Page 58 - Towards A Sustainable Future 2024

Each CNC machine uses two pumps to circulate coolant
effectively. One pump directs coolant onto the workpiece
and cutting tool, ensuring efficient cooling and lubrication.
The second pump removes chips created during machining
by circulating coolant on the cutting area’s side. This
dual-pump system optimises coolant flow and enhances
machining efficiency.

By addressing these environmental concerns, DM
Engineering can improve its environmental performance
while maintaining operational efficiency and product Figure 4: Back of CNC machine with 2 coolant pumps
quality. Figure 4 shows the picture of the two pumps at the
back of each CNC machine.
Figure 5: Shows the coolant nozzles that blown onto the
workpiece and cutting tools to remove the metal chips.
The power rating of each pump = 1.1A X 240V = 264w. There
are 26 pumps used in all 13 CNC machines, and the power
rating for all 26 pumps is 264w X 26 = 6864 w. Considering the
machines ran for 10 hours daily, the daily power consumption
is 6864w X 10, which is 68640Wh or 68.640kWh. The daily,
monthly and annual power consumption for all 26 pumps is
shown in Table 1:

Daily (kWh) Monthly Annual (kWh)
(kWh)

68.64 1372.8 16473.6

Table 1: Daily, monthly and annual power consumption Figure 5: Coolant nozzles
for 26 coolant pumps.
The used coolant flows from the machining area into the
coolant reservoir, filtered through a mesh to remove the
The annual power consumption converted to carbon using chips and recirculate again. Oil, is removed with a skimmer
the conversion rate (0.4057kg CO2/kWh) is 16473.6 X 0.4057, machine. Figure 6 shows the coolant reservoir and the
6,683.33kg of CO2. skimmer machine where the lubricant is removed. Figure
7 shows the mesh used to remove the metal chips during
cutting.

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