TEPES OF PATTERNS IN CASTING CLASS: BY POLAYYA CHINTADA

1. LENDI INSTITUTE OF ENGINEERING
AND TECHNOLOGY
PRODUCTION TECHNOLOGY
COURSE CODE: C211
REGULATION: R19
2nd BTECH 2nd SEM
PREPARED BY :
POLAYYA CHINTADA M.TECH,M.B.A,(PhD)
ASSISTANT PROFESSOR
TOPIC:
TYPES OF PATTERN AND ITS
APPLICATIONS

2. PRODUCTION TECHNOLOGY
SYLLABUS
UNIT 1:
Introduction: Importance and selection of manufacturing processes.
Casting Processes: Introduction to casting process, process steps; pattern: types, materials and
allowance; Cores: Types of cores, core prints, principles and design of gating system; Solidification
of casting: Concept, solidification of pure metal and alloy; Special casting processes: Shell casting,
investment casting, die casting, centrifugal casting, casting defects and remedies.
provide insight into Working
principles of different metal casting
processes and gating system
COURSE OBJECTIVE: COURSE OUTCOMES:
Explain different metal
casting processes and
gating systems. (L2)
APPLICATIONS:
Identify different patterns
and their allowances (L3)
1. Heavy Equipment : Construction, farming
and mining
2. Defence : Vehicles, artillery, munitions,
storage and supporting equipment
3. Hardware : Plumbing industry pipes,
joints, valves and fitting
Identify the various
casting defects. (L3)

3. PATTERN
 Pattern is a mirror image or replica of the
component that has to be manufactured by
casting process.
 It may be also defined as a model around which
sand is packed to give rise to a cavity called mold
cavity.
 A pattern is required even if one object has to be
cast.
 The materials generally used for pattern are
wood, metal or plastics.

4. TYPES OF PATTERN
 Solid or single piece pattern
 Split pattern or two piece pattern
 Multi piece pattern
 Match plate pattern
 Gated pattern
 Skeleton pattern
 Sweep pattern
 Pattern with lose pieces
 Cope and drag pattern
 Follow board pattern
 Segmental pattern

5. SOLID OR SINGLE PIECE PATTERN
 Simplest pattern
 Made in one piece
 Cheapest pattern
 Soil tamper
 Stuffing box
 Gland of steam engines
 it is used for new, large and simple
castings
APPLICATION:
 Steam Engine
https://www.youtube.com/watch?v=Uv28tqCOtAg

6. TWO PIECE OR SPLIT PATTERN
 Pattern is split into two pieces
 One part is in cope and other is in drag
 Easy withdrawal of pattern
APPLICATIONS:
 Spindles
 Steam valve bodies
 AK-47 rifle stock
 They are made in two parts and these two parts of
the pattern are joined together with the help of dowel pins
https://www.youtube.com/watch?v=hwrTfxMeDns

7. •As the name suggest, loose piece pattern has more than two pieces of the pattern
•Small pieces (sibling pieces) of the pattern is attached to the main piece of pattern
using wire
•When molding is over, the main piece of pattern (large pieces) is removed from the
mold, then loose and withdraw the small pieces through the gap generated by the
main piece.
•This pattern requires more time and labor
LOOSE PIECE PATTERN
https://www.youtube.com/watch?v=DyJiBaEPMtY

8. Multi-piece pattern
 Pattern is split into more than two parts.
 Facilitates an easy moulding and withdrawal of
pattern.
 Pattern may consists 3,4 or more numbers
depending on designs
APPLICATIONS:
 Lap joint
 Dowel joint
 Mitre joint

9. MATCH PLATE PATTERN
 Patterns are made in two pieces one piece
mounted on one side and the other on other side
of plate called match plate.
.
 Along with pattern gates and runners are also
attached.
 Produces accurate castings at faster rates.
APPLICATIONS:
Generally used for small castings such as piston
rings of I.C. engines and rotor hub.
 These are used for mass production these
patterns find a great favor in machine molding.
https://www.youtube.com/watch?v=v-lSW16PFt8
https://www.youtube.com/watch?v=rf8n9J2CDV4
https://www.youtube.com/watch?v=LP5aTTrjwQA

10. Gated pattern
 In this the pattern are usually made of metals.
 In this multi-cavity moulds are produced & the
sections connecting different pattern serves as
gate and runner. This facilitates filling the mold in
better manner.
 Can produce many castings at one time and
hence saves time as well as cost.
APPLICATIONS:
Used for small castings such as corner bracket.
They are used in mass production for such castings
multi
– cavity moulds are prepared
https://www.youtube.com/watch?v=Jk2PC2o_XSg

11. https://www.youtube.com/watch?v=tB2ga9mISks

12. https://www.youtube.com/watch?v=tB2ga9mISks

13. Cope and drag pattern
 In this pattern is made into two halves and both
are molded in different boxes.
 After completion of mold two boxes are
assembled to make a cavity.
 It is also known as two piece or split
pattern.
APPLICATIONS:
 Flange pipe.
 Water Jacket of JCB head.
 Hose pipe coupling head.
https://www.youtube.com/watch?v=m4qBETv7bX0
https://www.youtube.com/watch?v=vQz3GZoi7NQ

14. Follow board pattern
 It is a wooden board used to support during
moulding.
 Acts like a base seat for pattern.
 Follow board are used for those patterns which
has odd shapes.
 It supports weak pattern and also acts like natural
parting line.
APPLICATION:
https://www.youtube.com/watch?v=o-FICSc39sY
https://www.youtube.com/watch?v=tB2ga9mISks
This pattern is used in processes where casting
structures are weak and they may break after
the application of force.

15. Yours:
POLAYYA CHINTADA M.TECH,M.B.A,(PhD)
ASSISTANT PROFESSOR
https://www.slideshare.net/hareeshang/introduction-to-
manufacturing-process