
Does not hold, and all the valves do not open. It is not necessary to interlock the lid opening detection signal with respect to the operation signal for closing the operation switches 123a, 124a, 125a.

According to this embodiment, since the opening operation of all the valves 113a, 114a, 115a connected to the A feed water heater 111 can be prohibited during maintenance of the A feed water heater 111, the operator mistakenly operates the operation switch.
Personal injury that can prevent water supply or bleed air from flowing into the A water heater 111 by opening any of 123a, 124a, 125a, and cause maintenance personnel to be burned or drowned by high temperature and high pressure water supply or bleed air. Has the effect of preventing

FIG. 8 shows an example of a pulverized coal machine as a plant auxiliary machine. Here, the pulverized coal machine 38 supplies pulverized coal as a fuel to the boiler 241, and a plurality of pulverized coal machines 38 are provided in one boiler 241, and coal supplied from the coal feeder 41 is supplied to the boiler 241. After pulverizing with a rotating body to make pulverized coal, carry air 242
To supply pulverized coal to the boiler. In the example of the figure, 2 of a and b
The example of the pulverized coal machine having a series is shown, and the pulverized coal machine
In 38, in order to maintain the inside of the a-series pulverized coal machine 38a while keeping the b-series pulverized coal machine 38b in an operating state, a coal gate 40a for blocking coal flowing from the coal bunker 39a into the coal feeder 41a is installed. Close, stop the coal feeder motor 42a that inputs coal from the coal feeder 41a to the pulverized coal machine 38a, and stop the pulverized coal motor 43a that turns the coal that is input from the coal feeder 41a into pulverized coal,
The primary air damper 44a that blocks the hot air, which is the carrier air, from flowing into the coal feeder 41a is closed to prevent the flame in the furnace and the pulverized coal from other pulverized coal machines from flowing back. The pulverized coal single machine outlet damper 45a is closed, and the coal, primary air, flame, and pulverized coal flowing from the pulverized coal 38a into the pulverized coal machine 38
Isolate a and stop the rotating body 46a in the pulverized coal machine 38a.
Further, when maintaining the inside of the pulverized coal machine 38a, any one of the plurality of pulverized coal machine hatches 47a is opened to allow the maintenance staff to enter the maintenance area.

FIG. 9 shows a safety protection device for maintenance in the pulverized coal machine 38 shown in FIG. 8. Since the same logic may be used for both the a system and the b system, only an example of the a system will be described below. A plurality of pulverized coal machine hatches 47a are each provided with a lid opening detector 48a, and a plurality of the detectors 48a are detected by the OR circuit 49a.
When the maintenance worker operates the push button 50a during maintenance of the pulverized coal machine, the pulverized coal maintenance signal 51a is established. The push button 50a does not have to be installed.

When the pulverized coal machine maintenance signal 51a is established, the pulverized coal machine operation permission signal 53 obtained by inverting the maintenance signal 51a by the NOT circuit 52a is not established, so the coal gate 40a, the primary air damper 44a, the fine powder Even if any one of the operation switches 54a, 57a, 58a corresponding to the charcoal machine outlet damper 45a is opened, the closing operation command signals 59a, 62a, 63a for the respective devices are not established, and all the respective devices do not open. .

Further, the start command signals 60a, 61a for the respective motors are not established even if the operation switches 55a, 56a corresponding to the coal feeder motor 42a and the pulverized coal motor 43a are operated, and the motors Does not start.

According to the present embodiment, during maintenance of the pulverized coal machine, it is possible to prohibit the opening operation and the startup of all the auxiliary machines 40a, 42a, 43a, 44a, 45a related to the pulverized coal machine 38a, so that the operator can Incorrect operation If any of the switches 54a and 55a is operated, the coal will be pulverized coal 38a.
It flows into the inside and the maintenance staff is buried in the coal, and the operation switch 57
Even if either a or 28a is operated, hot air, flame, or pulverized coal flows into the pulverized coal machine 38a to cause burns to the maintenance staff, or the rotating body 46a rotates even if the operation switch 56a is operated. This has the effect of preventing personal injury that would result in the maintenance worker being bitten and the repair worker dying at worst.

FIG. 10 is a system diagram showing a forced draft fan for supplying air to a boiler and its associated auxiliary equipment as an example of plant auxiliary equipment. In order to maintain the inside of the A-series forced draft fan 131a while keeping the B-series forced draft fan operating, in the forced draft fan composed of a plurality of such forced draft fans,
132a is stopped, and the forced draft fan outlet danapa 133a that blocks the reverse flow of air from the forced draft fan is closed. At this time, the forced draft fan blades 134a are at the minimum opening. Further, when maintaining the inside of the forced draft fan 131a, the forced draft fan manhole 135a is opened so that a maintenance staff enters the maintenance area.

FIG. 11 shows an application example of the safety protection device for maintenance in the forced draft fan 131a shown in FIG. The opening fan detector 136a is installed in the pushing fan manhole 135a, and the OR circuit 138a
Thus, when the detector 136a detects the open state or when the maintenance person operates the push button 137a during maintenance of the forced draft fan, the forced draft fan maintenance signal 139a is established. The button 137a does not have to be installed.

