scholarly journals Influence of the frequency of pulsating high-pressure cutting fluid jets on the resulting chip length and surface finish

2021 ◽  
Author(s):  
Antonia Splettstoesser ◽  
Daniel Schraknepper ◽  
Thomas Bergs
Keyword(s):  
High Pressure ◽  
Cutting Speed ◽  
Surface Damage ◽  
Low Pressure ◽  
Cutting Fluid ◽  
Depth Of Cut ◽  
Time Intervals ◽  
Pressure Stage ◽  
Chip Breaking ◽  
Fluid Supply

AbstractHigh-pressure cutting fluid supply is a proven technology for chip breaking when turning difficult-to-cut materials, such as Inconel 718. However, the technology is usually not suitable for the finish turning of safety-critical parts in aero engines. The acting force of the cutting fluid jet on the back of the chip causes chip breaking. The broken chips are then accelerated by the cutting fluid jet towards the workpiece surfaces where they cause damage on impact. One approach to minimize surface damage is a specific increase in the chip length. The center of gravity of the chips with an adjusted length is shifted out of the focus where the cutting fluid jet hits the chips. Hence, the already finished surface is subjected to fewer impacts of the chips. In this study, the adjustment of the chip length by pulsating high-pressure cutting fluid supply to prevent surface damage was investigated. A valve unit was used to generate two alternating cutting fluid supply pressure levels in certain time intervals. During the low-pressure stage, the force of the cutting fluid jet does not lead to chip breakage and the chip length increases until the valves switch and the high-pressure stage is released. The focus of this work was the analysis of the relationship between the duration of the low-pressure and high-pressure time intervals and the chip length. Additionally, the influence of the depth of cut, the feed, and the cutting speed on the chip length during pulsating high-pressure cutting fluid supply was investigated. Finally, a case study was carried out to evaluate the effectiveness of the pulsating high-pressure cutting fluid supply technology. Therefore, the shoulder surface of a demonstrator part was finished by face turning. Following, the cylindrical surface was finished with a continuous and pulsating high-pressure cutting fluid supply with varied supply parameters. Microscopic analyses of the surface prove that the pulsating high-pressure cutting fluid supply prevents the surface from being damaged by the impacts of chips.

scholarly journals Turning Titanium Alloy, Grade 5 ELI, With the Implementation of High Pressure Coolant

Materials ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 768 ◽  
Author(s):  
Bogdan Słodki ◽  
Wojciech Zębala ◽  
Grzegorz Struzikiewicz
Keyword(s):  
High Pressure ◽  
Titanium Alloy ◽  
Fluid Pressure ◽  
Production Costs ◽  
Cutting Fluid ◽  
Depth Of Cut ◽  
Chip Breaker ◽  
Chip Breaking ◽  
Small Depth ◽  
Grade 5

In the machining of difficult-to-cut alloys, such as titanium-based alloys, the delivery of a cutting fluid with high pressure can increase machining efficiency and improve process stability through more efficient chip breaking and removing. Proper selection of machining conditions can increase the productivity of the process while minimizing production costs. To present the influence of cutting fluid pressure and chip breaker geometry on the chip breaking process for various chip cross-sections Grade 5 ELI titanium alloy turning tests were carried out using carbide tools, H13A grade, with a -SF chip breaker geometry under the cutting fluid pressure of 70 bar. Measurements of the total cutting force components for different cutting speeds, feeds, and cutting depth in finishing turning were carried out. The analysis of the obtained chips forms and the application area of the chip breaker have been presented. It was proved that for small depth of cut (leading to small chip cross-section) the cutting fluid pressure is the main cause of the chip breakage, since the insert chip breaker does not work. On the other hand, for bigger depths of cut where the chip breaker goes in action, the cutting fluid pressure only supports this process. For medium values of depths of cut the strength of chip is high enough so that the pressure of the cutting fluid cannot cause chip breaking. A chip groove is not filled completely so the chip breaker cannot play its role.

