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The MaxiMOST System
Published in Kjell B. Zandin, Therese M. Schmidt, ® Work Measurement Systems, 2020
Kjell B. Zandin, Therese M. Schmidt
Machine Handling is used for analysis of the manual operations associated with manipulating the controls of machines. As with Part Handling and Tool Use, the Machine Handling Sequence Model accounts for total walking distance and total body motions required for the completion of the use of machine controls. The Machine Handling Sequence Model is used for the analysis of situations such as: Set controls on a machine or equipment.Secure the workpiece for machining.Set feed and/or speed.Activate controls.
Mechanical Non-Traditional Machining Operations and Machine Tools
Published in Helmi Youssef, Hassan El-Hofy, Non-Traditional and Advanced Machining Technologies, 2020
The material removal rate, accuracy, and surface quality are influenced by the workpiece material and the machining parameters. Brittle materials fracture, while ductile ones are cut well. Material thickness ranges from 0.8 mm to 25 mm or more. Table 2.1 illustrates the cutting rates for different material thicknesses. For a given nozzle diameter, the increase of pressure allows more power to be used, which in turn increases the penetration depth or the traverse speed. The quality of cutting improves at higher pressures and lower traverse speeds. Under such conditions, greater thicknesses can be cut.
The influence of additive powder on machinability and surface integrity of SKD61 steel by EDM process
Published in Materials and Manufacturing Processes, 2021
Therefore, the application of the PMEDM method to improve machining properties and surface properties is a promising solution. This is accomplished through a combination of the properties of the powder material, thermal energy of the EDM process, and the substrate material of workpieces, which form chemical and physical processes. The result is desirable properties of workpiece surfaces such as smooth roughness, high hardness of surfaces, few defects, and improved machining performance. Many researchers have investigated the different features of PMEDM. In 1980, Erden et al reported that,[13] the domination of the conductive suspended in the insulating oil solvent of the EDM process, that has enhanced the quality of surfaces, the ability to remove material, and tool wear reduction. Recently, researchers have concentrated on enhancing surface quality, material removal rate (MRR), and tool wear rate (TWR). Some of the studies are mentioned as follows:
Integrating the setup planning with fixture design practice by concurrent consideration of machining and fixture design principles
Published in International Journal of Production Research, 2021
In the proposed integration method, two different cases may occur for a multi-TAD feature. In the first case, one of the tool approach directions is the same as TAD of the setup under consideration (right side in Figure 3). In this case, TAD of the setup is assigned to the multi-TAD feature, and the feature is placed in the setup. This not only leads to minimum number of setups but also allows interrelated features to be accommodated in the same setup. In the second case, a new setup is created based on the multi-TAD feature (left path in Figure 3). In this case, first TADs which have clash with the reference faces (i.e. the locating surfaces of the setup) are excluded. Then, a TAD is selected along which the feature has the largest surface in that direction. This allows maximum stability of the workpiece to be obtained.
A 2D finite element analysis of the effect of numerical parameters on the reliability of Ti6Al4V machining modeling
Published in Machining Science and Technology, 2020
Mariem Yaich, Yessine Ayed, Zoubeir Bouaziz, Guénaël Germain
Several phenomena are involved during the machining process. The workpiece material is subjected to important temperatures, strain rates, dislocations motion, microstructure changes, etc. In addition, significant levels of friction at the contact interfaces, followed by a local increase of the temperature, are reached. Therefore, the adoption of advanced experimental devices with high precision (e.g. high frame rate camera) are required to capture these instantaneous changes, mainly undergone in very thin layers. Despite continuous efforts to well understand the machining process of difficult-to-cut materials, the experimental determination of physical phenomena involved during the chip formation process is still problematic. Therefore, theoretical methods (e.g. analytical, numerical and hybrid models) are generally required, in addition to the experimental tests.