Technological process of sleeve – a series of entries under the technological preparation of the production process of the part of the sleeve class (including sleeve – general process – forging, Sleeve – technological process, introduction) has been continued. This entry is the first part of the example technological process of the sleeve. The selected sleeve design is discussed below.
I often come across the accusation that “old” conventional machine tools are used in the didactic process. The truth is that only this approach allows for proper presentation of foundations, elementary basic knowledge in the field of technology. Today’s machining CNC centers can be compared to higher-order languages. We lose the ability to look into the viscera of the process, not one thing is hidden from us. If you want to become a good technological engineer, you can not fail to learn the basics.
Below is a modified construction drawing of part of the bushing class (figure 1). The previous, partly cited above entries do not lose their value. Changes were needed so that the technological process of the sleeve could be presented in a better, sometimes easier way.
With regard to the previous design, the shape of the sleeve at the collar was modified where the phase was replaced by a radius transition.
The condition of axial runout tolerance (radial runout or runout in the specified direction) with a value of 0.05 is very simple to meet. The three-jaw chuck in this range should ensure a radial run out tolerance of not more than 0.03.
In case the workpiece is to be subjected to thermal improvement, the key information is the desired surface hardness. For surfaces with a hardness of 35 HRC, this is not considered to be a hard surface and generally their treatment is not a serious problem in terms of technology. As a reminder, 45 HRC are considered to be hard materials abroad, and opinions appear that up to 60 HRC. In the case of workpiece with surfaces with hardness over 45 HRC it is recommended to use hsm (High Speed Machining). The course of the technological process of the class parts of the sleeve and the disk with heat treatment can be found in the previous entry: Class parts bushings and discs.
Technologically important is complex tolerance of position and shape tolerance of longitudinal (axial) beating, for which the base surface is marked with the letter A. Finishing the base surface A (the main hole of the sleeve) and the indicated (dependent) external surface are interrelated. The technological process of the sleeve with the use of conventional machines predicts that the finishing of the hole is the penultimate operation (in the case of external keyways, cross holes). Precise machining of the external surfaces of the sleeve is the last technological operation. The reason is also minimizing the appearance of damage to the external surface.
In the next entries, the technological process for serial production with the use of conventional machines will be presented first.