TPT March 2018

AR T I C L E

Shandong Province SiFang Technical Development Co, Ltd

Manufacturing process

Grade

Roll category

Recommended application

GCr15

9Cr2Mo 9Cr2MoV Cr12 3Cr2W8V

Apply to small diameter, thin wall, ordinary rolling material, low accuracy, small batch, small deformation force, low rolling speed.

Forming roll, sizing roll, straightening roll, assembly side squeezing roll and bottom squeezing roll

Two roll squeezing roll, assembly top squeezing roll

9Cr2Mo

Also can be applied to large diameter rolling material but wear resistance is lower than the brands listed below.

Forging roll

Forming roll, sizing roll, straightening roll assembly side squeezing roll and bottom squeezing roll

9Cr2MoV

Cr12Mo1V1

Forming roll, sizing roll, straightening roll assembly side squeezing roll and bottom roll

Cr12MoV

Apply to all kinds of service conditions, especially for large diameter, thick wall, high grade steel, seamless steel rolling material, high accuracy, large batch, huge deformation force, high rolling speed.

4Cr5MoSiV1

Two roll squeezing roll, assembly top squeezing roll

ZCr15

Breakdown roll

Precision forming roll, sizing roll, straightening roll, assembly side squeezing roll and bottom squeezing roll

Casting roll

ZCr20

ZCr25

Two roll squeezing roll, assembly top squeezing roll

Table 16 : Recommended application of rolls

shapes, whereas cast forming can be single roll. This guarantees the application quality, simplifies the structure and is easy to assemble. There is currently an unprecedented level of development and progress in roll manufacturing. The process and technology for rolling steel is also changing along with the upgrading of rolling steel facilities. Only by focusing on technology progress can companies survive in such a competitive and changing market.

The best indicator for performance is not the price of the rolls, but the roll consumption amount when rolling the same products per ton. 5.2 The application scope of rolls for welding steel pipe The Chinese national standard GB/T 31936-2015 ‘Rolls for welding steel pipe’ appendix A illustrates the recommended application of all kinds of rolls and is a good reference point. 6. Conclusion The development of rolling mills is leading to larger factories working at higher speed and higher levels of automation to meet the requirements of rolling material for high accuracy and high roughness. It is also accelerating the upgrading of roll material and the improvement of the manufacturing process. Improvements to the alloy content of rolls is one of the most efficient ways to improve the property of rolls. Since new casting processes and advanced facilities are gradually developed, high alloy content and high performance casting rolls will be produced. Casting high-speed steel rolls makes using centrifugal casting techniques that continuously pour the outer layer cast (CPC) more likely. The process is developing faster than ever and is benefiting from extensive research. The change in manufacturing processes has also caused changes to the roll shape and structure in some cases. A lightweight ‘breakdown’ roll for large-scale mills is now possible for casting, while for forging it is still impossible. Forging mainly uses assembly rolls used for forming complex

Shandong Province SiFang Technical Development Co, Ltd – China Tel: +86 531 88881980

Email: sdsf@vip.163.com Website: www.cnsdsf.com

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MARCH 2018