Steel Pipe Annealing Heat Treatment Equipment Process

steel pipe annealing heat treatment equipment is special supporting thermal processing equipment matched with pipe production and deep processing lines, which is widely used in the standardized annealing production of carbon steel, low alloy steel, engineering machinery special pipe, seamless finished pipe and cold-drawn forming pipe. The core service goal of the whole set of equipment is to solve multiple adverse problems of steel pipes after rolling, cold drawing, stamping, welding and fixed-length cutting, such as uneven internal metallographic structure, residual mechanical internal stress, overhigh local hardness and poor follow-up processing performance, and lay a stable performance foundation for subsequent pipe bending, hole expanding, finish turning, thread rolling and assembly matching construction.

The mainstream supporting equipment on site is medium-frequency induction annealing integrated unit and continuous roller sealed annealing furnace, with closed-loop constant temperature control system and circulating water cooling protection system for heating components. The overall process is carried out in a fully closed or semi-closed heat preservation inner tank, which can effectively isolate external cold air, reduce surface oxidation of pipe bodies, avoid peeling of oxide scale, and keep the original smooth flatness of the outer wall of finished steel pipes. Compared with traditional box-type intermittent heating equipment, the special annealing heat treatment equipment for pipes features uniform circumferential heating of round pipes, small temperature difference between inner and outer walls, low comprehensive energy consumption and uninterrupted assembly line operation, which fully meets the mass production rhythm of mechanical pipe supporting factories.

The standard technological process is divided into four core links in sequence: feeding pre-alignment, segmented constant temperature heating, constant temperature heat preservation and controlled slow cooling. Before formal heating, the equipment automatically sorts and arranges materials to remove surface oil stains, iron chips and sundries, preventing local overheating and burning defects during heating. In the heating stage, the equipment accurately raises the temperature to the standard annealing interval of 550℃ to 850℃ according to different pipe wall thicknesses and steel grades, and the intelligent temperature control system keeps the temperature fluctuation within ±5℃ to ensure consistent heating quality of each batch of pipes. The heat preservation link is matched with the wall thickness ratio to fully release structural stress and refine internal metal grains, eliminating processing hardening thoroughly.

The key core of the equipment process lies in the simulated furnace slow cooling linkage system. It strictly forbids forced rapid cooling. The whole cooling process is completed at a uniform low speed inside the equipment to prevent secondary stress, pipe body bending and wall surface cracking. After annealing by this set of heat treatment equipment, the hardness of steel pipes is moderate and uniform, the internal structure is compact and stable, the toughness and plasticity are significantly improved, and the yield and qualification rate of finished products are effectively guaranteed. The whole process is simple to operate, safe and stable in long-term operation, and is the essential supporting equipment for high-quality production of engineering steel pipes.

pipe induction annealing machine