grinding,grinding machines,binding materials, composite materials,furnaces, rubber ,allowance,fits tolerence.

1. TOPICS:
GRINDING MACHINES
GRINDING WHEEL
FURNACES
REFRACTORY MATERIALS
BINDING MATERIALS
RUBBER
ALLOWNCE
TOLERANCES FITS
COMPOSITE MATERIALS

2. objectives
 Grinding machines
 Different types of grinding machines
 grinding wheels
 dressing and truing
 wheel dressers
 types of wheel dressers
furnaces
Types of furnaces and uses
refractory materials
Types,uses,properties of refractory materials
binding materials and types
rubber
allowance
tolerances fits
composite materials

3. A grinding machine, often shortened to grinder, is
any of various power tool or machine tool used
for grinding, which is a type of machining using
an abrasive wheel as the cutting tool. Each grain of
abrasive on the wheel's surface cuts a
small chip from the work piece.
GRINDING MACHINES

4. 1. Rough Grinders
•Floor or bench grinders
•Portable grinders
•Abrasive belt grinders
•Swing Frame grinders
Types of
GRINDING MACHINES

5. 2. Precision Grinders:
•Surface Grinders
•Cylindrical Grinders
•Tool and Cutter Grinders
Types of
GRINDING MACHINES

6. Hand, electric or air operated portable grinder are used over
surfaces of casting which cannot be handle by swing or bench
grinding.
portable
GRINDING MACHINES

7. Bench grinder which usually has two wheels of different grain sizes for
roughing and finishing operations and is secured to a workbench or
floor stand. Its uses include shaping tool bits or various tools that need
to be made or repaired. Bench grinders are manually operated.
A pedestal grinder is a similar or larger version of grinder that
is mounted on a pedestal, which may be bolted to the floor
bench
GRINDING MACHINES

8. bench
GRINDING MACHINES

9. Belt grinding is an abrasive machining
process used on metals and other
materials. It is typically used as a
finishing process in industry. A belt, coated
in abrasive material, is run over the surface
to be processed in order to remove
material or produce the desired finish.
belt
GRINDING MACHINES

10. belt
GRINDING MACHINES

11. Surface grinding is used to produce a smooth
finish on flat surfaces. It is a widely used abrasive
machining process in which a spinning wheel
covered in rough particles (grinding wheel) cuts
chips of metallic or nonmetallic substance from a
work piece, making a face of it flat or smooth.
surface
GRINDING MACHINES

12. Workpiecebase
Grinding
wheel
table
surface
GRINDING MACHINES

13. surface
GRINDING MACHINES

14. The work piece is rotated and fed past the wheel(s) to form a cylinder. It is
used to make precision rods, tubes, bearing races, bushings, and many
other parts.
cylindrical
GRINDING MACHINES

15. A centerless grinder is a type of cylindrical grinder which uses
two rotary wheels to secure the work piece in place.
cylindrical GRINDING MACHINES

16. A tool and cutter grinder is used to sharpen milling
cutters and tool bits along with a host of other cutting
tools
Tool and cutter
GRINDING MACHINES

17. Internal
GRINDING MACHINES
Internal grinding machines are used to grind
internal holes ,cylinders etc.
Centerless internal grinding

18. Grinding wheels
A grinding wheel is a wheel composed of
an abrasive compound and used for
various grinding. These grinding wheels are
formed out of an aluminum disc or solid steel
by way of attaching the particles to the
exterior surface.

19. composition of
wheel
Grinding wheel composed of:
Abrasives
Bonds
Grain size
grades

20. coding of wheel
 1st letter form is used to specify the type of abrasive
 2nd numeric value tells the grit size (strength)
 3rd alphabet specify grade size ( hardness or softness)
 4th number specify structure
 5th alphabet indicates bond and number tells manufacturer’s
identity number.

21. ABRASIVE GRIT SIZE GRADE SIZE STRUCTURE BOND CODE SYMBOL
Course Medium Fine
"D"
to
"H"
Soft
Dense
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Open / Porus
B- Resinoid
Letters or Numbers to Designate a Variation
of bond or characteristics of the wheel
Aluminum Oxide "A" 8 V - Vitrified
White Aluminum Oxide "AA" 10
R - Rubber
E - Shellac
Pink Aluminum Oxide "RA" 12
"I"
to
"P"
Mediu
m
Mixture of Brown "A" 14 O - Oxychlo
Black Silicon "C" 16 S - Silicate
Green Silicon Carbide "G C" 20
"R"
to
"Y"
Hard
Aluminum Zirconium "Z"
24

22. Types of grinding
wheels
Some types of grinding wheels are as under:
 straight grinding wheel
 cylinder or wheel ring
 tapered grinding wheel
 straight cup wheel
 dish cup wheel
 saucer grinding wheel
 diamond grinding wheel

23. Dressing and truing
of
grinding wheel
Dressing means to clean and removes dull and excess
bonding material.
Truing is the cutting of wheel to give it a new shape.
Diamond tool dressers are used for truing.

24. wheel dresser
Wheel dresser is a tool used for dressing or truing a
grinding wheel to give the wheel its original form.

