MOULD QUESTIONS
1) Which plastic materials contain strong cross linkings in their molecular structure?
a. Thermoplastic materials b. Thermosetting materials
c. Both a. and b. d. None of the above
2) Which of the following statements are correct for plastic?
1. Plastic is a non-metallic material that can be moulded to any shape
2. Plastic is a natural or synthetic resin
3. Plastic is of organic nature composed of hydrogen, oxygen, carbon and nitrogen
a. only statements 1 and 2 correct, statement 3 is wrong
b. only statements 1 and 3 correct, statement 2 is wrong
c. only statements 2 and 3 correct, statement 1 is wrong
d. all of above statements 1, 2 and 3 are correct
3) The plastics which soften when heat is applied with or without pressure, but requires cooling to set
them to shape are called as
a.thermosofting materials b. thermosetting materials
c. thermoplastic materials d.thermostatting materials
4) Thermosetting materials are
a. the plastics which can be softened even after they have set and hardened
b. the plastics which require heat and pressure to mould them into shape
c. both a. and b.
d. none of the above
5) Which of the following is an example of thermoplastic material?
a. Camera bodies b. Automobile parts
c. Electric plugs d. Electric insulation
6) Which of the following characteristics does not affect the properties of plastics?
a. Their molecular structure b. Their degree of polymerization
c. Both a. and b d. None of the above
7) Specific gravity of the plastics is usually
a. less than the specific gravity of metals b. more than the specific gravity of metals
c. similar to the specific gravity of metals d. Unpredictable
8) The process of combining two or more distinct polymer molecules to form a new product with
different characteristics is called as
a. binding b. stabilizing
c. filling d. blending
9) The materials such as lead and barium, which are added with polymers to minimize the effect of
heat, sunlight and ozone are called as
a. binders b. blenders
c. stabilizers d. fillers
10) Why are the plasticisers added with polymers?
a. To hold other constituents of plastic together
b. To reduce the cost and enhance the strength and hardness of plastics
c. To improve flexibility and to reduce the temperature and pressure required for moulding of plastics
d. None of the above
11) What do mean by Injection mould?
a. The moulding process in which material is charged in low pressure using machine nozzle.
b. The moulding process in which material is charged in high pressure using machine nozzle.
c. The moulding process in which material is charged manually.
d. None of these
12) What do you mean by family mould?
a. Mould in which more than one component is produced.
b. Mould in which different parts of a single component in produced.
c. Mould in which different types of components are produced.
d. None of the above
13) What do you mean by multi cavity mould?
a. Mould in which more than one ejector pins are used for a single component.
b. Mould in which more than one component is produced.
c. Both (a) and (b).
d. None of these.
14) The raw material to make plastic is oil.
a. TRUE b. FALSE
15) Plastic is suitable for building large and heavy structures.
a. TRUE b. FALSE
16) Epoxy resin is a thermoplastic?
a. TRUE b. FALSE
17) PVC is a thermoplastic
a. TRUE b. FALSE
18) HDPE is a tough plastic used for making toys
a. TRUE b. FALSE
19) Which process is used to manufacture plastic pipes?
a. Injection moulding b. Blow moulding.
c. Extrusion moulding d. Vacuum forming
20) Which of the following is used to manufacture carrier bags?
a. LDPE ( Low Density PolyEthylene) b. HDPE (High Density PolyEthylene)
c. Polycarbonate d. PVC
21) What do you mean by roto -core?
a. Rotating core and cavity b. Stationary core and cavity
c. Core with cam movement d. All of the above
22) On what occasion dog leg cam is used
a. Opening of core and cavity horizontally b. Opening of core and cavity vertically
c. Opening of core and cavity in a certain angle d. None of these
23) What do you mean by venting
a. process of removal of unwanted material
b. process of removal of gases present inside core and cavity
c. process of removal of toxic substances
d. all of the above
24) What do you mean by shrinkage?
a. reduction percentage of material after cooling
b. reduction percentage of material after heating
c. incremental percentage of material after cooling
d. reduction percentage of material after heating
25) Which of the following is used to make CDs?
a. PVC b. PTFE
c. Polycarbonate d. Polypropylene
26) Which of the following is used to manufacture carrier bags
a. LDPE ( Low Density PolyEthylene) b. HDPE (High Density PolyEthylene)
c. Polycarbonate d. PVC
27) What do you mean by family mould?
a. mould in which more than one component is made of same type.
b. mould in which all parts of same component is made.
c. mould in which similar component of different sizes are made.
d. None of these.
