2. PROCESS PLANNING
According to the American Society of
Tool and Manufacturing Engineers
“ Process Planning is the systematic
determination of the methods by which
a product is to be manufactured
economically and competitively”
To prepare a set of instructions that
describes how to manufacture the
product and its parts.
To prepare a detailed specification
which lists the operations, tools and
The prepare the functional
requirements of the product, quantity,
tools and equipment, and eventually
the cost for manufacture.
5. PROCESS PLANNING ACTIVITIES
Analyze the Part Requirements
Determine the Operation
Select the necessary
Calculate the Processing time
Document Process Planning
Mfg. engr. Shop
6. ANALYSE FINISHED PART
To analyze the finished part
requirements as specified in the
The engineering design may be
shown as a drawing or CAD model
Based on the feature, dimensions and
tolerance specifications the
requirements are identified.
7. DETERMINE THE OPERATING
To determine the type of processing
operation that has the capability to
generate the various types of features
based on the tolerance.
Two alternative ways of viewing the
(a) As a conventional production shop,
material is removed or modified on the
rough part in stages in order to
convert it to the finished part
9. SELECT MACHINE
Production rate and unit cost of
Durability and dependability
Lower process rejection
Minimum set up times
Longer productive life of machines.
10. MATERIAL SELECTION
Function : Material must perform in
terms of mechanical, physical,
electrical and thermal properties.
Appearance : The aesthetic value of
the material must be considered.
Reliability: Increasing consumer
demands for trouble free products
Service Life : The length of the
service life over which a material
retains its characteristics.
11. MATERIAL SELECTION
Environment : The material should
sustain the environmental conditions
whether it is beneficial or harmful.
Compatibility: When more than one
material is used in a product or
Producibility : Material should be
able to be used for which it is intended
Cost : The cost of the material should
12. CALCULATE PROCESSING
Calculate the set up times and cycle times.
Set up time is calculated based on the
available tooling and sequence of steps.
The processing time based on the
sequence of operations is calculated
Part loading and part unloading time is
Standard cycle time = set up time +
processing time + part loading + Part
unloading + allowances
Standard cost calculated for the given part
14. ROUTE SHEET
Description of the processing steps in
Operation sequence and machines
Standard set up time and cycle times
Production control information
showing the planning, lead time at
15. REASONS FOR
To have a record on how a part is
processed in order to plan future parts
with similar design requirements
To provide a record for future job
quoting, cost estimating and standard
To act as a means for communication
Communicate the manufacturing
knowledge to the shop floor.
To ensure that the route sheet is
To maintain quality in manufacturing.
18. MANUAL PROCESS PLANNING
Examining and interpreting the
Making decisions on machining
Equipment selection, tools etc.
Dependent on the skill and judgment
of the process planner.
Different planners may produce
different process plans.
19. ADVANTAGES & DISADVANTAGES
Used for small scale industries where there
only few processes involved.
Low investment costs
Time consuming involving large amount of
Skilled process planner
Increases paper work
Inconsistent process plans result in lower
Reduces routine clerical work
Generates rational, consistent and
Interfaces CAD and CAM.
22. RETRIEVAL CAPP
Idea behind retrieval CAPP is that
similar parts have similar process
Based on the principle of group
Parts classified and coding.
For each part family a standard
process plan (route sheet) is prepared
and stored in computer.
23. RETRIEVAL CAPP
Code number is generated for each
When needed for a new part the
standard plans are retrieved and
edited for a new part.
24. ADVANTAGES& DISADVANTAGES
Using a standard plan a variety of new
parts can be planned.
Easy to understand and implement.
Experienced process planners are
required to modify the standard plan.
(Multi CAPP, MIPLAN)
The components to be planned are
limited in number
25. GENERATIVE CAPP
Generates the process plans based
on the decision logic and pre coded
The computer stores the rules of
manufacturing and equipment
A Specific process plan for a specific
part can be generated without the
involvement of a process planner.
The human role includes
(a) Input the GT codes for the part
26. COMPONENTS OF A GENERATIVE CAPP
A part description : identifies series of
component characteristics, including
Machining Parameters : To decide the
Select and Sequence
individual operations : Decision logic
and Decision trees, algorithms are
used to calculate the sequence and
27. COMPONENTS OF A
Data base : Available machines and
Report Generator : Prepares the
process plan reports
28. ADVANTAGES &
(1) Consistent process plans
(2) New components can be planned
(3) Automation is easy because it
gives a detailed control information.
(1) Complex and very difficult to
Software's used : CMPP, EXCAP