The friction and wear volume loss is the main cause for a failure & energy losses in heavy-duty gearboxes and it can be controlled by using a modified lubricant mixed with nano additives. This study ...investigates the wear and friction behaviour of gear EP oil blended with composite nano additives (Al2O3/SiO2/ZrO2) in combination with Zinc dialkyl dithiophosphate. All trials were conducted under various concentrations of composite nanoparticles, at loads of 60-100 N and sliding velocities of 0.65-1.5 m/s. The experimental study on antiwear and anti-friction properties for the oil was conducted on a pin-on-disc apparatus. The design of experiment was developed using response surface approach to investigate optimum friction coefficient and wear volume loss in lubricant. It is found that blending of nano composite add-ons blended with Zinc dialkyl dithiophosphate in gear EP lubricant significantly diminishes a wear volume loss, friction coefficient by 15.62 % and 20.6 % respectively as compared to a base lubricant. The findings of this investigation and the obtained correlations were converted in to customized visual basis based soft tool as a predictor for future aspects.
Titanium alloy has a high specific resistance, excellent machining performance is non-corrosive, and the capability to withstand greater temperatures while maintaining outstanding mechanical ...properties. This alloy is, therefore, the right choice for aerospace, maritime, biomedical, and industrial applications. But machinability of titanium alloy is challenging as a result of its poor thermal conductivity, highly chemically reactive, and low elastic modulus hence it is treated as a difficult-to-cut material. Fast tool wear is observed during the machining of titanium alloy in conventional machining methods. Therefore, unconventional processing methods are used for the treatment of titanium alloy. Electric discharge machining (EDM) is one of these unconventional machining processes which are used for cutting with high precision, having a high degree of machinability, and getting a better surface finish. It is considered the best choice for machining titanium alloy. In the EDM process, different techniques are used to understand the effects of process parameters such as polarity, peak current, electrode type, pulse on time, and gap voltage on material removal rate, tool wear rate, surface roughness, and wear ratio. This paper critically investigates different types of EDM processes, experimental setups used for machining of titanium alloy, the effect of different tool electrodes and dielectric media on machining parameters, machined surface characteristics, and metal removal rate and tool wear rate.
In many industries, hydrodynamic journal bearings support the rotor in rotating machineries like large turbines, generators, compressors, gearboxes, etc. where load acts in both axial as well as ...radial direction. Conical journal bearings are more suitable in such applications where both radial and axial load acts on rotating parts. In conical hydrodynamic journal bearings, wear occurs due to continuous use of rotating parts and frequent start-stop activity. The objective of this work is to analyze the wear influence on conical hydrodynamic journal bearing. To achieve this, both experimental and analytical methods are used in this work. Analytically, Reynold’s equation with spherical coordinate system is solved using Finite Element Analysis (FEA) method. In experimental method, Hydraulic oil of Viscosity Grade ISO VG46 is used in Conical Hydrodynamic Journal Bearing (CHJB) test rig along with 10°, 20° and 30° semi-cone angle bearings. The experimental outcomes are in good compliance with that of analytical. The result shows that unworn bearing performance is better compared to worn bearing. The results will be helpful to anticipate the actual behavior of worn conical hydrodynamic journal bearing wherever it is used like in case of blood flow pump, large turbine, etc.
In the recent development of high-performance gas turbine engine, there is a tendency to design the cooling holes in order to improve the heat transfer and cooling efficiency. Titanium alloy is the ...most preferred material for these blades. It is hard material, and hence, the traditional drilling is not appropriate for “Ti” alloy. This research presents the design and optimization required to manufacture contoured holes on a titanium-based superalloy using hybrid electrochemical machining (ECM) under different operating conditions. The circular holes are developed and are analyzed by ANOVA. The experimental results are further optimized using a Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method. The voltage (
V
), feed rate (
f
1
), and feed rate (
f
2
) were identified as the most influencing factors which are further used for stepped circular hole machining. A design of the experiment is also optimized using the TOPSIS method. The obtained experimental results are verified using a SEM analysis to confirm the uniformity of the machined surfaces and the inverse relationship of the overcut with the increasing values of the voltages and feed rates. Optimal machining conditions for the stepped hole machining were determined for voltage 18 V, feed rate “f
1
” at 0.8 mm/min, and feed rate “f
2
” at 1.35 mm/min.
