Eventos Anais de eventos
COBEM 2017
24th ABCM International Congress of Mechanical Engineering
Effects of MQL on Workpiece Temperature and Hole Quality in Deep drilling of SAE 4144M Steel
Submission Author:
Milton Polli , PR
Co-Authors:
Marlon José Cardoso, Milton Polli
Presenter: Milton Polli
doi://10.26678/ABCM.COBEM2017.COB17-0635
Abstract
Drilling of deep and small boreholes using twist drills is a challenging task due to difficult chip removal and accumulated heat during the process. Pressurized fluids are often used to overcome these problems, however they add costs to the process, increase the environmental impact and represent occupational health risks. Minimum quantity lubrication (MQL) is a more ecological alternative to conventional flood cooling, however it has limited effect in terms of cooling the cutting edge and chip evacuation. This study compares MQL and conventional lubrication condition in deep drilling taking in consider the workpiece temperature and hole quality. The workpiece material is SAE 4144M forged quenched and tempered steel with hardness of 39 HRC. Solid cemented carbide drills with 4 mm diameter were used to drill 96 mm depth holes. A single channel unit was used as minimum quantity lubrication system. LubriOil E47 was selected for MQL tests, the pressure in the pipeline was 10 bar and oil flow rate was approximately 20 ml/h. EcoCut 610B pressurized to 50 bar was used in flood application tests. The results showed that the workpiece temperatures are higher for MQL in comparison to pressurized oil condition. There was a small variation of the hole diameter, however it was possible to observe that values were higher for the MQL condition. Roundness values were higher for MQL and surface roughness values were close for the both lubrication conditions.
Keywords
MQL, Drilling, Twist drill
