Development of the process for mechanical machining of the part Low-speed shaft - heading

2.4 Selection and justification of bases

Selection of technological bases and sequence of workpiece surfaces processing is the most important stage of process development.

The correctness of the decisions made at this stage of technological design largely determines the achievement of the required accuracy of the part in the process of its manufacture and the cost-effectiveness of the technological process.

When machining parts, you must strive to machine a single base surface or process a part using a minimum number of bases.

At installation A of multipurpose operation, the surface of circle ø55 mm is taken as the base with stop against the end of ø55 mm.

On the installation B, as a base, we accept the surface ø40 mm with a stop on the end of ø36 mm.

During the grinding operation, the alignment hole ø12 mm and the face surface ø36 mm are taken as the base.

The selected bases have the correct geometric shape, are processed with an accuracy of 6 liters and provide reliable fixation of the part, as well as the requirements presented by the drawing .