scholarly journals Optimization and Rejection Analysis of IC Engine Rocker Arm

Author(s):  
Chetan Jadhav

Abstract: Today, many technical products need high-precision cylindrical bores which are used, e.g. as a fit or as guidance elements for pistons and shafts. They often need geometric and form accuracy with tolerances less than 1 μm, surface qualities with a roughness less than 1 μm and a high wear resistance. To reach higher production accuracy and better process stability in shorter cycle times, new approaches for the regulation of an automated honing process have to be developed. Due to the great demands regarding the surface roughness which has a great influence on the service life and reliability of parts and the researches of the technical and economical performances of finishing processes were made to optimize the process parameters and constructive parameters of the abrasive tools Keywords: Surface roughness, Analysis, Honing, process parameter, Rocker arm

2018 ◽  
Vol 2 (4) ◽  
pp. 82 ◽  
Author(s):  
Adrián Rodríguez ◽  
Asier Fernández ◽  
Luís López de Lacalle ◽  
Leonardo Sastoque Pinilla

Many manufacturing sectors require high surface finishing. After machining operations such as milling or drilling, undesirable burrs or insufficient edge finishing may be generated. For decades, many finishing processes have been on a handmade basis; this fact is accentuated when dealing with complex geometries especially for high value-added parts. In recent years, there has been a tendency towards trying to automate these kinds of processes as far as possible, with repeatability and time/money savings being the main purposes. Based on this idea, the aim of this work was to check new tools and strategies for finishing aeronautical parts, especially critical engine parts made from Inconel 718, a very ductile nickel alloy. Automating the edge finishing of chamfered holes is a complicated but very important goal. In this paper, flexible abrasive tools were used for this purpose. A complete study of different abrasive possibilities was carried out, mainly focusing on roughness analysis and the final edge results obtained.


Author(s):  
Adrián Rodríguez ◽  
Asier Fernández ◽  
Luís Norberto López de la Calle ◽  
Leonardo Sastoque Pinilla

Many manufacturing sectors require high surface finishing. After machining operations such as milling or drilling, undesirable burrs or insufficient edge finishing may be generated. For decades, many finishing processes have been handmade-basis; this fact is accentuated when dealing with complex geometries especially for high value-added parts. In recent years, it’s a tendency of trying to automate as far as possible this kind of processes, repeatability and time/money savings are main purposes. Based on that idea, the aim of this work is to check new tools and strategies for finishing aeronautical parts, especially critical engine parts made on Inconel 718, a very ductile nickel alloy. Automating edge finishing of chamfered holes is a complicated but really important goal. In this paper, flexible abrasive tools were used for this purpose. A complete study of different abrasive possibilities was carried out, mainly focusing on roughness analysis and final edge results obtained.


2013 ◽  
Vol 773-774 ◽  
pp. 377-391 ◽  
Author(s):  
Eva M. Rubio ◽  
María Villeta ◽  
Beatriz de Agustina ◽  
Diego Carou

This paper presents an experimental study to analyze the surface roughness reached in pieces of UNS M11917 magnesium alloy obtained by intermittent turning. A design of experiments (DOE) was established to carry out the study. Namely, factors identified as posible sources of variation of the surface roughness and their levels, written between parentheses, are the following: depth of cut (1), feed rate (2), spindle speed (2), type of tool (2), quantity of lubrication (3), type of interruption (3), measurement length (3) and measurement generatrice (3). Due to the high number of possible combinations that can be generated with the set of factors and levels identified a combined design of experiments L4x32 was performed. Data are was analyzed by means of the analysis of variance (ANOVA) method. The main results of the statistical analysis highlight the great influence of the feed rate on surface roughness among the set of factors and their interactions considered. In addition, focusing on the intermittent cutting, type of interruption and its interaction with the type of tool used are also important sources of variation, but at a lower level than feed rate.


Author(s):  
Yahya Choopani ◽  
Mohsen Khajehzadeh ◽  
Mohammad Reza Razfar

Total hip arthroplasty (THA) is one of the most well-known orthopedic surgeries in the world which involves the substitution of the natural hip joint by prostheses. In this process, the surface roughness of the femoral head plays a pivotal role in the performance of hip joint implants. In this regard, the nano-finishing of the femoral head of the hip joint implants to achieve a uniform surface roughness with the lowest standard deviation is a major challenge in the conventional and advanced finishing processes. In the present study, the inverse replica fixture technique was used for automatic finishing in the abrasive flow finishing (AFF) process. For this aim, an experimental setup of the AFF process was designed and fabricated. After the tests, experimental data were modeled and optimized to achieve the minimum surface roughness in the ASTM F138 (SS 316L) femoral head of the hip joint through the use of response surface methodology (RSM). The results confirmed uniform surface roughness up to the range of 0.0203 µm with a minimum standard deviation of 0.00224 for the femoral head. Moreover, the spherical shape deviation of the femoral head was achieved in the range of 7 µm. The RSM results showed a 99.71% improvement in the femoral head surface roughness (0.0007) µm under the optimized condition involving the extrusion pressure of 9.10 MPa, the number of finishing cycles of 95, and SiC abrasive mesh number of 1000.