Performance Analysis of Trihexyltetradecylphosphonium Chloride Ionic Fluid under MQL Condition in Hard turning

2020 ◽  
Vol 17 (1) ◽  
pp. 7629-7647
Author(s):  
A. Pandey ◽  
R. Kumar ◽  
A. K. Sahoo ◽  
A. Paul ◽  
A. Panda
Keyword(s):  
Material Removal Rate ◽  
Feed Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Cutting Speed ◽  
Coconut Oil ◽  
Chip Morphology ◽  
Weight Fraction ◽  
Cutting Fluid ◽  
Depth Of Cut

The current research presents an overall performance-based analysis of Trihexyltetradecylphosphonium Chloride [[CH3(CH2)5]P(Cl)(CH2)13CH3] ionic fluid mixed with organic coconut oil (OCO) during turning of hardened D2 steel. The application of cutting fluid on the cutting interface was performed through Minimum Quantity Lubrication (MQL) approach keeping an eye on the detrimental consequences of conventional flood cooling. PVD coated (TiN/TiCN/TiN) cermet tool was employed in the current experimental work. Taguchi’s L9 orthogonal array and TOPSIS are executed to analysis the influences, significance and optimum parameter settings for predefined process parameters. The prime objective of the current work is to analyze the influence of OCO based Trihexyltetradecylphosphonium Chloride ionic fluid on flank wear, surface roughness, material removal rate, and chip morphology. Better quality of finish (Ra = 0.2 to 1.82 µm) was found with 1% weight fraction but it is not sufficient to control the wear growth. Abrasion, chipping, groove wear, and catastrophic tool tip breakage are recognized as foremost tool failure mechanisms. The significance of responses have been studied with the help of probability plots, main effect plots, contour plots, and surface plots and the correlation between the input and output parameters have been analyzed using regression model. Feed rate and depth of cut are equally influenced (48.98%) the surface finish while cutting speed attributed the strongest influence (90.1%). The material removal rate is strongly prejudiced by cutting speed (69.39 %) followed by feed rate (28.94%) whereas chip reduction coefficient is strongly influenced through the depth of cut (63.4%) succeeded by feed (28.8%). TOPSIS significantly optimized the responses with 67.1 % gain in closeness coefficient.

Influence of Hot Streak Temperature Ratio on Low Pressure Stage of a Vaneless Counter-Rotating Turbine

2007 ◽  
Author(s):  
Qingjun Zhao ◽  
Fei Tang ◽  
Huishe Wang ◽  
Jianyi Du ◽  
Xiaolu Zhao ◽  
...  
Keyword(s):  
Shock Wave ◽  
High Pressure ◽  
Secondary Flow ◽  
Low Pressure ◽  
Turbine Rotor ◽  
Temperature Ratio ◽  
High Pressure Turbine ◽  
Pressure Stage ◽  
Low Pressure Turbine ◽  
Hot Streak

In order to explore the influence of hot streak temperature ratio on low pressure stage of a Vaneless Counter-Rotating Turbine, three-dimensional multiblade row unsteady Navier-Stokes simulations have been performed. The predicted results show that hot streaks are not mixed out by the time they reach the exit of the high pressure turbine rotor. The separation of colder and hotter fluids is observed at the inlet of the low pressure turbine rotor. After making interactions with the inner-extending shock wave and outer-extending shock wave in the high pressure turbine rotor, the hotter fluid migrates towards the pressure surface of the low pressure turbine rotor, and the most of colder fluid migrates to the suction surface of the low pressure turbine rotor. The migrating characteristics of the hot streaks are predominated by the secondary flow in the low pressure turbine rotor. The effect of buoyancy on the hotter fluid is very weak in the low pressure turbine rotor. The results also indicate that the secondary flow intensifies in the low pressure turbine rotor when the hot streak temperature ratio is increased. The effects of the hot streak temperature ratio on the relative Mach number and the relative flow angle at the inlet of the low pressure turbine rotor are very remarkable. The isentropic efficiency of the Vaneless Counter-Rotating Turbine decreases as the hot streak temperature ratio is increased.

