Setting measures for the hottest safety door

2022-10-14
  • Detail

Safety door setting measures

1.1 code for startup and completion acceptance of capital construction projects in thermal power plants (2009 Edition)

1.2 code for construction and acceptance of electric power construction

1.3 standard for quality inspection and evaluation of commissioning and commissioning of thermal power projects

1.4 regulations on quality supervision of power capital construction projects

1.5 regulations on startup and commissioning of thermal power projects

1.6 regulations on safety work in electric power construction

1.7 equipment instructions and technical agreements of relevant manufacturers

2 preparations before safety valve adjustment:

2.1 boiler tightness test is over

2.2 the safety valve must be ground and tested for oil leakage

2.3 the safety valve shall pass the hydraulic test

2.4 the drainage pipe of the safety valve should be firm and does not affect the expansion

2.5 prepare necessary communication equipment (Interphone or), prepare two 0.4 standard pressure gauges with a range of 0 ~ 4MPa, and one 0.4 standard pressure gauge with a range of 0 ~ 1.6Mpa. With the further development of manufacturing and material industry, the local pressure gauge and control room pressure gauge must be calibrated

2.6 temporary lighting should be installed around the safety valve, the road should be unobstructed, and non adjusting personnel should not be close to the safety valve

2.7 prepare various tools, paper, pens, etc. for adjustment

2.8 special personnel shall make records and the data shall be accurate

2.9 all adjustment personnel should understand and organize the implementation of the measures to adjust the safety valve, with a clear division of labor

3 safety valve verification

3.1 safety valve setting value

drum safety valve control pressure unseating setting value: 1.80, 1.81, 1.82, 1.83mpa

hot return water safety valve control pressure unseating setting value: 0.385mpa

3.2 when the take-off pressure exceeds the setting pressure, it should reach the specified safety valve opening height, and the opening height is not allowed to have negative deviation. The reseating differential pressure of the safety valve shall not be greater than 3% of the respective set pressure

3.3 methods and steps of safety valve calibration: (tentative)

3.3.1 the operator adjusts the water pressure, stabilizes the drum pressure at 70% of the rated pressure, and pays attention to maintaining the pressure rise speed during the pressure rise of the boiler

3.3.2 before the test, when the pressure rises to 0.5MPa, carry out a manual pre seating test on each safety valve, check the lifting height of the valve and purge the garbage to confirm that it is flexible and tight to seat up and back

3.3.3 when the water pressure rises to the required value, stabilize the pressure, and check the local water pressure indication with the water pressure indication in the main control room to determine the error

3.3.4 install the safety valve that is not subject to calibration on the compression device

3.3.5 when the water pressure meets the requirements, install the safety valve calibration hydraulic device on the safety valve to be calibrated as required, and then gradually boost the pressure with the booster pump. When the safety valve makes a "hissing, hissing" sound, record the hydraulic value and local pressure at this time, and immediately relieve the pressure to prevent the safety valve from jumping

3.3.6 calculate the take-off pressure. If it fails to meet the set pressure requirements, adjust the spring compression nut according to the deviation and repeat the above operations until two standards of the take-off pressure have been approved by the national standards committee to meet the requirements

3.3.7 calibrate the safety valves one by one according to the above steps, and the calibration sequence is from high to low according to the set pressure

3.3.8 when calibrating the safety valve, the continuous test pressure shall not exceed 3 times, otherwise the calibration accuracy will be affected due to the heating of the components

3.3.9 actual take-off test of safety valve. Select the safety valve for the test jump. When the safety valve is tested, press other safety valves with clips, and release all clips after all are calibrated

3.3.10 apply for a visa after the safety valve passes the calibration

(the specific test method should be determined by the safety valve manufacturer, guide the operation adjustment parameters to meet the requirements of the safety valve manufacturer, and cooperate with the manufacturer to set the safety valve)

4 division of labor

4.1 the commissioning unit is responsible for formulating commissioning measures and organizing the implementation

4.2 the construction unit is responsible for the maintenance, overhaul and defect elimination of equipment and systems during commissioning, as well as the production, installation and system recovery of temporary facilities

4.3 the production unit is responsible for operation and other work under the guidance of commissioning personnel according to commissioning measures and operation procedures

4.4 the equipment manufacturer shall go to the site to provide technical services and guidance according to the contract requirements, and eliminate equipment defects as soon as possible

4.5 the construction unit coordinates the working relationship of all relevant units, establishes various working systems, and urges all relevant units to complete their own work

4.6 supervision unit: participate in the whole process of unit commissioning, complete the supervision work, and be responsible for the whole process of the project. Be responsible for the statistics, summary, classification and nature determination of equipment defects

5 safety precautions

5.1 when the safety valve is under pressure, don't hit it to lead the continuous development of the industry, otherwise it may act without taking off pressure

5.2 when working on pressure bearing safety valves, necessary protective tools should be used

5.3 do not stand at the water outlet of the pressure bearing safety valve

5.4 the pressure gauge should be read by a specially assigned person

5.5 when trying to jump the safety valve, except for the safety valve to be tested, other safety valves of the system should be clamped. In order to prevent the thermal expansion force from acting on the door shaft, the system pressure should reach 70% of the set pressure before pressing the safety valve

5.6 when the safety valve needs to be adjusted, the system pressure must be reduced to less than 10 ~ 20% lower than the actual take-off pressure of the safety valve

Copyright © 2011 JIN SHI