2021 ◽  
Vol 7 (7) ◽  
pp. 67267-67276
Author(s):  
Emillyn Jones Greijal Dias Holanda ◽  
José Guilherme Neves ◽  
Milton Santamaria-Jr ◽  
Silvia Amélia Scudeler Vedovello ◽  
Ana Rosa Costa ◽  
...  

The aim of this study was to evaluate the surface properties of orthodontic resins with and without fluoride. Forty disks, measuring 2 mm thick by 6 mm in diameter, were made of 4 bracket-bonding composite resins (n=10): Transbond Plus Color Change-3M/Unitek (TPCC); Transbond XT- 3M/Unitek (TXT), Orthocem -FGM (OC); Orthocem UV Trace-FGM (OCUV). The discs were photoactivated for 40 seconds with irradiance of 450 mW/cm2 and manually polished in sequence by silicon carbide sandpapers with 1200 and 2000 grain size and finished with diamond paste and felt disc. The surface microhardness analysis was performed using a Shimadzu Micro Hardness Tester HMV-2,000 (Shimadzu Corporation, Kyoto, Japan) with a load of 50 gF and a 5 second penetration time. Surface roughness readings were taken using a Surf Corder Roughness Meter (SE 1700- Kosaka, Lisboa-Portugal). For data analysis, ANOVA (one-way) was used, followed by Tukey's post-test (?=0.05). The microhardness results showed a difference (p?0.05) in the means of the orthodontic resins between TPCC and TXT with the other groups. After the surface roughness analysis, the averages showed that TPCC resin showed higher roughness compared to OC and OCUV (p?0.05), and there was no statistical difference with TXT. It was concluded that statistically the composite resins with fluoride showed significant difference regarding hardness and roughness.


2008 ◽  
Vol 130 (2) ◽  
Author(s):  
M. A. S. Mohamed

Addressed is the mechanism of finishing processes for a workpiece surface using hard abrasive tools such as grinding, abrasive paper, and filing. The mechanism is intended to monitor the gradual changes of the workpiece surface state roughness as the tool is applied for several strokes. Based on a number of common features, the present study simulates each rubbing stroke as a Markov process, and each set of several strokes as a Markov chain. In the simulating model, the discrete probabilistic properties of a specific tool abrasive surface can be expressed in terms of a corresponding Markov matrix operator. Thus, the tool action after one rubbing stroke is obtained via a matrix mapping from a given state roughness to a subsequent state roughness of the workpiece surface. Although the suggested model is capable to handle a comprehensive finishing mechanism, the study focuses on the simple case of zero feeding using a hard abrasive tool, in which the Markov matrix shrinks to a special triangular form. Main findings show that major aspects of the tool surface are transferred to the stepwise roughness state of the workpiece immediately after the first stroke. In addition, regardless of the initial roughness state of the workpiece surface, whether with flat or randomly distributed heights, the ultimate state roughness is unique and definitely features the theoretical case of a plain flat surface. However, this theoretical case is infeasible since it can only be reached after infinite number of strokes.


1989 ◽  
Vol 111 (1) ◽  
pp. 71-73 ◽  
Author(s):  
M. O. Lai ◽  
A. Y. C. Nee

This investigation examines the effects of different finishing processes on the fatigue life of premachined holes in Assab 760 steel plates. The finishing processes studied were reaming, ballizing, and emery polishing. A general decrease in fatigue life with increase in surface roughness is observed for all the processes employed. In comparing the different processes, for a constant surface roughness, polishing is generally found to give the longest fatigue life while ballizing, in spite of the greater compressive residual stresses induced on the surface of the finished hole, the shortest. The surprising phenomenon was found to be attributed to the amount of plastic deformation occurred before fatigue loading. For Assab 760 steel, a prestrain in the radial direction of less than about 2.5 percent appeared to reduce the fatigue resistance of the material.


2016 ◽  
Vol 1136 ◽  
pp. 42-47 ◽  
Author(s):  
Ya Xiong Chen ◽  
Yun Huang ◽  
Gui Jian Xiao ◽  
Gui Lin Chen ◽  
Zhi Wu Liu ◽  
...  

In abrasive belt grinding, abrasive belt granularity, abrasive belt speed,feeding speed and grinding force have a great influence on the surface roughness. In order to predicate the surface roughness of Ti-6Al-4V,a response surface methodology are used to build the model to predict surface roughness,and the influence of various parameters on surface roughness was analysed. The research shows that with the abrasive belt granularity and abrasive belt speed increasing,the work piece surface roughness decreases;with the grinding force and feeding speed increasing,the work piece surface roughness increases. Through the test,the response surface methodology with high prediction accuracy,provides a theoretical basis for the reasonable selection of abrasive belt grinding parameters.


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