When the push-in fan maintenance signal 139a is established, the push-in fan operation permission signal 141a obtained by inverting the maintenance signal 139a by the NOT circuit 140a is not established, so that the operation switch corresponding to the push-in fan motor 132a is activated. Even if the 142a is started, the start command signal 145a for the motor 132a is not established,
The motor 132a will not start. In addition, the opening operation command signals 146a and 147a for the respective auxiliary devices are not established even if any one of the operation switches 143a and 144a corresponding to the forced draft fan outlet damper 133a and the forced draft fan moving blades 134a is opened, and the respective auxiliary switches are not established. All machines do not open.

According to the present embodiment, the forced draft fan 13 is pressed during maintenance of the forced draft fan.
Since it is possible to prohibit the starting and opening operations of all the auxiliary devices 132a, 133a, 134a related to 1a, even if the operator mistakenly operates any of the operation switches 142a, 144a, the movable part of the forced draft fan 131a. When the operation switch 143a is operated, air flows backward to the forced draft fan 131a, and the forced draft fan motor 142a and the moving blades 144a reverse, causing the maintenance staff to fall or be caught in a movable part. And, in the worst case, it has the effect of preventing accidents that could result in death of maintenance staff.

FIG. 12 shows a conceptual diagram of a motor and a pump as a plant auxiliary machine. The rotating parts of the motor 64 and the pump 65 are protected by a casing, etc.
The shaft connecting the 65 and the rotary shaft 66 at the end or the rotary shaft 66
The bearing portion 67 for supporting the motor is covered by a plurality of rotating portion covers 68. In order to remove the cover 68 when repairing the motor 64, pump 65, rotating shaft 66 or bearing 67,
The rotating shaft 66 and the bearing 67 are exposed.

FIG. 13 shows an application example of the safety protection device for maintenance of the motor 64, the pump 65, the rotating shaft 66 or the bearing portion 67 shown in FIG.

A lid opening detector 69 is attached to each of the plurality of rotating unit covers 68.
When the maintenance state is detected by any one of the multiple detectors 69 by the OR circuit 70, or when the maintenance person operates the push button 71 during pump and motor maintenance on site, the pump and motor maintenance state Signal 72 holds. The push button 71 may not be installed.

When the pump / motor maintenance status signal 72 is established, the motor start permission signal 74 obtained by inverting the maintenance status signal 72 by the NOT circuit 73 is not established, so the operation switch 75 corresponding to the motor 64 is started. Even if operated, the start command signal 76 for the motor 64 is not established, and the motor 64, the pump 65, the rotary shaft 66, and the bearing 67 are all stationary and remain stationary.

According to the present embodiment, it is possible to prohibit the rotation operation of all parts of the motor 64, the pump 65, the rotary shaft 66, or the bearing part 66 during maintenance, so that the operator mistakenly operates the operation switch 75. Even if the maintenance staff gets caught up in the rotating part, it has the effect of preventing personal injury.

〔The invention's effect〕

According to the present invention, it is possible to automatically detect that plant equipment and auxiliary equipment are under maintenance and prevent dangerous operations of related equipment due to erroneous operation.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of the present invention, FIGS. 2 and 3 are examples of installation of a maintenance state detector in a manhole, FIG. 4 is a system diagram around a condenser, and FIG. 5 is a condenser water chamber. Application example of protective device, Fig. 6 is a system diagram around feed water heater, Fig. 7 is an application example of feed water heater protection device, Fig. 8 is a system diagram around pulverized coal machine, and Fig. 9 is an application example of pulverized coal machine protection device. , Fig. 10 is a system diagram around the forced draft fan,
Fig. 11 is an example of application of a forced draft fan protection device, Fig. 12 is a conceptual diagram of a pump and motor, and Fig. 13 is an example of application of a pump and motor protection device. 1 ... Safety protection device, 2 ... Lid opening detector, 3 ... Maintenance status signal, 5 ... Operation permission signal, 9 ... Start (open) operation command signal, 11 ... Condenser A water chamber, 17,19 …… Water chamber cover, 18,20 …… Water chamber manhole, 29 …… A Water chamber operation permission signal, 38 …… Pulverized coal machine, 47 …… Pulverized coal machine hatch, 53 ……
Pulverized coal machine operation permission signal, 64 …… motor, 68 …… rotating part cover, 74 …… motor start permission signal.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-53-16175 (JP, A) JP-A-59-91507 (JP, A) Actually open 55-124696 (JP, U) Actual-open Sho-56- 29699 (JP, U) Actual opening Sho 58-7631 (JP, U) Actual opening Sho 60-48003 (JP, U)

Claims (1)

[Claims] 1. A plant auxiliary system comprising: a plurality of systems to which a fluid is supplied; and a lid installed in each of the plurality of systems, wherein the lid is opened so that a person can enter therein. A machine, a safety protection device for a plant auxiliary machine, which is provided corresponding to each of the systems and has a fluid supply means for supplying a fluid to the system, and an operation switch for giving an operation signal to the fluid supply means, Each of the lids is provided with lid opening detecting means for detecting the opening of the lid, and when at least one of the lid opening detecting means outputs a lid opening signal, it corresponds to the system in which the lid is installed. While stopping the operation of the fluid supply means,
A plant auxiliary machine, characterized in that the operation signal of the operation switch is prevented from being applied to the fluid supply means, and the operation of the fluid supply means corresponding to the other system is continued. Safety protection device.