Performance Study of Carbon Dioxide–Based Vortex Tube Cooling System in Turning of Ti-6Al-4V

Abstract

A new cooling approach using a vortex tube and carbon dioxide (CO2) gas has been proposed in this work. This approach is developed to minimize the cutting temperature during the machining of titanium alloy. The cutting force, surface roughness, and cutting temperature are measured by varying input flow parameters such as pressure, cold fraction, and temperature of CO2 gas. This approach is observed to be better compared with dry cutting in reducing the cutting temperature and surface roughness. It is also observed that the cutting temperature and surface roughness are reduced with an increase in CO2 gas pressure and cold fraction and a decrease in CO2 temperature. Cutting force increased with a rise in the pressure and cold fraction and with a decrease in the temperature of CO2 gas. The response surface methodology is used to predict and optimize the cutting temperature, cutting force, and surface roughness, respectively. The validation of the results is carried out by performing the experiment at optimized input parameters.

Influence of flow parameters in the dual nozzle CO2-based vortex tube cooling system during turning of Ti-6Al-4V

“…The chemical composition and properties of the workpiece material are shown in Table 1 and Table 2. 29 The methodology of the current study was described in a flowchart presented in Figure 2. The turning operation is performed under the dry and VTCS environments at constant cutting conditions of speed, feed, and depth of cut whereas cutting force, cutting temperature, and surface roughness were the responses.…”

“…The levels of machining conditions were selected from literature and presented in Table 3. 29 The VTCS consists of a CO 2 gas cylinder, vortex tube with a controller, and a double nozzle setup as shown in Figure 3. The high-pressure gas is supplied to the vortex tube from the cylinder at required pressure.…”

“…By varying the controller, the ratio of the cold end outlet to the inlet flow is measured and calibrated for 0.1, 0.2, and 0.3 which indicates 10%, 20%, and 30% of the cold fraction, respectively. 29 Different diameters of the nozzles The responses such as F z , T m , and Ra values were measured by using a dynamometer (Kistler À5070), thermal imager (Fluke -TI400), and surface roughness tester (Surtronic -S128), respectively. When the gas was supplied by the vortex tube, its temperature decreases continuously and then reaches a steady state.…”

“…The levels of machining conditions were selected from literature and presented in Table 3. 29

Figure 1.Specifications of (a) tool holder and (b) cutting insert (all dimensions are in mm).

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“…The study revealed that the temperature gradient is increased with a reduction in nozzle number. Kumar et al 29 used a vortex tube cooling system (VTCS) during machining of Ti-6Al-4V and supplied cold-compressed CO 2 gas into the machining zone using a nozzle. This method improved the machinability in terms of cutting temperature and surfaceroughness.…”