High Feed Machining – Science of High Metal Removal Rate

Detailed Specification

We are amid the fourth industrial revolution (Industry 4.0). The manufacturing industry is bracing new technologies, helping them in improving machine utilization. CNC mills and CNC lathes are being built to perform metal cutting operations at never before speeds. As a cutting tool partner, Tungaloy has enjoyed developing equally good metal cutting tools for these new generation CNC mills and lathes.

The three most important parameters to form a chip out of parent material are:

• Cutting speed (Vc – meters/min or SFM)
• Feed (Fz – mm/rev or Inch / rev)
• Depth of cut (DOC – mm or inches).

All three when applied at the right proportion, based on the material being cut, produce the most desirable chip. Optimizing the three to gain the optimal Metal Removal Rates (MRR – cc/min or cf/min), has been the endeavour of every tool engineer. This is the way to improve the utilization of a complex CNC mill or a CNC lathe.

High Speed vs. High Feed & better utilization of CNC mills and lathes

In the middle of the last century, HSM (High-speed machining) evolved as a metal cutting process, which suggests beyond a certain cutting speed the heat generation starts declining. HSM employs high spindle speeds and high table feeds, taking shallow cuts. This was a big change in the way metals were processed into complex parts. With the development of more complex CNC milling machines and CNC lathes, the cost of such machines also escalated.

• From low to moderate speed machines able to run at about 3000 – 6000 spindle RPM, machines evolved into having over 12,000 to 20,000 RPM spindle speeds.
• From 02 – 03 axis machines, CNC machines with multi-axis were introduced
• With the simultaneous working of the axis, producing more complex parts became a reality, supported by more intelligent software and hardware.
• Compact-sized machines were introduced to produce components, which were earlier being processed on much bigger CNC lathes and mills.
• By utilizing HSM, smaller diameter tools started being used in place of large diameter tools.

However, HSM became and still remains popular for finishing operations of tough to machine materials and hardened steel. HSM yielded better results with surface quality and profile machining operations, which required blending of fine curves to improve the aesthetics of the machined part, however, it has not been popular as a process for roughing to semi-finishing operations. HSM also remained popular for use with smaller diameter tools and end mills, mostly on hardened steels, especially carbide ball and bull nose end mills.

What still remained a challenge was reducing the processing time in roughing and semi-finishing operations.

Tungaloy has been in the forefront of developing innovative solutions for High Feed Machining (HFM). It has championed this process of machining, equally well in turning, milling and grooving applications.

Read more about Industry 4.0 and see how Tungaloy is at the forefront of this evolution HERE