Evaluation of mist flow characteristic and performance in Minimum Quantity Lubrication (MQL) machining

Minimum Quantity Lubrication (MQL) is an alternative method to supply the cutting fluid in the formation of mist. MQL has proven to reduce machining cost and increase machining performance. The effectiveness and the working principle of MQL are still questionable with very few explanations provided. The present study is conducted to investigate the performance of MQL technique with different combination of spray and machining parameters. The Phase Doppler Anemometry (PDA) was used to characterize the lubricant spray under different input pressure for various nozzle outlet diameter of 2.5 mm (OD25) and 3.0 mm (OD30). This device can measure the amount of droplet and size. From these results, the distance of the nozzle to the cutting tip can be estimated. The turning performance in terms of cutting force and cutting temperature was evaluated under three levels of cutting speed and two levels of feed rate and at a constant depth of cut. The result shows that the most suitable mist flow pattern during machining was the largest spray cone angle supplied under 0.4 MPa input air pressure. In addition, significant reduction of cutting force and cutting temperature were obtained when using OD30 nozzle at the nozzle distances of 6–9 mm and the input air pressure of 0.4 MPa

An analysis of surface integrity when drilling inconel 718 using palm oil and synthetic ester under, MQL condition

The components being manufactured in the aerospace industry must be capable of being utilized for long periods without failure. Thus, the functional behavior of these machined components is greatly dependent upon their surface integrity. The present work compares the performance of palm oil and synthetic ester on surface integrity during drilling of Inconel 718. The results indicate the substantial benefit of the minimum quantity of lubrication (MQL) by palm oil on microhardness, surface roughness, surface defects and sub-surface deformation

Simulation and experimental study of double holes film cooling

In the modern gas turbine, film cooling has been widely used to provide thermal protection for the external surface of the gas turbine blades. Numerous number of geometrical arrangement film cooling have been presented for the past 50 years. The main inspiration of the presented geometrical arrangements film cooling are to minimize the effect of lift off phenomena caused by the formation of the Counter Rotating Vortex Pair (CRVP) which commonly discovered in the Single Cylindrical Hole (SCH) arrangement. In order to reduce the CRVP effects, tremendous efforts from the past researchers have been made including the introduction of the Double Cylindrical Hole (DCH). The present study has made use this DCH along with the employment of several geometrical arrangements including pitch distance (POD), length between holes in streamwise direction (LoD), compound angle and upstream ramp. The evaluation of these parameters involved three different blowing ratios, M and two value of the turbulence intensities, Tu. The diameter of the cooling holes in the present study is 4.75mm which taken based on the previous study. The present study has been divided into two major studies namely experimental study and simulation study. The purpose of the experimental study is to validate the present simulation study which making use of an open end wind tunnel. As the validation process shows a good agreement results, 14 more models have been built and tested using simulation study which the total cases considered are 105. As for the result, all the considered cases of DCH shows improvement in comparison with SCH. Each of the considered geometries and flow parameters have their own effects on the film cooling effectiveness which will be elaborate in details in the further chapter. As conclusion, the simulation is having good agreement with the present experimental study and the previous study which is essential to confirm the reliability of the study. Meanwhile, all DCH shows improvement in term of film cooling effectiveness on each of blowing ratio value

Machining performance of vegetable oil with phosphonium- and ammonium-based ionic liquids via MQL technique

Thermo-mechanical loads are the main factor that influences the tool wear and product surfaces during machining processes. Lubrication in metal cutting is an effective medium to reduce frictional forces and wear on the tool-workpiece interfaces. On this regards, the advantages of using refined bio-based metalworking fluids (MWFs) with the presence of low toxic, biocompatible and oil-miscible ionic liquids (ILs) additives ([N1,8,8,8][NTf2] (AIL) & [P6,6,6,14][(iC8)2PO2] (PIL)) at nominal weight concentrations of 1, 5 and 10% are explored during orthogonal cutting of AISI 1045 steel. Accordingly, the lubricants are supplied via minimum quantity lubrication (MQL) technique and comparative studies are conducted against the performance of the neat modified Jatropha-based lubricant (MJO) and commercially available synthetic ester-based MQL cutting fluid (SE). The combination of mist supply of the MJOs during machining have a great impact on cleaner production that eliminates the excessive usage of fluids and supports the utilization of environmentally friendly chemicals. This work extends the application of a minute quantity of fully miscible ILs in polar vegetable-based MWF which proven to provide a significant improvement on the lubrication effect of the MJO. MJOþAIL10% and MJOþPIL1% showed the best cutting performance amongst all lubricant mixtures with reduction of cutting forces and specific cutting energy by 4 to 5%, cutting temperatures by 7 to 10%, friction coefficient by 2 to 3%, tool-chip contact length by 8 to 11%, chip thickness by 22 to 25%, friction angle by 1 to 2% and increased shear angle by 25 to 29% compared to the SE. Besides, the effect of low friction and reduced cutting forces produced lower specific cutting energy that promotes “greener” and more sustainable working environment

