Explain the relationship between the process of planning with the agencies / activities

Process Planning 

The objective of the manufacturing process is to transform an idea into a salable product. 

The common methodology used to accomplish this objective is to divide the manufacturing process into several activities, arranged serially. Usually, each activity handles a different stage of the process, each stage representing a unique discipline and training. 

Fig. 2.1 describes the global structure of an industrial enterprises and points to the role of process planning as a part of production planning. This latter represents the general control of manufacturing activities in an enterprise. Where as the general management of company is concerned with long-range planning activities such as personnel policy, marketing, accounting, etc. it delegates the functions of product design and manufacture to special departments which are in charge of functions such as production planning, fabrication technologies, quality control, etc. the role of process planning itself is now explained.

The place of process planning in the manufacturing cycle-

Process planning is an important link in the manufacturing cycle. It defines in detail the process that transforms raw material into a desired form. The form is defined by the product designer, and is expressed in engineering drawing and GTD- Geometric Dimensioning and Tolerances.

  

More precisely, process planning can be defined by a sequences of activities illustrate in Fig. 2.2 although not necessarily in the order shown. They comprise mainly.

• An interpretation of the specifications contained in the definition drawing of a part, including mainly dimensions and tolerances, geometric tolerances, surface roughness, material type, blank size, number of parts in a batch, etc.; 
• A selection of processes and tools which are candidates for processing a part and its features by respecting the constraints imposed in the definition drawing; 
• A determination of production tolerances and setting dimensions which ensure execution of the design tolerances, while choosing production dimensions for reasons of commodity and capability of manufacturing machinery; 
• A selection of starting surfaces and datum surfaces to ensure precise execution of processing operations simultaneously with a selection of holding fixtures and checking of stability of a part by appropriate damping; 
• A sequencing of operations as a function of priorities imposed by accuracy and technological constraints; 
• A grouping of elementary operations on the same machine so that operation time will be reduced, while respecting accuracy requirements; 
• A selection of machines to execute the technological operations taking into account the number of work pieces to be produced; 
• A selection of inspection methods and inspection instruments to guarantee final conformity of component with functional requirements; 
• A determination of processing conditions for every elementary operation which enable the computation of working times and costs in order to carry out an economic evaluation; and 
• Editing of process sheets to be assembled in a comprehensive process planning file which is transferred to the manufacturing department for, execution. 

Relation between Process Planning with other Activities- 

The process of detailed planning may commence after product and the technology of processing has been identified. Process of planning involve several activity which are given below in a figure-