The difference between hot-rolled and cold-rolled seamless pipes
As an important part of steel products,steel pipes are divided into two categories,seamless steel pipes (round billets) and welded steel pipes (plate with blank) because of their different manufacturing processes and the shape of the pipe blanks used.Because of its different manufacturing processes,seamless steel pipe is divided into hot-rolled (extrusion) seamless steel pipes and cold drawn (rolled) seamless steel pipes.
The difference between hot-rolled and cold drawn seamless pipes:
- From the processing point of view, hot rolling is hot processing, cold drawing is cold processing. Hot rolling is rolling at a temperature above the re crystallization temperature, and cold rolling is rolling at a temperature below the re crystallization temperature;
- The diameter of seamless pipe hot rolling is generally greater than 32mm,thickness 2.5-75mm,cold-rolled seamless steel pipe diameter to wall thickness to 6mm,0.25mm to 5mm,the thin-walled tube diameter,wall thickness is less than 0.25mm,cold than hot rolled high precision.
- From the appearance to distinguish cold-rolled seamless steel pipe surface bright, caliber size is smaller than hot-rolled seamless steel pipe.The hot-rolled seamless steel pipe has a larger caliber than the cold- rolled seamless steel pipe, and the surface has obvious scale or red rust.
- Hot-rolled steel pipe used in fluid transport, mechanical structure and other requirements for size is not high; cold-rolled steel pipe used in equipment, hydraulic systems, pneumatic and other places where high requirements.
- In terms of wall thickness,cold drawn seamless tubes are more uniform than hot rolled seamless tubes. It is sent to the automatic rolling mill for inherited rolling.
Haihao Group manufacture hot rolled and cold drawn seamless steel pipes more than 30 years,if you are interested in our products,please contact us email:email@example.com