High-boron steel, high-speed steel, and infinitely chilled cast iron rolls are widely used in the forming of wire rods, bars, and profiles. The roll pass has a great impact on the quality of finished products, mill productivity, equipment safety, and production costs. Therefore, in the machining process, the production requirements are also very high, so be careful when turning high-boron steel, high-speed steel, and infinite chilled cast iron roll grooves.
High-boron steel roll: high hardness, the value is HS75-80, ordinary roll machine tools and processing tools are not competent, ordinary pipe rolling machine tools are not rigid enough, the knife resistance is large during machining, and the vibration is severe, which affects the processing accuracy of the roll and the machine tool At the same time, processing high-boron steel rolls with general-purpose cutting tools will rapidly increase the wear of the cutting edge and flank, and the tool will be sharply passivated, making it impossible to process stably.
High-speed steel roll: the hardness is as high as HSD85-92, and it has good thermal stability. Intermittent cutting is more difficult to process, so choosing a reasonable processing tool and cutting amount is a prerequisite for determining whether the high-speed steel roll can be used normally on an online bar mill.
Infinite chilled cast iron roll: its surface is a white layer, but there is no obvious boundary between the white layer and the gray layer, and the hardness of the roll surface is HS ≥ 65. Because it is cast, there are especially large infinite chilled cast iron rolls on the rough edge surface. Casting defects, common cutting tools wear out sharply and cannot be processed stably.
In view of the performance of the above-mentioned high-boron steel, high-speed steel, and infinitely chilled cast iron rolls, three PCBN cutters are recommended for the groove process, namely BN-K1 grade, BN-S20 grade, and BN-S300 grade. When the groove surface quality of the roll is good If the machining surface has defects such as cracks and falling blocks, choose the BN-S20 grade. If the working conditions are harsh, choose the BN-K1 grade under strong intermittent cutting.
1. Case of high boron steel roll grooving
Processing material: high boron steel
Roll hardness: HRC68
Insert grade: BN-S20 RCMX-V series
Tool durability: 24 slots/cutting edge
2. Case of high-speed steel roll grooving
(1) Case of repaired rebar groove
Processing material: high speed steel; hardness: HRC64
Insert grade: BN-S300
Cutting parameters: Vc=40m/min, ap=0.5mm, f=0.5mm/r
Processing effect: the efficiency is 5 times that of carbide tools, and its durability is 4 times.
(2) Case of the repaired wire roll groove
Processing material: high speed steel roll, hardness: HRC63
Insert grade: BN-S300
Cutting parameters: Vc=26m/min, ap=2mm, f=0.5mm/r
Tool durability: 60min
3. Case of infinite chilled cast iron roll groove
Processing material: alloy infinite chilled cast iron
Roll hardness: HSD68
Insert grade: BN-K1
Cutting parameters: Vc=80m/min, ap=0.5mm, f=0.3mm/r
Processing effect: The efficiency of BN-K1 is 2 times higher than that of other brands carbide tools, and its durability is 7 times.