Guide: Boiler, a high-efficiency equipment that can continuously provide heat energy, is an important common facility such as industrial production and people's daily use. Since it is a facility, it must be maintained and maintained, thereby increasing its service life and age, and reducing the frequency of damage. Number of times, what is the specific purpose of anti-corrosion after the gas boiler is out of operation? What are the methods for boiler shutdown maintenance?
Boiler, a high-efficiency equipment that can continuously provide heat energy, is an important common facility such as industrial production and people's daily use. Since it is a facility, it must be maintained and maintained, thereby increasing its service life and age, and reducing the frequency of damage. Number of times, what is the specific purpose of anti-corrosion after the gas boiler is out of operation? What are the methods for boiler shutdown maintenance? Reasons for anti-corrosion after boiler shutdown
Reason 1: The water film corrodes metal. After the boiler is stopped for a long time, the inner surface of the steam and water system pipes and the inner surface of the steam and water equipment in the boiler are often attached to a water film due to moisture. A large amount of oxygen in the air enters the boiler. It will dissolve in the water film and oxidize and corrode in contact with the metal surface.
Reason 2: Electrochemical corrosion. The boiler is made of metal. For this reason, slag or other debris will inevitably be deposited on the surface of the boiler in the past operation. These substances will absorb air and moisture and cause a water film on the boiler wall. In this way, electrochemical corrosion occurs due to the electrochemical inhomogeneity of the metal surface.
Reason 3:The corrosion of salt substances. The deposits on the boiler metal contain salt substances, which will dissolve in the water film on the metal surface and cause corrosion. This kind of corrosion is corrosion under scale.
Common maintenance methods for boilers
1. [Drying method], the temperature of the boiler water drops to 100-120 degrees Celsius, and the air valve is opened. After the water is drained, the waste heat of the boiler is used to dry the metal surface naturally, and then all the connecting valves are closed.
2. [Nitrogen filling method], after draining the boiler water, fill the boiler with nitrogen with a purity of more than 99%. Nitrogen is a protective gas. High-purity nitrogen prevents some objects from being oxidized by oxygen when exposed to the air. For this reason, it is applied to boiler maintenance.
3. [Desiccant method], this kind of desiccant is very common in daily life. There are many types, such as anhydrous calcium chloride, silica gel, quicklime, etc. The desiccant can remove part of the moisture in the moist material, so that the boiler will not The metal is oxidized due to high humidity.
4. [Maintenance of water supply pressure method], the boiler maintenance water supply pressure method is to fill the boiler with deoxygenated water and keep various valves closed during the period of inactivity. Take care to prevent freezing in winter.
5. [Vapor phase corrosion inhibitor method], the role of vapor phase corrosion inhibitor and desiccant is roughly the same, the main types are diammonium hydrogen phosphate, ammonium benzoate, and cyclohexylamine carbonate.
The above is an introduction to the reasons for anti-corrosion after shutdown of gas boilers and the common maintenance methods of boilers compiled by Xinli Boiler for your reference.