Engineering plastics, Mechanical Engineering

Assignment Help:

Engineering Plastics

In this time this has become clear to know, the plastics are utilized as engineering materials for machine parts, casting and bodies and for structure mainly due to low density though their strength is much less than such of metal. In the electrical engineering field the plastics are utilized caused their excellent insulating properties, normally measured in forms of dielectric strength in V/m. Their low melting point is a weakness or negative advantage and in a lot of applications the maximum employ temperature is a yardstick also. The impact strength of plastics is other important characteristic and in applications, here vibration is likely to arise plastics of low impact strength are not favored. The capability of plastics to be made in thin walled bags so foamed structure, in various colours and to be recycled or thermoplastics are added advantages. Their non-degradability has undoubtedly that provide ascend to problems of last applications and disposal, at this time they can be discarded via users in public places is to discouraging. Table no.1 illustrates a few plastics, their applications and properties.

                                                                                                                       Table no.1

 Sl. No.

Plastic

Density

(g/cm3)

Tensile Strength (MPa)

Iozed Impact Strength (J/m)

Dielectric Strength (V/m)

Maximum Use Temperature (oC)

Applications

1

Polyethylene Low Density High Density

 

0.92-0.93

0.95-0.96

 

6.0-17

20-37

 

-

21-748

 

18912

-

 

82-100

80-120

Corrosion resistant, Containers, Tubing, Houseware and Electrical insulation, Packaging film.

2

Rigid Chlorinated

PVC

1.49-1.58

50-68

53-400

-

110

Chemically resistant, Building material, Auto upholstery, Shoes, Suitcases, Refrigerator gasket, Electrical wire insulation.

3

Polypropylene

0.90-0.91

33-38

21-117

25610

107-150

Bottles, Laboratory ware, Packaging, Fan shrouds, Heater ducts, Battery housing in automobiles.

4

Styrene Acrylonitrile (SAN)

1.08

70-83

21-27

69935

60-104

Instrument lens and dash board components in automobile, Medical syringes, Blood aspirators, Blender and mixer bowls.

5

ABS

1.05-1.07

40

320

15169

71-93

Pipe and fittings in drain waste and vent of buildings, Business machines, Computer housing, Electrical conduits.

6

Polymethyl Methacrylate (PMMA)

1.11-1.19

76

123

18715

54-110

Transparent like glass, Good weatherability, Glazing in aircrafts and boats, Skylight, Exterior lighting, Advertising signs, Auto tail light, Protective goggles.

7

Polytetrafluoro ethylene (PTFE, Teflon)

2.19

7.0-9.8

133-210

17730

288

High chemical resistance, Chemical piping, Pump parts, Electrical components, Cable insulation, Non-stick cooking utensile lining, Bearing seals, Bushings.

8

Phenolic (wood flour filled/glass filled/mica filled)

1.34-1.95

5-18

10.6-955

10,000-

15000

150-288

Connectors, Electrical switch gear, Telephone relays, Adhesive in

plywoods and binder of sand in foundary.

9

Polyster

(glass filled)

1.7-2.3

5-18

425-1150

1200-

1400

150-177

Good corrosion resistance, Pipes, Tanks, Ducts, Automobile body parts, Small boat hulls.

10

Melamine

1.5

5-13

10.6-26.5

6700-

1500

77-200

Knobs and handles, Moulded dinner wares, Binder in particle board, Boat hulls, Flooring.

11

Epoxy (without filler, glass/ mineral filled)

1.06-2.0

4-30

10.6-55

10700-

22000

120-260

Protective and decorative coating, Primer on automobile bodies, High voltage insulators in Switchgears


          Notice: Materials from Sl. No. 1 to 7 such are thermoplastics and Sl. No. 8 to 11 such are thermosetting plastics.Along with filler thermosetting plastics are used.


Related Discussions:- Engineering plastics

Explain principal process for electro chemical machining, Explain Principal...

Explain Principal Process for Electro Chemical Machining It is also called electrolytic machining or anodic cutting. This process is quite commonly used for shaping har

How is angle of dispersion used in footing, How is angle of dispersion used...

How is angle of dispersion used in footing? Angle of Dispersion Indian Standards (IS) has specified relation for determining the angle, of dispersion. According to IS the an

Som, a steel bar is

a steel bar is

A Composite from Multidirectional Laminates, A Composite from Multidirectio...

A Composite from Multidirectional Laminates                                              Figure: A Composite from Multidirectional Laminates Glass fibres usually u

Information dissemination, Information Dissemination The purpose of re...

Information Dissemination The purpose of record keeping is best served if information is timely disseminated. The employees are required to be informed on all health issues co

Determine the actual absolute velocity, Question: As shown in the figur...

Question: As shown in the figure, the jet transport B is flying north with a velocity v B = 600 km/h when a smaller aircraft A passes underneath the transport headed in the 60

Indicator diagram and indicated power - thermodynamics, Indicator diagram a...

Indicator diagram and indicated power: An indicated diagram is graph between pressure and volume. The former being taken on the vertical axis and latter on the horizontal axis

Thermodynamics, we can use in proove of energy is a propertyof system we ca...

we can use in proove of energy is a propertyof system we can use (E) instead of (dQ-dW)

Explain soft or flexible automation, Explain Soft or Flexible Automation? ...

Explain Soft or Flexible Automation? This system uses tape, a hand-held control box, microprocessors, programmable logic controllers or computers. The system can be reprogramme

Boiler, boiler performance.

boiler performance.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd