 | Shaping of Horizontal and Plane Surfaces - Course: Techniques for Machining of Material. Instruction Examples for Practical Vocational Training |
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Introduction
This material contains 4 selected instruction examples for practising and consolidating the knowledge and skills of shaping horizontal and plane surfaces. In order to make preparation and work easier, the necessary materials, tools, measuring and testing means and auxiliaries are given for each instruction example.
As far as the material specification is concerned (instruction examples 2 and 3), the steel is characterized by the value of the tensile strength in the unit "Megapascal" (MPa). Furthermore, the previous knowledge necessary in addition to the knowledge of shaping horizontal and plane surfaces is mentioned. It is recommended to repeat this previous knowledge before starting with the work.
The sequence of operations given for each instruction example includes the order of steps leading to the manufacture of the corresponding workpiece. In order to reach a good quality, it is necessary to follow this order of steps, Each instruction example is provided with a working drawing from which the required shapes and dimensions of the workpiece shall be taken.
The individual instruction examples are given with an increasing level of difficulty. It is also possible to choose other workpieces with smaller or larger dimensions. The admissible deviations for sizes without tolerance indication can be taken from the following tables
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Nominal size |
Admissible deviation |
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0.5 - 6 |
± 0.1 |
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6-30 |
± 0.2 |
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30 - 120 |
± 0.3 |
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120 - 315 |
± 0.5 |
The admissible surface roughness Rz is given in µm (0.001 mm).
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