Corrosion issues of Incoloy800HT
Thread Content
We have a furnace; the shielding tubes in the convection section are made of Incoloy 800HT. After about four years of use, it has been found that one of these tubes has a hole measuring 6–7 cm in diameter. The surfaces of the other furnace tubes are covered with sulfur deposits. After removing those deposits, pitting corrosion was observed on the surface of those tubes, with uniform pits appearing on their surface. The thickness of the areas on the tube surfaces that remain intact is normal. The medium inside the furnace tube is low-pressure steam, with a steam temperature of 630°C and a pressure of 0.3 MPa ； The flue gas temperature outside the furnace tube is 800℃ ； The furnace uses a gas-oil mixed combustion fuel. Dear experts in this field, please help analyze it. Thank you!
Great picture sharing! ! ! ! Is the corrosion and scarring of the furnace tubes caused by the fuel gas? ? ?
Should I replace it with a new one? I work with nickel-based alloy materials here
Incoloy 800HT generally should not be exposed to temperatures above 860 degrees; check whether there is any over-temperature condition. If not, verify whether the nickel content in the material is too low