CN108811195B

CN108811195B - Drying and finished product protecting device and method for voltage stabilizer heater of nuclear power station

Info

Publication number: CN108811195B
Application number: CN201810640206.9A
Authority: CN
Inventors: 付贵龙
Original assignee: Shanghai Nuclear Engineering Research and Design Institute Co Ltd
Current assignee: Shanghai Nuclear Engineering Research and Design Institute Co Ltd
Priority date: 2018-06-20
Filing date: 2018-06-20
Publication date: 2021-05-18
Anticipated expiration: 2038-06-20
Also published as: CN108811195A

Abstract

The invention discloses a drying and finished product protecting device and method for a voltage stabilizer heater of a nuclear power station. The device comprises a drying shed consisting of an inner screen and a peripheral screen, wherein a heater is arranged at the top of the inner screen, the outer side of the inner screen is provided with the peripheral screen, the peripheral screen extends upwards to a voltage stabilizer, and the top of the inner screen is communicated with the peripheral screen; the outer screen is provided with an air outlet, and the air heater outside the outer screen is communicated with the inside of the inner screen through an air pipe. And opening the air heater, blowing hot air blown out by the air heater into the inner peripheral screen, blowing the hot air to the heater in a directional manner, and then blowing out the outer peripheral screen through the air outlet of the outer peripheral screen. The invention adopts the heating and convection mode to dry the heater at the same time, so that the external air can not enter the drying shed all the time, and the heater is protected from being affected with damp; the invention carries out full-coverage drying protection on all heaters, has high drying efficiency and large protection range of finished products, and can be extended to the insulation drying and finished product protection of all the nuclear power station voltage stabilizer heaters.

Description

Drying and finished product protecting device and method for voltage stabilizer heater of nuclear power station

Technical Field

The invention relates to a drying and finished product protecting device and method for a voltage stabilizer heater of a nuclear power station.

Background

The voltage stabilizer is one of main equipment in a nuclear power station, in a latest AP1000 nuclear power station in the world, the diameter of the voltage stabilizer is about 3M, 78 heaters are arranged at the bottom of the voltage stabilizer, the first reactor three-door nuclear power station is tested before the cable termination, 2 heaters are found to have insulation resistance values which do not meet the requirement that the design specification is not less than 200M omega, and meanwhile, the #2 island voltage stabilizer heaters are detected, and 35 heaters are found to be unqualified. The reason is that moisture in the factory building enters the insulated interior of the heater and needs to be dried to drive away the moisture.

The existing solution is to use a vacuum pump to connect the end of the heater for vacuum drying, but the effect is very little, although the insulation value is improved, the distance from the qualified standard is still very far, and the method can only process 1 piece at a time, and the efficiency is quite low.

Disclosure of Invention

The invention aims to solve the problems that: the invention relates to a method for protecting a voltage stabilizer heater of a three-door nuclear power station, which is used for ensuring that the #1 island and the #2 island of the three-door nuclear power station are all treated to be qualified after being wetted, and the voltage stabilizer heater is protected by the method of the invention until the protection is released before the cable is terminated.

In order to solve the problems, the invention is realized by the following technical scheme:

a drying and finished product protecting device for a heater of a voltage stabilizer of a nuclear power station is characterized by comprising a drying shed consisting of an inner surrounding screen and a peripheral screen, wherein the heater is arranged at the top of the inner surrounding screen; the outer screen is provided with an air outlet, and the air heater outside the outer screen is communicated with the inside of the inner screen through an air pipe.

Preferably, the air pipe is arranged at the bottom of the drying shed.

The invention also provides a drying and finished product protecting method for the heater of the voltage stabilizer of the nuclear power station, which is characterized in that the drying and finished product protecting device for the heater of the voltage stabilizer of the nuclear power station is adopted, the hot air blower is turned on, hot air blown out by the hot air blower is blown into the inner peripheral screen, the hot air is blown to the heater in a directional mode, and then the hot air is blown out of the outer peripheral screen through the air outlet of the outer peripheral screen. Along with the blowing in of continuous hot-blast, the pressure-fired pressure has been formed in the whole drying shed, air in the drying shed can make the air outlet of peripheral screen slightly open and flow to outside the canopy, under such continuous convection, original moist air can be blown in the dry air of canopy and completely replaced in the final canopy, and simultaneously, the electric heater of interior peripheral screen top also can receive dry air's infiltration, then, the moisture in the electric heater also can be replaced gradually and has been promoted electrical insulation resistance, finally reach qualified standard. And continuously introducing hot air into the drying shed until the cable is terminated, so as to ensure that moist air does not enter the drying shed to damp the electrical equipment again, thereby protecting the finished product of the electric heater.

Preferably, the air heater is provided with an over-temperature protection device, when the temperature in the drying shed reaches a set value of the air heater, the air heater automatically starts the over-temperature protection device immediately and cuts off a power supply, the air heater is protected from being burnt or the phenomenon of over-temperature in the drying shed is avoided, and the maintenance amount of manual intervention is reduced.

Compared with the prior art, the invention has the beneficial effects that:

1. the invention adopts the heating and convection mode to dry the heater at the same time, so that the external air can not enter the drying shed all the time, and the heater is protected from being affected with damp;

2. the invention carries out full-coverage drying protection on all heaters, the whole heater is arranged in the drying shed, the drying efficiency is high, and the protection range of finished products is large;

3. the invention can be extended to the insulation drying and finished product protection of all nuclear power station voltage stabilizer heaters;

4. the invention sets overtemperature protection, reduces human intervention, ensures safety, saves manpower, has quite small maintenance amount at ordinary times, and can be on duty without people for a long time.

