What Is Process Planning? - SKengineers

 

WHAT IS PROCESS PLANNING?

Ø  INTRODUCTION TO PROCESS PLANNING –

·        Process planning is a system of a process responsible for the conversion of raw material into finished product by the most economical way within the limits of design specifications.

·        It can be defined as the systematic determination of the processes by which a product is to be manufactured economically and competitively.

·        It is a function within a manufacturing facility that establishes the processes and process parameters to be used to convert the part to the final form.

·        The process planning consists of activities like determining sequence of operations to be performed, selecting the proper machines, specifying tools, jigs and fixtures, specifying the material to be used, giving the details like speed, feed and depth of cut, specifying the inspection stages.

·        The process planning begins when the products designing is completed. But the basic processes such as casting or forging must be planned during the product design stage only.

·        The inputs to the process planning are the drawing or part points.

Ø  FUNCTION OF PROCESS PLANNING –

1.      To determine the basic manufacturing process.

2.      To determine the sequence of operations.

3.      To determine the equipment and tooling required.

4.      To originate the orders for the process revisions if necessary.

Ø  INFORMATION REQUIRED FOR PROCESS PLANNING –

1.      Engineering drawing of the component.

2.      Knowledge of manufacturing processes.

3.      Resources available in the factory.

4.      Knowledge of various tooling and fixtures.

5.      Relative costs of various processes, tooling and raw materials.

6.      Ability to do computations on machining time and cost.

7.      Knowledge to use reference books, such as machinability data handbook.

Ø  PLANNING OF PROCESSES FROM RAW MATERIAL TO FINISHED PRODUCT –

1.      Part print analysis –

·        Process planning takes the input from the design department in the form of drawing and other manufacturing specifications.

·        These inputs are properly studied and the part list is made to determine the number of parts required in the final product.

2.      Make or buy decision –

·        It is not feasible to manufacture all the parts in the final assembly because some parts are cheaply available and some are difficult or require more time.

·        So a decision is to be made as to which parts are to be manufactured and which are to be purchased from outside and the list is given to the purchasing department.

3.      Selection of basic manufacturing process –

·        Once the decision to manufacture the part is made then the next step is to determine, which basic operations like casting, forging etc.

·        The most suitable method from the various methods is selected by comparing the cost and other factors.

4.      Determine the sequence of operation –

·        Once the manufacturing process is selected, then the sequence of operations is to be determined.

5.      Combine the operations –

·        As many operations as possible should be combined to reduce the production cycle. Operations can be combined by simulation and by integration.

·        Simulation involves those combinations where two or more operations are performed at the same time.

·        In integration, several individual operations are combined in succession but not simultaneously in order to save set up times or loading and unloading.

6.      Selection of machine tools and equipment –

·        Depending on the quantity of product, quality, surface finish required, cost of product, type of material etc. the machines and tools are selected.

Ø  Inspection –

·        This step involves determining the stages of inspection, the tools and gauges required for inspection.

·        Some of the inspection tools are required to be designed, issuing orders to design it.

Ø  Miscellaneous functions –

·        It involves other activities like labour requirement, setting time standards and estimating the cost of production.

·        If the production cost is more than the expected cost then certain revisions in the above steps are necessary.

7.      Preparation of operations and route sheet –

·        This sheet contains the steps to be followed during manufacturing.

·        It lists the manufacturing operations in the decided sequence, tools, set up and operation time, along with the machines associated with each operation.

Part print analysis

Make or buy decision

To select basic sequence of operation

To determine the sequence of operation

Combine the operations

Selection of machines tools and equipment

Inspection

Miscellaneous functions

Preparation of operations and route sheet

 

Ø  FACTORS AFFECTING PROCESS PLANNING –

1.      Production methods.

2.      Size and type of raw material.

3.      Process capability.

4.      Quantity to be manufactured.

5.      Delivery dates of the products.

6.      Surface finish and accuracy required.