Search Results

Mechanical drawing plays an important role in managing, designing and implementing engineering projects, especially in the field of the automotive industry. The need for accuracy in element design and manufacturing is greater now than ever before in engineering industries. In order to increase accuracy, the part design and function must be clearly communicated between the design engineer and the manufacturing technicians, especially in automotive industry and feeder industries projects. Geometric Dimensions and Tolerances (GD&T) system of elements determines the quality, importance and price of the designed product. The standard used in the United States to define GD&T methodology is ASME Y14.5-2009 while the standard used in Europe is ISO 1101-2017. This article discussed the importance of using GD&T system including the types of geometrical features, limitations and accuracy, datum references frame and feature control frame to handle these symbols seamlessly.

Nowadays, research progress in smart material technology plays an important role in precision engineering industries to improve the quality of life. The development of natural materials using new treatment methods and accurate characterization technology in micr- and nano-scale have revealed thin layers from wood or carbon, such as Wood Carbon Sponge (WCS) along with discovery Carbon Nano Tubes (CNTs). Therefore, it became clear that there is a big challenge to prove the strength and durability of WCS and CNTs as smart materials to reach innovative use. This paper summarizes the possibility of using advanced engineering and surface technologies to make the most of the natural and acquired potential of smart functional materials. Laboratory experiments have demonstrated that the smart thin layers materials add new features such as elasticity strength retention that can be useful in developing engineering metrology systems to improve their precision.

Recurrently, the increase in production of high-speed trains worldwide has become a confirmed fact. Seeking to use the high-speed trains locally to link the capital of Egypt “Cairo” with the new industrial cities has become a national requirement. Modeling 3D surface maps using finite element analysis (FEA) is one of the most important mechanical design tools for frictional parts to facilitate the manufacture of brake systems for heavy duty vehicles, especially high-speed trains due to difficult working conditions. In this paper, we presented simulate 3D surface maps for proposed frictional material pad using FEA at certain design parameters and experimental result conductions. The typical surface characteristics of disc brake pad are compared with commonly used materials in railway and vehicle brakes in Egypt.

Optical parameters and hysteresis behaviors play important role as useful diagnostic techniques in quality control for automotive liquids such as brake oils, engine oils and fuels. Refractive index and Brix properties at different concentrations (5 ppm up to 200 ppm) of standard reference chemical liquid solution (Fe(NO3)3) Nonahydrate were determined with an accuracy of ±10-5 using digital multi-wavelengths (refractometer DSR-λ). Practically, the refractive measurements of the selected standard solution have been investigated as a function of temperature (20 οC up to 50 οC) in the spectrum visible range 0.4-0.7 μm. With increasing both wavelengths and temperature the refractive index decreased monotonically. The refractive criteria are also increased with increasing concentration ratio. Moreover, the Brix of the solution have been studied as a function of temperature (20 οC up to 30 οC) with wavelengths in the same visible spectrum range.

There is an eternal extended cooperation between the CMM-coordinate metrology and automotive industry which affecting positively the world economy. Coordinate measuring machine (CMM) is considered as one of the very important techniques to increase the manufacturing quality. Hence, giving more attention to the CMM metrology can play a good role in that area to increase the outcome of the auto industry with high quality. Thus, developing CMM-coordinate metrology techniques constitutes allows important issue and needs more and more scientific research work to enhance the automotive industry. This paper aims to give an overview on the new research works performed in this area during the last few years. The article discusses the latest technology and being updates, such as micro-CMM and hybrid-multi-probe-CMM. On the other hand some new applications of CMM-coordinate metrology techniques in automotive industry have been presented.

The frictional composite is an important material in braking system for automotive, trucks or heavy-duty vehicles. In this paper, a proposed frictional composite material has been developed to achieve the ISO requirements for heavy-duty vehicle brakes. This new frictional material has been fabricated with various compositions. Tribological, chemical, mechanical, thermal conductivity and acoustic noise level tests have measure its performance compared to other two commercial samples under certain operating conditions. Surface characteristics of selected samples have been performed using white light optical microscopy (WLOM) in 2D images to insure the material homogeneity. Additionally, surface roughness analyses using atomic force microscopy (AFM) into 2D and 3D images before and after frictional operation have been investigated.

