Metal Machining With High-Pressure Water-Jet Cooling Assistance—A New Possibility

Abstract

Metal machining is one of the fundamental manufacturing processes. The principal cost of shaping metal parts is generated both in the work involved in shearing metal from the original stock, at the area where the chips are formed, and also in the work required to overcome the high frictional forces that exist between the chip and rake face. Current techniques for the lubrication and cooling of this area are not very effective, resulting in a machining cost which is much higher than need be. A more efficient lubricooling effect can be achieved by the use of a high-pressure water jet directed into the tool/chip interface. The study of this idea was prompted by results achieved in the 1950’s, but now extended to much higher jet injection pressures (up to 280 MPa). The emphasis of this article is on the comparison of the coefficient of friction at the tool/rake interface for conventional and high-pressure jet cooling and also on reporting some practical results. Evaluation of these results indicates both a significant gain in the material removal rate as well as an improvement in the chip shape. The results are for a UNS 1020 steel—a representative of the poorly machinable materials.

Wear behavior of uncoated carbide inserts under dry, wet and cryogenic cooling conditions in turning C-60 steel

“…Recently in 1997, in high speed machining of inconel and titanium alloys, cutting fluids failed to reduce cutting temperature and improve tool life effectively (Kitagawa et al 1997). However high pressure jet of soluble oil, if applied at the chip-tool interface, could reduce cutting temperature and improve tool life to some extent (Mazurkiewicz et al 1989). In machining ductile metals even with cutting fluid, the increase in cutting velocity reduces the ductility of the work material and causes production of long continuous chips, which raises the cutting temperature further (Nedess and Hintze 1989).…”

The Effects of a High-Pressure Coolant Jet on Machining

“…Some workers have applied the jet between the clearance face of the tool and the workpiece (1, 2), while others have applied it between the rake face of the tool and the chip being formed (3,4) or forced it directly into the chiptool interface through a small hole in the rake face of the tool (5). The objective of all these investigations was to improve machinability by helping the cutting fluid to reach as close as possible to the critical point on the secondary shear zone and thus allow the fluid to exert its lubricant and coolant functions more eficiently.…”

Modeling the Correlation Between Cutting and Process Parameters in Machining of NI Based Udimet Alloy Using Artificial Neural Network

“…There was a steady reduction in cutting force with increase in pressure (Fig. 6 (b)) due probably to reduction in the toolchip contact length due to the hydraulic wedge created by the HPC jet at tool-chip interface [19]. A slight increase in feed force was obtained when the pressure increased from 110 tp 150 bar followed by a rapid reduction when the pressure increased from 150 to 210 bar (Fig (c)).…”