Human machine interface design analysis of defect detection prototype by wonderware intouch software

Human Machine Interface (HMI) serves as a bridge for operators to understand the processes that occur on the machine. Without HMI, operators will have difficulty in monitoring and controlling the machine. HMI used in this study using Wonderware InTouch software. The HMI design that is used, displays the home button, as the start screen. There are two options in the home menu, which is the option to login as an identification and classification operator. To start operation and enter the monitoring window, any operator that uses this HMI must login using a username and password. The function of HMI in this research is as a connector between operators with machine. In this paper we have presented the human machine interface design of defect detection prototype by wonderware intouch software. Based on the tested results can be concluded that the designed is successfully

A performance of 2 dimensional ultrasonic vibration assisted milling in cutting force reduction, on aluminium AL6061

This paper were investigate a performance of 2 Dimensional Ultrasonic Vibration assisted Milling (UVAM) toward Aluminium Al 6061. The focus is to find the performance of reduction of cutting force compared to the conventional machining in the industries shop floor. Due to the major effect of cutting force of production in industries, the excessive cutting force problem must be investigated deeply as it will cause shortens tool life and reduces the production rate. A scientific approach has been found in order to reduce the cutting force during machining which is integrating the ultrasonic concept into workpiece. The modelling of vibration cutting ratio has been simulated to find the time force contact and non-contact. Thus, less cutting force could be found. The ultrasonic vibration platform that generated by XY25XS from Cedrat Technologies is travelled in X direction as a feed movement. Thus, the X and Y axis vibration actuate along the workpiece for the machining process. The performance of UVAM in cutting force reduction found the superior benefits of UVAM is come from the alternating cycle’s between tool and workpiece. The comparison between UVAM and conventional machining in reduction of cutting force is 32%. The potential of the UVAM tool wear and tool life will be discussed deeply in finding and next in the conclusion section

Investigation on the Tribological Behaviour of Modified Jatropha Oil with Hexagonal Boron Nitride Particles as a Metalworking Fluid for Machining Process

Bio-based oil from vegetable oils was recently explored as an alternative solution to petroleum-based oil. However, the application of vegetable oils as metalworking fluids (MWFs) for machining process is still not widespread. The objective of this study was to investigate the tribological behaviour of modified vegetable oils, in comparison with synthetic ester (SE) and crude jatropha oil (CJO). In this study, the CJO was chemically modified via transesterification process to develop modified jatropha oil (MJO5). MJO5 was then blended with the hexagonal boron nitride (hBN) particles at various concentrations ranging between 0.05 to 0.5wt.%. The friction and wear test was performed using four ball tribotester. An experiment on orthogonal cutting process was carried out to evaluate the machining performances in terms of cutting force, cutting temperature, chip thickness and tool-chip contact length. The results reveal that the mixture of 0.05wt.% of hBN particles in the MJO5-based oil (MJO5a) outperformed the SE in terms of friction and wear. MJO5a showed excellent machining performances by reducing the machining force and temperature, which related to the formation of thinner chips and small tool-chip contact length. MJO5a is the best substitute to SE as sustainable MWFs in the machining operation with regards to the environmental and health concern

Tribological performance of modified jatropha oil containing oil-miscible ionic liquid, for machining applications

Modifying physicochemical and tribological properties of a bio-based lubricant is essential in improving its lubrication performances. This paper presents the effectiveness of a fully oil-miscible Ionic liquid (IL) as lubricant additive into a bio-based lubricant. Methyltrioctylammonium bis(trifluoromethylsulfonyl)imide (AIL) was selected as IL additive to improve the tribological performance of the bio- based lubricant. Additive was mixed into the bio-based lubricant at three levels of mass concentrations (1 wt.%, 5 wt.% & 10 wt.%). Tribology tests on steel/steel contacts were conducted to evaluate the lubricant samples. Test outputs were benchmarked against the neat bio-based lubricant. Results revealed good synergistic effect of the AIL additive blended into the bio-based lubricant. MJO+AIL10 % has shown good corrosion inhibition, superior friction reduction (48 %), lower worn surface area (23 %), excellent surface finish (46 %) and increased tapping torque efficiency (8 %). MJO+AIL10 % provided excellent tribological performances which corresponds to the energy saving and environmental benefit for sustainable machining applications

Three dimensional finite element modeling, when drilling of Ti-6Al-4V

Finite element modeling (FEM) is widely used to optimize machining processes, to predict and analyze the cutting force, cutting temperature and other related responses. Most of the FEM studies were conducted under the two dimensional orthogonal cutting. Drilling process, which involves oblique cutting is not suitable for orthogonal cutting modelling. Therefore, an attempt to simulate a three dimensional simulation of the drilling process is required. A commercially available software called DEFORM is used to accomplish the task. The value of thrust force from the simulation is compared with the experimental results and they are both in a good agreement. Comparison of the drill temperature at TC1 and TC2 are within an error margin of 12%