Thick-walled seamless pipes can be divided into three categories according to production methods: hot rolling, welding and cold processing. Hot-rolled seamless steel pipe is a steel pipe in which a solid tube blank or steel ingot is perforated and rolled into a hollow section. The basic process is perforation and tube rolling. Cold-processed seamless steel pipe is the secondary processing of steel pipes (also includes the secondary processing of thick-walled seamless pipes and thin-walled seamless steel pipes). Cold working is an important method to obtain high-precision and high-performance pipes, including cold rolling, cold drawing, cold tension reduction and cold spinning, etc.
The raw material for large-diameter thick-walled seamless pipes is round tube billets. The production process is as follows: the steel billets are fed into the furnace and heated to a temperature of approximately 1,200 degrees Celsius. The fuel is hydrogen or acetylene. Temperature control in the furnace is a key issue. After the round tube comes out of the furnace, it must be pierced through a pressure punching machine. The most common punching machine we use is a tapered roller punching machine. After perforation, the round tube blank is successively cross-rolled, continuous rolled or extruded by three rollers. After extrusion, the pipe must be removed and calibrated. The sizing machine uses a conical drill bit to rotate at high speed into the steel blank to drill holes to form a thick-walled seamless pipe. The inner diameter of the thick-walled seamless pipe is determined by the outer diameter length of the drill bit of the sizing machine.
The thick-walled seamless pipe enters the cooling tower, and the steel pipe is sized. Through water spray cooling, the steel pipe will be straightened after cooling. After straightening, the steel pipe is sent to the metal flaw detector (or hydraulic test) by the conveyor belt for internal flaw detection. If there are cracks, bubbles and other problems inside the steel pipe, they will be detected. The finished thick-walled seamless pipes must undergo strict manual selection after quality inspection. After quality inspection personnel pass the quality inspection of thick-walled seamless pipes, we spray paint on them with serial numbers, specifications, production batch numbers, etc. It is lifted into the warehouse by a crane.
Seamless pipe process
Sanitary mirror pipe process flow: Tube blank - inspection - peeling - inspection - heating - perforation - pickling - grinding - lubrication and air drying - welding head - cold drawing - solution treatment - pickling - pickling passivation - inspection - cold Rolling - degreasing - cutting - air drying - internal polishing - external polishing - inspection - marking - finished product packaging
Industrial pipe process flow: tube blank—inspection—peeling—inspection—heating—piercing—pickling—repairing—lubrication and air drying—welding head—cold drawing—solution treatment—pickling—pickling passivation—inspection
Seamless pipe processing process uncoiling - flattening - end shearing and welding - looper - forming - welding - internal and external weld bead removal - pre-correction - induction heat treatment - sizing and straightening - eddy current testing - cutting off - hydraulic pressure inspection - acid Washing - final inspection - packaging
