National standard steel pipes are made of steel ingots or solid tube billets through perforation to make capillary tubes and then made by hot rolling, cold rolling or cold drawing.

The raw material for rolling the national standard steel pipe is a round tube blank, which must be cut into a blank by a cutting machine, and then sent to the furnace for heating via a conveyor belt. The billet is fed into the furnace and heated at a temperature of approximately 1200 degrees Celsius.

The temperature control in the furnace is a key issue. After the round tube billet is out of the furnace, it is pierced through a pressure piercing machine. Generally, the more common piercing machine is the tapered roller piercing machine. This type of piercing machine has high production efficiency, good product quality, large perforation diameter expansion, and can wear a variety of steel types. After piercing, the round tube billet is successively cross-rolled, continuous rolled or extruded by three rolls. After squeezing, take off the tube and calibrate. The sizing machine uses a tapered drill bit to rotate at a high speed into the steel blank to punch holes to form a steel pipe. The inner diameter of the steel pipe is determined by the length of the outer diameter of the drill bit of the sizing machine.

After the national standard steel pipe is sized, it enters the cooling tower and is cooled by spraying water. After the steel pipe is cooled, it will be straightened. After straightening, the steel pipe is sent to the metal flaw detector by the conveyor belt for internal flaw detection. If there are cracks, bubbles, etc. inside the steel pipe, it will be detected. After the quality inspection of steel pipes, strict manual selection is required. After the quality inspection of the steel pipe, paint the serial number, specification, production batch number, etc. with paint. It is hoisted into the warehouse by a crane.

Specifications: The specifications of seamless steel pipes are expressed in millimeters of outer diameter * wall thickness.

Classification of national standard steel pipes: seamless steel pipes are divided into two categories: hot-rolled and cold-rolled seamless steel pipes.

Hot-rolled seamless steel pipes are divided into general steel pipes, low- and medium pressure boiler steel pipes, high-pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, geological steel pipes and other steel pipes.

In addition to general steel pipes, low and medium pressure boiler steel pipes, high-pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, and other steel pipes, cold-rolled seamless steel pipes also include carbon thin-walled steel pipes, alloy thin-walled steel pipes, and stainless steel pipes. Wall steel pipes, special-shaped steel pipes.

Huzhou Nanxun Yintuo Special Material Technology Co., Ltd., as a seamless pipe manufacturer, produces austenitic stainless steel seamless pipe and other types of seamless steel pipes. If you have any demand for purchase, please contact us.