Tool Life Analysis when Turning Ti-6Al-4V Using Vegetable Oil-Based Cutting Fluid

2017 ◽  
Vol 882 ◽  
pp. 36-40
Author(s):  
Salah Gariani ◽  
Islam Shyha ◽  
Connor Jackson ◽  
Fawad Inam
Keyword(s):  
Tool Wear ◽  
Tool Life ◽  
Vegetable Oil ◽  
Flank Wear ◽  
Cutting Speed ◽  
Fractional Factorial ◽  
Cutting Fluid ◽  
Depth Of Cut ◽  
Tool Flank Wear ◽  
Fluid Concentration

This paper details experimental results when turning Ti-6Al-4V using water-miscible vegetable oil-based cutting fluid. The effects of coolant concentration and working conditions on tool flank wear and tool life were evaluated. L27 fractional factorial Taguchi array was employed. Tool wear (VBB) ranged between 28.8 and 110 µm. The study concluded that a combination of VOs based cutting fluid concentration (10%), low cutting speed (58 m/min), feed rate (0.1mm/rev) and depth of cut (0.75mm) is necessary to minimise VBB. Additionally, it is noted that tool wear was significantly affected by cutting speeds. ANOVA results showed that the cutting fluid concentration is statistically insignificant on tool flank wear. A notable increase in tool life (TL) was recorded when a lower cutting speed was used.

scholarly journals Nanofluid-based Minimum Quantity Lubrication (MQL) Face Milling of Inconel 625

2019 ◽  
Vol 16 (3) ◽  
pp. 6874-6888
Author(s):  
P. Singh ◽  
J. S. Dureja ◽  
H. Singh ◽  
M. S. Bhatti
Keyword(s):  
Negative Impact ◽  
Cutting Speed ◽  
Minimum Quantity Lubrication ◽  
Face Milling ◽  
Cutting Fluid ◽  
Inconel 625 ◽  
Depth Of Cut ◽  
Base Oil ◽  
Minimum Quantity ◽  
Milling Parameters

Machining with minimum quantity lubrication (MQL) has gained widespread attention to boost machining performance of difficult to machine materials such as Ni-Cr alloys, especially to reduce the negative impact of conventional flooded machining on environment and machine operator health. The present study is aimed to evaluate MQL face milling performance of Inconel 625 using nano cutting fluid based on vegetable oil mixed with multi-walled carbon nanotubes (MWCNT). Experiments were designed with 2-level factorial design methodology. ANOVA test and desirability optimisation method were employed to arrive at optimised milling parameters to achieve minimum tool wear and machined surface quality. Experiments were performed under nanoparticles based minimum quantity lubrication (NMQL) conditions using different weight concentrations of MWCNT in base oil: 0.50, 0.75, 1, 1.25 and 1.5 wt. %; and pure MQL environment (without nanoparticles). The optimal MQL milling parameters found are cutting speed: 47 m/min, table feed rate: 0.05 mm/tooth and depth of cut: 0.20 mm. The results revealed improvement in the surface finish (Ra) by 17.33% and reduction in tool flank wear (VB) by 11.48 % under NMQL face milling of Inconel 625 with 1% weight concentration of MWCNT in base oil compared to pure MQL machining conditions.