28) What is the function of wedging split cavity and side core
a. helps in movement of core and cavity in horizontally.
b. helps in movement of core and cavity in vertically.
c. helps in movement of core and cavity in angle.
d. all of these
29) Why vent is necessary?
a. For removal of unwanted material
b. For removal of gases present inside core and cavity
c. For removal of toxic substances
d. all of the above
30) Core & cavity of mould are generally made of what material?
a. OHNS b. H-13
c. Calmax d. All of these
31) Perspex is the trade name of
a. CA b. PA
c. PTF d. All of the above
32) What do you mean by runner layout?
a. layout being used for placing components b. layout being used for placing core cavity
c. layout being used for placing ejector pins d none of these
33) What do you mean by war page?
a. twisting effect in the component after molding b. ductility in the component after molding.
c. twisting effect in the material before molding d. None of these.
34) Nylon is the trade name of ----?
a. CA b. PA
c. PTFE d. All of the above
35) Delrin is the trade name of ----?
a. CA b. PA
c. POM d. All of the above
36) What is the function of locating ring of mould?
a. to locate sprue to core b. to locate machine nozzle to sprue
c. to locate cavity and sprue d. None of these
37) Which of the following is commonly used in schools for vacuum forming?
a. Melamine (MF) b. Thermoplastic
c. Polyester d. PVC
38) Teflone is the trade name of ……….?
a. CA b. PA
c. PTFE d. All of the above
39) Which plastic is used to laminate kitchen worktops?
a. Epoxy resin b. Melamine
c. PVC d. none of these
40) the advantages of plastics?
a. Low strength b. Low heat resistance
c. Poor mechanical properties d. Easily available
41) the disadvantages of plastics?
a. Low strength b. Low heat resistance
c. Poor mechanical properties d. All of the above
42) Give Example of thermoplastics
a. ABS b. PP
c. CA d. All of the above
43) Shrinkage value of HDPE
a. 3-4% b. 8-10%
c. 13-15% d. All of the above
44) Shrinkage value of HDPE
a. 0.8- 1.5% b. 5-10%
c. 3-5% d. All of the above
44) Shrinkage value of PC
a. 1-5% b. 0.5- 0.7%
c. 3-5% d. All of the above
44) Shrinkage value of PP
a. 1- 3% b. 5- 10%
c. 10- 15% d. All of the above
45) What are the divided sections of screw of injection molding machines?
a. Feed zone b. Compression zone
c. Melting zone d. All of the above
46) What is injection capacity or short capacity?
a. Maximum volume material injected by the screw during one cycle of operation.
b. Minimum volume material injected by the screw during cycle of operation.
c. Maximum volume material injected by the screw.
d. None of these
47) What is plasticizing capacity?
a. It is the amount of material that can be processed by the machine per hour.
b. It is the amount of material that can be processed by the core per min.
c. Both (a) & (b).
d. None of these.
48) What is maximum daylight?
a. distance between top surface of the top plate and bottom surface of the bottom plate.
b. distance between bottom surface of the top plate and top surface of the bottom plate.
c. Both (a) & (b).
d. None of these.
49) What are the general types of mold?
a. Injection molds b. compression molds
c. transfer molds. d. all of the above
50) What is undercut molding?
a. A molding which has a recess or projection is termed as an undercut molding
b. Any recess or projection on the outside surface of the component which prevents its removal
from cavity is termed an external undercut
c. Both (a) & (b)
d. None of these
51) Material for nozzle in hot runner mould is________________.
a. b.
c. d.
52) What is injection capacity or shot capacity?
a. Minimum volume material injected by the screw during two cycle of operation.
b. Volume material injected during cycle of operation.
c. Maximum volume material injected by the screw during one cycle of operation.
d. None of these.
53) What is plasticizing capacity?
a. It is the amount of material that can be processed by the machine per hour.
b. It is the amount of material that can be injected by the machine in every 5 hours.
c. Both (a) and (b).
d. None of these.
54) What is maximum daylight?
a. It is the maximum distance between top surface of the top plate and bottom surface of the
bottom plate.
b. It is the minimum distance between top surface of the top plate and bottom surface of the
bottom plate.
c. It is the maximum distance between machine platens in open condition.
d. It is the minimum distance between machine platens in open condition.
55) What is jetting?
a.
b. It is the prominent in-homogeneous snake like strands on the surface of moulding.
c.
d.
56) What is war page?
a. War page is the deviation of the mould part from its required shape.
b.
c.
d.
57) Where we use form pin straight action method?
a.
b.
c. For the components which has internal undercut on one side of the wall.
d.
58) What is weld line?
a.
b.
c.
d. It is the witness marks of two or more melt flow fronts at their joining zone.
59) What is Droolling?
a.
b.
c.
d.
