Casting, Forming and Welding Multiple Choice Questions & Answers (MCQs) on “Injection Moulding Process”.
1. How is the die used in injection molding cooled?
a) Oil
b) Air
c) Water
d) Contact with cold surface
Answer: c
Clarification: When it comes to molding of polymers in thermoplastics, injection molding process is the most common of the methods. In this method, whenever the die has to be cooled, there is water used to cool it.
2. How does the piston in the clamping unit move?
a) Hydraulic energy
b) Pneumatic energy
c) Heat energy
d) Suction
Answer: a
Clarification: There is a clamping unit employed for holding the two halves together and for the opening and closing of the mold. A moving piston is provided which operates the power press. This piston works on hydraulic energy.
3. Where does the granular molding material get loaded into?
a) Barrel
b) Hopper
c) Pellets
d) Split
Answer: b
Clarification: In a ram or plunger type injection molding system, the granular molding material has to be first loaded into a hopper, after which, with the help of a feeding device it gets metered out inside a cylinder.
4. Which of the following material is not made by injection molding?
a) Nuts
b) Tubes
c) Car handles
d) Electrical fittings
Answer: b
Clarification: Injection molding is one of the most widely used method of molding among molding with polymers. There are various applications of this method such as nuts, bolts, cups, car handles, electrical fitting parts, but not tubes and rods.
5. What is the minimum temperature allowed to be given to the injection molding process?
a) 120°C
b) 130°C
c) 140°C
d) 150°C
Answer: d
Clarification: In the molding process of polymers in thermoplastics, injection molding process is the most common of the methods. The minimum allowable temperature that can be given to the system is 150°C.
6. Which of the following factors is not considered in a ram type injection molding?
a) Inner pressure of material
b) Outer pressure of material
c) Volume of material
d) Temperature of material
Answer: c
Clarification: Among the following, the inner pressure of the material, the outer pressure of the material as well as the mold and the temperature of the material and mold are important factors to be considered. The volume of material is not counted among important factors.
7. What is the minimum pressure allowed to be given to the injection molding process?
a) 90 MPa
b) 100 MPa
c) 140 MPa
d) 170 MPa
Answer: b
Clarification: None.
8. What is the maximum temperature allowed to be given to the injection molding process?
a) 300°C
b) 320°C
c) 350°C
d) 400°C
Answer: a
Clarification: The maximum allowable temperature that can be given to the system is 300°C, in this particular method of molding.
9. The barrel is used for the opening and closing of the mold.
a) True
b) False
Answer: b
Clarification: A barrel is an instrument that is placed near the nozzle, and it plays no role in the opening and closing of the mold. There is a clamping unit employed for holding the two halves together and for the opening and closing of the mold.
10. There is a varied pressure provided in the solidification unit of injection molding process.
a) True
b) False
Answer: b
Clarification: Injection molding is considered to be one of the most widely used methods. In this method, there are dies that eject the solidified component, before which it is kept under constant pressure.