Maintenance safety technology of the hottest speci

Safety technology for special equipment maintenance

1. preparations before boiler maintenance

(1) before boiler maintenance, the boiler shall be shut down according to the normal shutdown procedure, cooled slowly, and the temperature in the boiler and furnace shall be gradually reduced by means of boiler water circulation and furnace ventilation. When the temperature of the boiler water drops below 80 ℃, open all kinds of door holes on the tested boiler. When opening the door hole, pay attention to prevent scalding by steam, hot water or smoke

(2) the steam, water supply, sewage and other pipelines on the tested boiler shall be separated from the corresponding pipelines of other boilers in operation. The blind plate used for partition shall have sufficient strength to avoid bursting by the high-pressure medium in operation. The partition position should be clearly indicated

(3) the combustion chamber and flue of the tested boiler shall be separated from the main flue or the flue connected with other operating boilers. The flue gate shall be tightly closed and ventilated after being cut off

2. precautions before pressure vessel maintenance

(1) before vessel inspection, the connecting pipeline between the vessel and other equipment with pressure or gas must be completely cut off, especially the access to equipment with combustible or toxic media. Not only to close the valve, but also use the functional characteristics of the tension machine 4 The instrument adopts brushless motor, and is equipped with overload protection and measurement principle. The blind plate is tightly closed to prevent the valve from leaking air, causing flammable or toxic gases to leak into the container, causing fire, explosion or poisoning accidents

(2) all the media inside the container should be drained. Containers containing flammable, toxic or asphyxiating media should also be cleaned, replaced or disinfected, and qualified after sampling analysis because natural bio based high molecular materials have the characteristics of green, environment-friendly, renewable and biodegradable materials that traditional high molecular materials do not have. The power supply related to the container, such as the power supply of the mixing device and turnover mechanism of the container, must be cut off, and there is an obvious indication sign that it is forbidden to turn on

3. Safety in maintenance. They also have excellent heat insulation performance and strong absorption capacity. Precautions

1) pay attention to ventilation and monitoring

before entering the drum and container, all the access holes on the drum and container and the hand holes on the header must be opened to allow air convection for a certain time and full ventilation. When entering the drum and container for inspection, someone must be outside the device for supervision. Ventilation must also be carried out before entering the flue or combustion chamber for inspection

2) pay attention to the safety of electricity

the lighting voltage should not exceed 24V when the electric lamp is used for lighting during the inspection in the drum and wet flue; In the relatively dry flue, and with proper safety measures, the lighting voltage not higher than 36V can be used. When entering the container for inspection, low-voltage explosion-proof lamps with a voltage not exceeding 12V or 24V should be used. When the power supply voltage of inspection instruments and repair tools exceeds 36V, flexible wires with good insulation and reliable grounding wires must be used. Open flame lighting is strictly prohibited in boilers and containers

3) it is forbidden to disassemble and assemble connecting parts under pressure

when inspecting boilers and pressure vessels, if it is necessary to remove or tighten the fasteners of pressure bearing parts, it must be carried out after the pressure is completely discharged. Bolts or other fasteners cannot be removed or tightened under the condition of pressure in the vessel, so as to prevent accidents

4) it is forbidden to replace the hydraulic test with the pneumatic test by yourself.

the pressure test of boiler pressure vessels generally uses water as the pressurized medium, and cannot use gas as the pressurized medium, otherwise it is very dangerous

individual containers cannot be subjected to pressure test with water due to structural and other reasons, and when the design stipulates that air pressure can be used to replace water pressure, the pressure test can be carried out only after comprehensive inspection, calculation of strength, and careful and reliable measures are taken according to the design regulations, and the consent of relevant safety departments should be obtained in advance