Mechanical engineering

1. Explain about conven onal process planning.
Conven onal process planning is a method of crea ng a set of instruc ons for a machine tool to perform a specific
machining opera on on a workpiece. It is based on the manual analysis and selec on of the processes, machines,
tools, and parameters by a skilled and experienced process planner. The process planner has to write the instruc ons
using a standard code language, such as G-code or M-code, and check the syntax and logic of the program manually.
The process planner also has to es mate the me, cost, and quality of the machining process.
Some of the advantages of conven onal process planning are:
 It is simple and low-cost, as it does not require any computer system or so ware.
 It is flexible and adaptable, as it can handle any type of workpiece and machining opera on.
 It is crea ve and intui ve, as it can u lize the knowledge and experience of the process planner.
Some of the disadvantages of conven onal process planning are:
 It is me-consuming and error-prone, as it involves a lot of calcula ons and data processing by the process
planner.
 It is inconsistent and unreliable, as it depends on the skill and judgment of the process planner.
 It is inefficient and wasteful, as it may not op mize the use of the resources and facili es.
Explain about computer aided process planning.
Computer-aided process planning (CAPP) is the use of computer technology to aid in the process planning of a part or
product, in manufacturing. CAPP is the link between CAD and CAM in that it provides for the planning of the process
to be used in producing a designed part. CAPP can help to improve the efficiency, quality, and consistency of the
manufacturing process, as well as reduce the cost and me required for process planning.
There are two main types of CAPP systems: Retrieval type and Genera ve type.
Genera ve type CAPP systems create new and op mal process plans for any part, based on the logical rules and
algorithms of the system. Genera ve type systems are more complex and slower, but more capable and versa le.
Retrieval type CAPP systems store and retrieve standard process plans for similar parts or part families, based on the
geometric and technological features of the parts. Retrieval type CAPP systems are simpler and faster, but less flexible
and adaptable than genera ve type CAPP systems.
Difference between Conven onal process planning and Computer aided process planning
Conven onal process planning and computer-aided process planning are two methods of preparing a detailed set of
plans and instruc ons to produce a part or an assembly. The main differences between them are:
Conven onal Process Planning CAPP
Conven onal process planning is done manually
by human experts
CAPP is done by using a computer system that can
systema cally generate accurate and consistent process plans.
Conven onal process planning relies on the
experience and knowledge of the process planner
CAPP uses a database of technical informa on and logic to
create the process plan.
Conven onal process planning is me-consuming,
error-prone, and difficult to update
Computer-aided process planning is faster, more reliable, and
easier to modify.
Conven onal process planning may result in
different process plans for the same part
depending on the planner,
computer-aided process planning ensures standardiza on and
op miza on of the process plans.

2. Explain two approaches of CAPP? (10M)
There are two types of computer-aided process planning systems: retrieval type and genera ve type.
Retrieval type CAPP systems are computer-aided process planning systems that store standard process plans for
different part families in a database. A part family is a group of parts that have similar manufacturing characteris cs,
such as shape, size, material, and opera ons. When a new part is to be manufactured, the retrieval type CAPP system
retrieves the most suitable process plan from the database and modifies it according to the specific requirements of
the part. Retrieval type CAPP systems are easy to implement and maintain, but they have limited flexibility and
cannot handle complex or novel parts.
Some of the advantages of retrieval type CAPP systems are:
 They can reduce the planning me and cost by reusing exis ng process plans.
 They can improve the consistency and quality of process plans by elimina ng human errors and varia ons.
 They can facilitate the standardiza on and documenta on of process plans by using a common format and
structure.
 They can support the integra on and communica on of process plans with other computer-aided systems,
such as CAD, CAM, and ERP.
Some of the disadvantages of retrieval type CAPP systems are:
 They require a large and reliable database of process plans for different part families, which can be difficult
and expensive to build and update.
 They may not be able to handle complex or novel parts that do not belong to any exis ng part family, or that
require special or customized opera ons.
 They may not be able to op mize the process plans for different criteria, such as cost, quality, me, or
environmental impact.
 They may not be able to adapt to changes in the design, technology, or market condi ons that affect the
manufacturing processes.
Genera ve type CAPP systems are computer-aided process planning systems that create process plans from scratch
based on the geometric and technological data of the part. The genera ve type CAPP system, also called as an exact
system, creates the process plan for a new part automa cally without human interven on. The genera ve type CAPP
system uses logical rules, algorithms, and expert knowledge to generate the op mal sequence of opera ons, machines,
tools, parameters, and other details for the part. Genera ve type CAPP systems are more flexible and capable of
handling complex and novel parts, but they require more development and computa onal resources.
Some of the advantages of genera ve type CAPP systems are:
 They can op mize the process plans for different criteria, such as cost, quality, me, or environmental impact.
 They can adapt to changes in the design, technology, or market condi ons that affect the manufacturing
processes.
 They can handle complex or novel parts that do not belong to any exis ng part family, or that require special
or customized opera ons.
 They can generate process plans for parts that have not been designed yet, by using parametric or feature-
based models.
Some of the disadvantages of genera ve type CAPP systems are:
 They require a large and reliable database of technical informa on and logic for process planning, which can
be difficult and expensive to build and update.

3.  They may not be able to capture the tacit knowledge and experience of human process planners, which may
be useful for some situa ons.
 They may generate process plans that are too complex or imprac cal for the actual manufacturing condi ons,
such as machine availability, tool wear, or operator skill.
 They may require more me and computa onal power to generate the process plans, especially for large or
complicated parts.
Opitz part classifica on and coding.
 It is a mixed (hybrid) coding system
 Developed by Opitz, Technical University of Aachen, 1970
 It is widely used in industry
 It provides a basic framework for understanding the classifica on and coding process
 It can be applied to machined parts, non-machined parts (both formed and cast) and purchased parts
 It considers both design and manufacturing informa on
Prac ce these.
Also prac ce the CNC programs (Lab Experiments).

4. Flexible Manufacturing System (FMS) kuda okasari chusuko enthakaina manchidi.
Ee ques ons exam ki rakapote nannu emi anakandi, okavela vasthe pogadandi, rakapote matram akandi.