With the development regulation of metallurgical steel industry, the customer’s requires is higher and higher for the rolls materials and processing speed. The Wc/Tc roll rings, one of the hardest metal rolls, were widely applied high speed threaded rolling mill, of which processing speed usually gets above 75m/s and the highest speed gets 120~140m/s.
Cemented carbide (tungsten carbide) roll ring has high hardness, which beyond the hardness of traditional cutting inserts. The milling or turning Tc rolls ring mainly about adopt the superhard inserts, such as CBN inserts and the diamond cutting.
Turning Tc rolls ring: turning arts isn’t necessary for Tc rolls ring. Many manufacturers can directly choose grinding to repair them, but some manufactures can choose the turning arts. According to Tc rolls ring hardness, Processing Tc rolls ring should choose what kind of inserts material.
When the hardness
When the hardness >HRA88, the manufacture can choose the diamond inserts. The higher the hardness of the workpiece, the more brittle the material is. Therefore, be careful to avoid collapse inserts when turning the hard alloy (tungsten carbide) roller ring. We need to do chamfering in advance and accurately reserve working allowance.
At the same time, the cutting edge form of the turning insert is based on the hardness of the hard alloy (tungsten carbide) roll ring, the rigidity of the machine inserts and the past experience of user. The cutting edge form of the CBN insert is often E (passivated), S02020 (chamfered + Passivation is the mainstay, and the PCD tool cutting edge is often dominated by F (edge).
The Application Parameter of Processing Tc Mill Rolls ring with Solid CBN Inserts
(1) The Cutting Parameter of Processing Tc Rolls rings(HRA88): Adopting BN-S300, Cutting Parameter: Vc=15m/min，ap=1mm，Fr=0.3mm/r
(2) The Cutting Parameter of Processing Tc Rolls rings(HRA88): BN-S300 RNGN120400E , Cutting Parameter: Vc=20m/min，ap=0.5mm，Fr=1mm/r
Remark: BN-S300 grade belongs to solid CBN inserts. When turning the carbide (tungsten carbide) roll ring, it is recommended only for the roughing process within HRC88. In other cases, it is recommended to use the PCD/PCBN inserts.