25. Types of wheel dresser
Types of wheel dressers includes:
 Diamond dresser
 Diamo-carbo dresser
 star or Huntington dresser

26. Diamond dresser
Diamond dresser is a short handled tool consists of bonds
of small diamonds.

27. Diamo - carbo dresser
Diamo - carbo dresser is a tube which is filled with hard
abrasive.

28. Star (Huntington) dressers
Huntington dresser is a long handled tool with a row of
star shaped cutter, as its name.

29. What are furnaces?
 The name furnace derives from Greek
Word “FORMAX” which means oven
 A furnace is a device used for high
temperature
heating

30. A furnace is an equipment used to melt the
metals
 For casting
 For heat the different material
 For change shape ( rolling , forging etc)
 For change properties ( heat treatment)
USES OF FURNACES

31. FURNACE

32. COMPONENTS OF
FURNACES
The principle components are
Suitable refractory material
Source of energy
Heat exchanger
 INSTRUMENTATION AND CONTROL

33. SOLOR ENERGY
a) Fossil fuel: For fossil fuel one requires burner for
efficient mixing of fuel and air. Arrangement of
burner is important.
b) Electric energy: Resistance heating, induction
heating or arc heating.
c) Chemical energy: Exothermic reactions

34. SUITABLE REFRACTORY
MATERIAL
Refractory design is important. Thermal enclosure of the furnace
is designed and constructed keeping in view the requirements. For
example refractory facing the thermal enclosure must have high
refractoriness, chemically inert etc. Whereas refractory facing the
surrounding must have low thermal conductivity to minimize heat
losses.

35. HEAT EXCHANGER
Heat exchanger is becoming now as part of the fossil fuel fired
furnaces in order to recover and reuse the heat of POC. Heat of
POC can be used either external to Furnace by installing a heat
exchange or internally by recirculation the POC within the
furnace.

36. INSTRUMENTAATION
AND CONTROL
Furnaces are equipped with POC analyzer
and temperature control.

37. FURNACES AND THEIR
APPLICATION IN HIGH
TEMPERATURE INDUSTRIES
Furnaces are used for wide variety of processing of raw
materials to finished products in several industries.
 Broadly they are used either for physical processing or for
chemical processing of raw materials.
 In the physical processing the state of the reactants remains
unchanged
 whereas in the chemical processing state of the reactants
changes either to liquid of gas.

38. "...non-metallic materials having those chemical and physical
properties that make them applicable for structures, or as
components of systems, that are exposed to environments above
1,000 °F (811 K; 538 °C)."
Refractory materials are used in
furnaces, kilns, incinerators and reactors.
refractory materials:

39. Uses of refractory materials:
• make crucibles and moulds for casting
•for rocket launch structures
•. the iron- and steel-industry
• metal casting sectors use approximately 70% of all refractory produced.

41. types of refractory materials:
REFRACTORY
MATERIALS
SHAPED UNSHAPED
bricks
REFRACTORY
MATERIALS
Mortar,filler ,spray

42. Common refractory materials:
Fire clay brick SiO2 78%
Al2O3 44%
Alumina aluminum oxide and traces of
other materials
Silica brick 93% silica
Magnesite 85% magnesium

43. Binding materials
A binder or binding agent is any material or substance that holds binders are
liquid or dough-like substances that harden by a chemical or physical process
and bind fibers, filler powder and other particles added into it. Examples
include glue, adhesive and thickening.

44. Binding materials
Binders used in
 Painting
 Sculpture
 Construction of buildings concrete
 explosives, wax or polymers
 composite materials, epoxy, polyester

45. Types of Binding materials
BINDERS
ORGANIC
BINDERS
INORGANIC
BINDERS
animal and
plant glues,
polymers
lime, cement, gypsum,
liquid glass,
SYNTHETIC
BINDERS
Clay is used as binder in molding sand for making moulds
grinding wheels are made with five types of bonds; (V)Vitrified,
(B)Resinoid, (MgO) Oxychloride magnesium, (E)Epoxy, (R)Rubber.

46. RUBBER
 Think of rubber and you probably think of elastic bands, car tires, or
pencil erasers. But this super-stretchy material actually finds its way into
tens of thousands of different products
 Rubber, which has been commonly used for over 1000 years, once came
entirely from natural sources
 now rubber products are just as likely to be made artificially in chemical
plants.
 That's largely because we can't produce enough natural rubber to meet
all our needs.
 And that, in turn, is because rubber is so fantastically useful. Let's take a
closer look at one of the world's most amazing materials!

47. TYPES OF RUBBER
There are many different kinds of rubber, but
they all fall into two broad types:
natural rubber (latex—grown from plants) and
 synthetic rubber (made artificially in a
chemical plant or laboratory).

48. NATURAL RUBBER
 Natural rubber is made from a
runny, milky white liquid
called latex
 Although there are something
like 200 plants in the world that
produce latex, over 99 percent of
the world's natural rubber is
made from the latex that comes
from a tree species called Hevea
brasiliensis, widely known as the
rubber tree.

49. USES OF NATURAL
RUBBER

50. SYNTHETIC
RUBBER

51. The largest consumers of rubber are tires and tubes, followed
by general rubber goods.
 Other significant uses of rubber are hoses, belts, matting,
flooring, medical gloves and much more.
 Rubber is also used as adhesives in many products
and industrial applications.
USESOF RUBBER

52. allowance
Allowance is defined as the planned deviation between an
exact dimension and a final or theoretical dimension.
example:
The outer diameter of a pin may be planned to 0.13 mm
because after the heat treatment, it will going to shrink
0.13 mm hence comes to it original size.

53. Allowance
(example)

54. TOLERANCE
A Tolerance is defined as the total permissible
variation of a size
 If you leave a dimension without a tolerance,
no one else will know the importance, or the
unimportance, of that dimension. When used
correctly, you have much to gain when
using tolerances.

55. FITS
The degree of the tightness or looseness between two
mating points is called FITS

56. Composite materials
Composite materials are materials made by
combining of two materials to minimize
defects are increasing characteristic for
different uses.

57. Binding materials

58. Binding materials