Hot rolled (extrusion seamless steel pipe): round tube → heating → perforation → → three-roll rolling, rolling or extrusion → detached → sizing (or reducing) → cooling → straightening hydraulic test (or flaw) → tag → storage.

A rolling seamless tube of raw materials is a round tube, tube embryos go through a cutting machine to cut the growth of the degree approximately 1 meter, and are sent by conveyor belt furnace heating. The billet is fed into the heating furnace, the temperature is about 1200 degrees Celsius. Fuel for hydrogen or acetylene. The furnace temperature control is critical to wear air tube round, after the release of the pressure puncher. which are generally more common puncher tapered roller punch this punch, high production efficiency, product quality, perforated expanding volume, wearing a variety of steels. After perforation, the round tube has been three-roll cross rolling, rolling, or extrusion. After extrusion off pipe sizing. Sizing mill by the high-speed rotation of the cone drill into the Billet punch to form a steel pipe. The steel pipe inner diameter is determined by the length of the outer diameter of the sizing mill drill. After sizing, the steel pipe to enter the cooling tower by the water spray cooling, the steel pipe after cooling, it is necessary to be straightening. Sent by conveyor pipe by straightening the metal detection machine (or hydrostatic test) to conduct an internal flaw. Steel pipe internal issues such as cracks, bubbles will be detected. Steel pipe quality inspection but also through a rigorous manual selection. Steel pipe of Quality Supervision, Inspection, use spray paint on the number, size, production batch. By a cable car hanging into the warehouse.