Improvement in the performance with less stiff air layer formation around the rubber tube-pasted grinding wheel

2019 ◽  
Vol 233 (15) ◽  
pp. 5175-5189 ◽  
Author(s):  
Spandan Guha ◽  
Partha Protim Das ◽  
Shankar Chakraborty
Keyword(s):  
Cutting Speed ◽  
Cutting Fluid ◽  
Depth Of Cut ◽  
Grinding Wheel ◽  
Rubber Tube ◽  
Layer Formation ◽  
Relational Analysis ◽  
Grinding Performance ◽  
Roughness Amplitude ◽  
Grey Relational

In the grinding operation, a stiff layer of air gets formed around the periphery of the grinding wheel that causes deterioration of its performance. In the present work, in order to restrict the generation of stiff air layer around the periphery of the grinding wheel, a rubber tube is pasted on its surface to improve the grinding performance. An experimental investigation is carried out with low alloy steel as the work material. Taguchi's L9 orthogonal array is considered for the design of experiments while taking cutting speed, depth of cut, and type of the cutting fluid as the input grinding parameters. A comparative analysis using rubber tube-pasted grinding wheel and normal grinding wheel reveals that the developed wheel significantly improves the grinding performance with respect to surface roughness, amplitude of vibration and grinding ratio, as compared to the normal wheel. Moreover, grey relational analysis aided with fuzzy logic is applied in the experimental results to derive the optimal combination of process parameters for further enhancement of the grinding performance. Finally, analysis of variance results identify cutting speed as the most significant parameter while grinding with normal wheel, whereas depth of cut appears to be the most important parameter while machining with rubber tube-pasted grinding wheel.

Experimental Investigation on Turning of Monel K500 Alloy Using Nano Graphene Cutting Fluid Under Minimum Quantity Lubrication

2019 ◽  
Author(s):  
Arul Kulandaivel ◽  
Senthil Kumar Santhanam
Keyword(s):  
Cutting Speed ◽  
Minimum Quantity Lubrication ◽  
High Strength ◽  
High Heat ◽  
Water Soluble ◽  
Cutting Fluid ◽  
Depth Of Cut ◽  
Machining Processes ◽  
Turning Operation ◽  
Minimum Quantity

Abstract Turning operation is one of the most commonly used machining processes. However, turning of high strength materials involves high heat generation which, in turn, results in undesirable characteristics such as increased tool wear, irregular chip formation, minor variations in physical properties etc. In order to overcome these, synthetic coolants are used and supplied in excess quantities (flood type). The handling and disposal of excess coolants are tedious and relatively expensive. In this proposed work, Water Soluble Cutting Oil suspended with nanoparticles (Graphene) is used in comparatively less quantities using Minimum quantity lubrication (MQL) method to improve the quality of machining. The testing was done on Turning operation of Monel K500 considering the various parameters such as the cutting speed, feed and depth of cut for obtaining a surface roughness of 0.462μm and cutting tool temperature of 55°C for MQL-GO (Graphene oxide) process.

scholarly journals OPTIMUM PERFORMANCE OF GREEN MACHINING ON THIN WALLED TI6AL4V USING RSM AND ANN IN TERMS OF CUTTING FORCE AND SURFACE ROUGHNESS

2019 ◽  
Vol 81 (6) ◽  
Author(s):  
Muhammad Yanis ◽  
Amrifan Saladin Mohruni ◽  
Safian Sharif ◽  
Irsyadi Yani
Keyword(s):  
Surface Roughness ◽  
Cutting Force ◽  
Cutting Speed ◽  
Weight Ratio ◽  
Cutting Fluid ◽  
Depth Of Cut ◽  
Ann Model ◽  
Green Machining ◽  
Radial Depth ◽  
Thin Walled

Thin walled titanium alloys are mostly applied in the aerospace industry owing to their favorable characteristic such as high strength-to-weight ratio. Besides vibration, the friction at the cutting zone in milling of thin-walled Ti6Al4V will create inconsistencies in the cutting force and increase the surface roughness. Previous researchers reported the use of vegetable oils in machining metal as an effort towards green machining in reducing the undesirable cutting friction. Machining experiments were conducted under Minimum Quantity Lubrication (MQL) using coconut oil as cutting fluid, which has better oxidative stability than other vegetable oil. Uncoated carbide tools were used in this milling experiment. The influence of cutting speed, feed and depth of cut on cutting force and surface roughness were modeled using response surface methodology (RSM) and artificial neural network (ANN). Experimental machining results indicated that ANN model prediction was more accurate compared to the RSM model. The maximum cutting force and surface roughness values recorded are 14.89 N, and 0.161 µm under machining conditions of 125 m/min cutting speed, 0.04 mm/tooth feed, 0.25 mm radial depth of cut (DOC) and 5 mm axial DOC. 

