Welding method for overhaul of furnace chamber heat exchange tube

Abstract

The invention discloses a welding method for overhaul of a furnace chamber heat exchange tube, comprising a butt joint A, a butt joint B and a butt welding line, a cover board is arranged between the butt joints tangentially, an inner beveled edge with a certain angle is milled at the joint edge position of the butt joint A and the butt joint B, the contact parts of the cover board and the butt joints are respectively milled into outer beveled edges with a certain angle; the butt joint A and the butt joint B are assembled, the butt welding line is welded, and then the cover board and the cover board welding line at the joint position are assembled, after welding is carried out, and the welding is qualified through nondestructive examination, banding and heat treatment are carried out to the whole welding line and are qualified, system pressure test is carried out; when in construction, the heat exchange tube does not need to be changed in a large area, after defect part is examined, the heat exchange tube is changed locally by adopting the method, before construction, standard and interchangeable joints and the cover board can be machined according to pipe diameter, material quality and specification and the like by a drawing after the defect part is examined, the operability is strong, the overhauling efficiency can be greatly improved and the quality is ensured simultaneously.

Description

technical field [0001] The invention relates to a welding method for overhauling furnace heat exchange tubes, which is suitable for overhauling furnace heat exchange tubes of chemical boilers and gasification furnaces. Due to the narrow environment for overhauling, the heat exchange tubes do not need to be replaced or cannot be replaced as a whole, but must be partially replaced. It is inconvenient to apply welding on the surface during replacement. Background technique [0002] Existing heat exchange tubes in boilers, gasifiers and other furnaces operate under high temperature, high pressure, and high stress conditions for a long time. During long-term high temperature and high load operation, partial leakage of equipment often occurs and needs to be shut down for repair. Grinding and surfacing are often used for repairing, and methods such as overall replacement are used for large-scale damage, especially heat exchange tubes that cannot be replaced or repaired as a whole, ...

AI Technical Summary

Problems solved by technology

Grinding and surfacing are often used for repairing, and methods such as overall replacement are used for large-scale damage, especially heat exchange tubes that cannot be replaced or repaired as a whole, and the inspection environment is narrow, and surface welding cannot be performed normally, which affects the quality of repairs and makes the repair cycle long, affecting the normal and stable operation of production

Images