Drawings

FIG. 1 is a schematic diagram of a nuclear power plant pressurizer heater drying and product protection device provided by the invention.

Detailed Description

In order to make the invention more comprehensible, preferred embodiments are described in detail below with reference to the accompanying drawings.

Examples

As shown in fig. 1, a schematic diagram of a drying and finished product protecting device for a nuclear power station voltage stabilizer heater provided by the invention comprises a drying shed consisting of an inner screen 1 and a peripheral screen 2, wherein a heater 6 is inserted into the inner screen 1 from the top, the peripheral screen 2 is arranged on the outer side of the inner screen 1, the peripheral screen 2 extends upwards to a voltage stabilizer 5, and the top of the inner screen 1 is communicated with the peripheral screen 2; the outer screen 2 is provided with an air outlet 2-1, an air heater 3 outside the outer screen 2 is communicated with the inside of the inner screen 1 through an air pipe 4, and the air pipe 4 is arranged at the bottom of the drying shed.

The installation method of the device comprises the following steps:

step 1 setting up drying shed

Step 1.1, setting up an inner screen 2: the inner surrounding screen 1 is surrounded into a cylinder, the upper end of the cylinder is open, and the projection of the upper end surface on the voltage stabilizer 5 comprises all voltage stabilizer heaters 6; the upper portion of the inner enclosure screen 1 is suspended on a support of the voltage stabilizer 5 through 8-10 ropes, and the lower portion of the inner enclosure screen and the ground form a lower sealing surface.

Step 1.2, setting up a peripheral screen 2: the peripheral screen 2 encloses into a drum, and the up end forms the sealed face with equipment in close contact with, ties firmly on stabiliser 6 with the rope, and the lower part forms the sealed face of lower part with ground, evenly sets up 6 ~ 10 air outlets of automatic start-stop along the circumference in the bottom.

Step 2, an air heater 3 is arranged: the fan mouth of air heater 3 is equipped with air purification device, the thermal protection definite value of adjustment air heater 3, the temperature definite value is selected according to the temperature outside the drying shed, if the outside temperature of drying shed 15 ℃, select low value 25 ℃ (low value generally selects 5 ~ 10 ℃ higher than outside the drying shed), high value selects 30 ℃ (high value is 10 ~ 15 ℃ higher than low value), namely the temperature stops heater and the fan in air heater 3 and stops blowing hot-blast when high value 30 ℃ in the drying shed, 25 ℃ restarts heater and fan and blows hot-blast when low value.

And 3, inserting the air pipe 4 into the inner enclosure screen 1.

And step 4, switching on a power supply of the air heater 3, putting into thermal protection, and blowing hot air into the inner surrounding screen 1 of the drying shed. Along with the blowing-in of continuous hot-blast, the pressure-fired pressure has been formed in the whole drying shed, the air in the drying shed can make the air outlet 2-1 of peripheral screen 2 open slightly and flow to the shed outside, under such continuous convection, the original moist air in the final shed can be replaced completely by the dry air of blowing in the shed, simultaneously, heater 6 of interior peripheral screen 1 top also can receive the infiltration of dry air, then, the moisture in the heater 6 is also can be replaced gradually and has been out thus promoted electrical insulation resistance, finally reach qualified standard. And continuously introducing hot air into the drying shed until the cable is terminated, so as to ensure that moist air does not enter the drying shed to damp the heater 6 again. If in case the temperature in the drying shed reaches the high value that air heater 3 set for, can automatic start protection disconnection power, protection air heater 3 can not burnt or the interior overtemperature phenomenon of drying shed, guaranteed safety, when the temperature in the drying shed drops to the low value that air heater 3 set for, protection device can restart air heater 3's fan and heater power again automatic start and continue to blow hot-blast to drying shed in, so, maintenance volume at ordinary times is fairly little, can not establish people on duty for a long time, saved the manpower.

Claims

1. A drying and finished product protecting device for a heater of a voltage stabilizer of a nuclear power station is characterized by comprising a drying shed consisting of an inner surrounding screen (1) and a surrounding screen (2), wherein the heater (6) is arranged at the top of the inner surrounding screen (1), the surrounding screen (2) is arranged on the outer side of the inner surrounding screen (1), the surrounding screen (2) extends upwards to the voltage stabilizer (5), and the top of the inner surrounding screen (1) is communicated with the surrounding screen (2); an air outlet hole (2-1) is formed in the peripheral screen (2), and an air heater (3) on the outer side of the peripheral screen (2) is communicated with the interior of the inner peripheral screen (1) through an air pipe (4).

2. Drying and end product protection arrangement for a nuclear power plant pressurizer heater according to claim 1, characterized in that the air duct (4) is arranged at the bottom of the drying shed.

3. A drying and finished product protection method for a heater of a voltage stabilizer of a nuclear power station is characterized in that the drying and finished product protection device for the heater of the voltage stabilizer of the nuclear power station is adopted, a hot air blower (3) is turned on, hot air blown out by the hot air blower (3) is blown into an inner surrounding screen (1), the hot air is blown to a heater (6) in a directional mode, and then the hot air is blown out of the outer surrounding screen (2) through an air outlet (2-1) of the outer surrounding screen (2).

4. A method for drying and protecting finished products of a heater of a voltage stabilizer in a nuclear power plant as claimed in claim 3, characterized in that the hot air blower (3) is provided with an over-temperature protection device, and when the temperature in the drying shed reaches the set value of the hot air blower (3), the hot air blower (3) automatically starts the over-temperature protection device and cuts off the power supply.