Graphical Abstract
Friction and wear in dynamic parts is the primary reason for energy loss in gearbox lubrication system and this can be optimized by utilizing modified lubricant. The tribological nature of gearbox ...system is critically affected by factors such as type of lubricant, loading & speed etc. In latest years, multiple advanced oil and modern tribological techniques & instruments have been utilized to investigate behaviour of oil like pin on disc, Fourball tester etc. This paper presents comparative investigation of oil blended with additive for two different conditions using prediction model & RSM. The design of experimentations has been conducted by using response surface methodology. The value of inputs parameters such as concentration, load & sliding velocity ranges from 0.5 to 5 %, 60 to 100 N and 0.65 to 1.5 m/s, respectively are utilized to evaluate the outcomes of coefficient of friction and specific wear rate. At the end results from Prediction equations are compared with experimental literature based outcomes to signify the effect of parameters like blend %, load & Sliding speed. The Coefficient of friction model showed 47.57 % more closer outcomes as compared to the Specific wear rate model for specific variation of unknown parameters for pin on disc setup in oil.
The machined surface quality and dimensional accuracy obtained during hard turning is prominently gets affected due to tool wear and cutting tool vibrations. With this view, the results of tool wear ...progression on surface quality and acceleration amplitude is presented while machining AISI 52100 hard steel. Central Composite Rotatable Design (CCRD) is employed to develop experimental plan. The results reported that vibration signals sensed in a tangential direction (Vz) are most sensitive and found higher than the vibrations in the feed direction (Vx) and depth of cut direction (Vy). The acceleration signals in all three directions are observed to increase with the advancement of tool wear and good surface finish is observed as tool wear progresses up-to 0.136mm. The vibration amplitude is discovered high in the range 3 kHz – 10 kHz within selected cutting parameter range (cutting speed 60-180mm/min, feed 0.1-0.5mm/rev, depth of cut 0.1-0.5mm). The investigation is extended for the development of multiple regression models with regression coefficients value 0.9. These models found statically significant and give dependable estimates between a tool vibrations and cutting parameters.
In this paper, the effect of welding parameters of rotary friction welding between AA6063 and AISI4130 and AA6063 and Copper are investigated. The major influencing parameters considered are upset ...pressure, friction time and friction pressure of friction welding are considered for this study. The Taguchi’s design of experiments was conducted for the influencing parameters and their levels. The tensile test experimentation was carried out and the results of the AA6063 and AISI4130 and AA6063 and Copper are compared. The ultimate tensile strength of AA6063-AISI4130 joint and AA6063-Copper joint was improved by increasing upset pressure up to 97MPa with FP of 71 MPa and FT of 4 sec. On the side of AA6063, intermetallic compounds have formed, as seen in SEM micrographs. Microcracks are forming on the side of AA6063 and propagates along the grain boundaries. The effect of the influencing parameters on the tensile strength of the dissimilar joints are studied using the Taguchi’s DOE and ANOVA. From the outcomes it is observed that the friction pressure influence more on the strength of the AA6063 dissimilar joints.
The Containment Filtered Venting System (CFVS) is used to scrub the Particle matter & gaseous pollutants that are liberated during the severe accidents in nuclear power plants (NPP). This research ...work aims to an experimental study of the fluid dynamics of gas-liquid interaction of the circular cross-sectional self- priming VS at different experimental inputs. The performance of self-priming VS is indicated by the Pressure drop, Liquid to gas ratio & Collection efficiency. The effect of Scrubbing liquid height on these performance indicators is studied at different gas flow rates. The experimental result shows that the scrubbing liquid height greatly influences the performance of self-priming VS. It improves the Liquid to Gas ratio which is helpful to improve the collection efficiency.
In this paper, the effect of welding parameters of rotary friction welding between AA6063 and AISI4130 and AA6063 and Copper are investigated. The major influencing parameters considered are upset ...pressure, friction time and friction pressure of friction welding are considered for this study. The Taguchi s design of experiments was conducted for the influencing parameters and their levels. The tensile test experimentation was carried out and the results of the AA6063 and AISI4130 and AA6063 and Copper are compared. The ultimate tensile strength of AA6063-AISI4130 joint and AA6063-Copper joint was improved by increasing upset pressure up to 97MPa with FP of 71 MPa and FT of 4 sec. On the side of AA6063, intermetallic compounds have formed, as seen in SEM micrographs. Microcracks are forming on the side of AA6063 and propagates along the grain boundaries. The effect of the influencing parameters on the tensile strength of the dissimilar joints are studied using the Taguchi s DOE and ANOVA. From the outcomes it is observed that the friction pressure influence more on the strength of the AA6063 dissimilar joints
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