Boiler safety valve setting measures 1. Preparation before safety valve adjustment:
1. Perform visual inspection of the safety valve. Look at the presence or absence of cracks, and then perform spectral analysis on the material of each component, which should meet the design requirements. Check the weld port and the screw joints of the safety valve body for abnormal conditions. If there are cracks at the weld joint and the screws do not meet the specifications, they should be treated in advance.
2. The steam pressure gauge and superheater on-site pressure gauge and digital pressure gauge are qualified (the local pressure gauge can be installed with standard pressure gauge when adjusting).
3. Prepare debugging tools and communication tools (such as walkie-talkies, etc.).
4. The ignition valve and the accidental drain valve should be tested normally and easily.
Second, the safety valve operating pressure regulation safety valve adjustment pressure is determined according to the "Technical Standards for Power Generation Enterprises" in the power construction construction and acceptance technical specifications (boiler unit articles), take 1.04 times the working pressure for the control of the safety valve The operating pressure is 1.06 times the working pressure of the working safety valve. The opening and closing pressure difference is 4%-7% of the opening pressure, and the Zui is not more than 10%. Superheater control safety valve opening pressure: 3.82×1.04=3.97MPа
Return pressure: 3.81—3.69 MPа zui low 3.58 MPа
Superheater working safety valve opening pressure: 3.82×1.06=4.05 MPа
Back pressure: 3.88—3.77 MPа zui low 3.64 MPа
Drum control safety valve opening pressure: 4.3 × 1.04 = 4.47 MPа
(one each on the left and the right)
Reseat pressure: 4.29—4.16 MPа zui low 4.02 MPа Drum work safety valve opening pressure: 4.3×1.06=4.56 MPа
Return pressure: 4.38-4.23 MPа zui low 4.10 MPа
3. After the boiler is running normally, the safety valve can be directly set. The order of setting is:
1, steam drum work safety valve
2, steam drum control safety valve
3, superheater outlet header working safety valve
4. Superheater outlet header control safety valve 4. Setting method:
1. Press the non-adjusting safety valve with the ejector pin (or the compression nut).
2. Switch the ignition exhaust valve from electric control to on-site manual control before setting.
3. Adjust the steam pressure of the combustion and ignition exhaust valves to make it rise slowly. When the pressure is close to the operating pressure, the pressure should be kept stable and slowly rise to the setting pressure. If the seat pressure is not exceeded, the ignition row should be turned on in time. Steam valve, reduce the steam pressure of the boiler, or use the handle on the valve stem to force the steam to reduce the pressure, adjust the opening pressure, and try again.
4. After the seat is opened, it is necessary to monitor the pressure of the seat back to facilitate the adjustment of the seat back pressure.
5. When the pressure meets the requirements, do another test.
6. After adjusting one, adjust the next one.
V. Other requirements:
1. The air exhaust valve can be used for pressure adjustment.
2. When approaching the opening pressure, be sure to slowly increase the pressure.
3. When adjusting the safety valve, the monitoring of steam temperature, steam pressure and water level should be strengthened.
Care should be taken to minimize the number of movements of a single safety valve.
4. The adjustment pressure of the safety valve of Sanjing Valve Co., Ltd. is based on the local pressure gauge. The pressure of the seat and the pressure of the seat should be carefully recorded in detail.
5, to ensure that the personnel on the furnace and the control room personnel communication is smooth.
Sixth, safety precautions:
1. Before setting, check the installation and support of each exhaust pipe.
2. Temporary platform should be set up at the safety valve.
3. Before the safety valve is adjusted, it must be operated under a period of underpressure after returning to the seat.
4. Participation in adjustment personnel should have measures such as anti-noise earplugs.
5. Before adjusting the safety valve, it should be fully checked whether the safety valve system is installed correctly, whether the exhaust pipe installation is firm and whether it affects expansion.
6. Before adjusting the safety valve, all high-altitude operations in the plant should be stopped. Non-workers should not enter the top of the furnace, and should not be close to the exhaust pipe.
7. The road where the safety valve is located should be smooth, with sufficient lighting and reliable communication facilities. Any place with temporary scaffolding must have railings to prevent accidents from falling from height to ensure personal safety. In the process of adjusting the safety valve, if an accident occurs. The calibration should be stopped.
Seven, calibration work arrangements:
The verification test work is organized by the operation workshop. The operation workshop is responsible for operation, recording and on-site liaison work. The maintenance workshop is responsible for the adjustment of the safety valve and the on-site guidance of the production department.