Straightness uncertainty in dimensional metrology is an important parameter in precision engineering. Optimization in straightness measurement using soft algorithm techniques is widely encountered solution in coordinate metrology. In this work, we report on the uncertainty in the CMM measurement of straightness feature for a slab surface. Straightness points have been measured precisely in 3D using CMM at NIS. The straightness has been analyzed using a Particle Swarm Optimization (PSO) algorithm. The probability density distribution of the measured spatial straightness was developed using a Sequential Monte Carlo (SMC) technique; forming probability density histogram with 95% confidence level representing an uncertainty in the straightness measurement. Comparison with relevant reports showed and approved that our results are more accurate since we used a computationally efficient modified SMC technique and PSO algorithm.

Due to the accidents of the motor vehicles and the osteoporosis, many people enface a lot of troubles and sometimes necessities for replacement of their knee joints. Practically, mechanical properties and surface characteristics of Total Knee Replacement (TKR) are very important parameters for improving the performance response in human. The meniscus is a small element and an essential part of the TKR. The knee meniscus has special feature allows the easy dynamic loading and motion of leg and foot with high accuracy and good balance. Therefore design and analysis of the geometrical shape for the meniscus replacement is worthy to be studied. In this paper, a proposed design using a computer software package has been presented. 3D simulation analyses of a variety of meniscus thickness and different materials under different loads are investigated. The compression stresses and surfaces deformations are determined numerically through the Finite Element Analysis (FEA) technique.

The main aim of this work is to develop an identification method to demonstrate the crucial surfaces of automotive braking system. Two brand new brake discs manufactured by two different manufacturers are tested. A typical disc to the one of them was put under working condition in actual braking system. Dimensional and geometrical deviations are investigated using advanced engineering metrological technique. Mechanical properties, tribological characteristics and chemical analyses are investigated. A coordinate measuring machine, universal hardness tester, mass comparator and XRF spectrometer are used in these diagnoses. Measurements of dimensional and geometrical deviations such as disc thickness variations, thickness deviations, straightness, parallelism, runout of disc surfaces are conducted. A comparison between form deviations in disc surfaces have been carried out and analyzed.

The aim of this research is to assess and develop a polymeric material consisting of a mixture of high-density polyethylene (HDPE) and ultra- high- molecular- weight polyethylene (UHMWPE) reinforced by carbon-nanotube (CNT) by optimizing the mixing concentration of the three constituents. This optimized mixture is accomplished by using a melt extruder-mixing process. An experimental evaluation for accurate assessment of the developed nanocomposite material characteristics is achieved by using a universal tensile test machine and a plint-tribometer pin-on-disc machine. Moreover, the hardness of the material surface and its surface topography are assessed by a hardness tester machine and SEM technique, respectively. Developed samples for testing are classified into two groups of nanocomposites. The first group is created through mixing two pure polymeric UHMWPE and HDPE with different mass ratios of each.

The influence of the pad contact surface deformation for vehicle brakes on its frictional behavior and friction induced noise is presented in this paper. Friction composite samples of organic binder-type brake pad have been curried out at 17 MPa and 180 °C for heavy-duty applications. However, samples with different surface shapes (solid, drilled and grooved) have been formed and tested tribologically to satisfy suitable friction coefficient at low noise level. A FAST machine was used to find out the accurate friction response at steady frictional moment. Friction acoustic noise has been carried out on the test machine using the sound pressure level meter. Analyses of the obtained results showed that the feature of the pad material surface has a significant influence on the brake frictional stability and noise emission. The results also confirmed that; adding a groove to the brake lining in heavy-duty vehicles gives a better brake performance and hence it is highly recommended.