Technological Investigation of Effect of Machining Parameter on Tool Life

2020 ◽  
Vol 22 (4) ◽  
pp. 41-53
Author(s):  
Manojkumar Sheladiya ◽  
◽  
Shailee Acharya ◽  
Ghanshyam Acharya ◽  
◽  
...  
Keyword(s):  
Surface Roughness ◽  
Mild Steel ◽  
Tool Life ◽  
Flank Wear ◽  
Cutting Speed ◽  
Numerical Control ◽  
Cutting Fluid ◽  
Depth Of Cut ◽  
Machining Time ◽  
Machining Parameter

Introduction. The machinability is typical criteria to be investigated and different authors suggested different parameters describing its quantification. Different parameters i. e. speed, feed, depth of cut, tool work-piece combination, machine types and its condition, cutting fluid, machinist expertise, etc. are contributing directly to the tool life. The selection of the tool for the machining impacts greatly on the economic viability of the machining in terms of energy usage and tooling costs. The method of investigation. The current research emphasis mainly on tool life investigation when machining the mild steel specimens ISRO 50, BIS 1732:1989 at constant cutting speed i.e. 200 m / min. In the industries the mild steel material is commonly used for various products manufacturing. Considering the high demands on productivity and surface finish, machining at 200 m / min is the preferred. The computerized numerical control machine (CNC DX-150) is used for the turning. The four corner insert (TNMG 120408) is used for different machining times i.e. 10, 15, 20 and 25 minutes respectively. The flank wear of the tool is measured with calibrated optical microscope. The temperature of the tool corner during machining is continuously measured for possible impact of temperature on bonding properties of the tool insert and impact on red hardness. Results and discussion. The plot of flank wear vs. machining time will give the value of tool life. The other quality output parameter, such as surface roughness, is measured after machining, indicating surface irregularities in root means square value. Efforts have been made to identify the relationship of tool life, machining time, the quantity of metal removed, surface roughness, and tool bit temperature.

A Model for the Estimation of Pressure Ripple in Tandem Gear Pumps

2015 ◽  
Author(s):  
Mattia Battarra ◽  
Emiliano Mucchi ◽  
Giorgio Dalpiaz
Keyword(s):  
High Pressure ◽  
Dynamic Behavior ◽  
Low Pressure ◽  
Variable Pressure ◽  
Geometrical Parameters ◽  
Gear Pump ◽  
Helical Gears ◽  
Pressure Stage ◽  
Outlet Pressure ◽  
Pressure Ripple

The present paper addresses the development of a lumped parameters model used to analyze the dynamic behavior of a so-called tandem gear pump. The pump is composed of two coaxial stages, both with external gears: a high pressure stage with spur gears and a low pressure one with helical gears. In particular, the paper deals with the modelling and the analysis of the phenomena bound to the pressure distribution around the gears, since they have the most important effect in the dynamic behavior of the pump. The pressure variation in the inlet and outlet chambers, the variable pressure in the trapped volume as well as the pressure evolution from the low to the high pressure chamber is estimated based on the Euler’s approach. The model is developed in Matlab environment. Attention is particularly focused on the description of the methodology adopted for modelling the low-pressure stage, constituted by helical gears, and its influence on the calculation of the pump geometrical parameters. The results provided by the numerical model are compared with experimental measurements in terms of outlet pressure ripple and volumetric efficiency under different working conditions. The results of the validation can be considered satisfactory. Predicted pressure ripple is shown and the effects of interconnections between stages are analyzed studying the outlet pressure ripple in the frequency domain as well.

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