Defects in seamless steel pipes for boiler water-cooled walls are the result of a combination of internal factors of the seamless steel pipes and external factors of the boiler unit. Common defects in seamless steel pipes for boiler water-cooled walls include wear, corrosion, coking, and breakage. The main causes of defects in seamless steel pipes for boiler water-cooled walls include: 1) wear caused by fly ash; 2) corrosion caused by high temperature, excessive acidity, or excessive alkalinity; 3) cracking and breakage caused by uneven heating of the seamless steel pipes for water-cooled walls.
Analysis of common defect characteristics of seamless steel pipes for boiler water-cooled walls
(1) Coking in seamless steel pipes for boiler water-cooled walls. Coking is mainly due to the ash in the fuel melting into a liquid or softened state at high temperatures. Due to the heat absorption of the seamless steel pipes for water-cooled walls, the ash changes from a liquid or softened state to a solid state and is adsorbed onto the seamless steel pipes for water-cooled walls. Coking is related to fuel, boiler placement, flue gas, etc.
(2) Breakage in seamless steel pipes for boiler water-cooled walls. Damage is mainly caused by obstructed thermal expansion and stress concentration. The most common cause is excessive deviation in the internal heat load of the boiler unit, leading to thermal expansion and damage to the seamless steel pipes of the water-cooled wall. Damage is related to the design and installation of the boiler unit and the materials of the seamless steel pipes of the water-cooled wall.
(3) Corrosion of the seamless steel pipes of the boiler water-cooled wall. Corrosion is of two types: fire-side corrosion and water-side corrosion. Water-side corrosion is mainly caused by acidic and alkaline salts inside the seamless steel pipe, changing its pH value, resulting in the destruction of the metal protective film. Fire-side corrosion occurs on the outer wall of the seamless steel pipe. Under high temperatures, the incomplete reaction of the metal material with the CO generated by the coal corrodes the pipe wall. Corrosion is related to pH value, high temperature, and coal quality.
(4) Wear of the seamless steel pipes of the boiler water-cooled wall. Wear on the outer side of the seamless steel pipes of the water-cooled wall is mainly caused by the scouring of coal dust and fly ash. Wear is mainly related to coal quality and intake pressure.
Post time: Mar-16-2026