This set of Foundry Multiple Choice Questions & Answers (MCQs) focuses on “Patterns and its Functions”.
1. _________________ is termed as a replica of the object to be made by the casting process.
Explanation: A Patten is a casting double which has allowances, provision of the core prints which is used to make a casting. It is a replica into which molten metal will be poured during the casting processes and later the metal is hardened and a component is obtained.
2. The final dimensions of the pattern are ______ the final dimensions of the casting required.
a) Similar to
b) Different from
c) Equal to
d) Approximate to
Explanation: The Pattern is made given the allowances as required. Once the casting is prepared, the casting is machined to get the required dimensions. Usually, the dimensions of the pattern are more than the dimensions of the castings.
3. The contractions in the materials depend upon the metallurgical transformation taking place during which of the following process?
Explanation: When a metal undergoes solidification, it undergoes a decrease in volume which is called contraction and hence is it is a major parameter in the metallurgical transformation which is taken into consideration while designing any component for foundry applications.
4. The shrinkage value given to the pattern must be _________ for the outer dimensions which are to be restrained.
d) Does not alter anything
Explanation: In a dry sand core, the centre of the casting may restrain the casting from the contraction but the edges are not restrained. Thus, it is desirable to provide a higher shrinkage allowance.
5. ______________ is used to reduce the chances of damaging the mould cavity.
a) Draft Allowance
b) Shrinkage Allowance
c) Finish Allowance
d) Machining Allowance
Explanation: At the time of withdrawing a pattern from the sand mould, the vertical faces of the pattern are in continual contract with sand which damages the mould cavity. Hence the pattern is tapered from the parting line and it is called as the draft allowance.
6. ______________ pattern is expected to be entirely in the drag.
a) Single piece pattern
b) Split piece pattern
c) Gated piece pattern
d) Match plate pattern
Explanation: Single piece pattern is used for various applications. As one of the surfaces is expected to be flat the single piece pattern is expected to be in drag Sometimes the flat surface of the Single piece pattern could also be made to function as a parting line.
7. The split piece pattern is aligned perfectly using ________
a) Screw Pins
b) Dowel Pins
d) Straight pins
Explanation: The dowel pins match with the precisely made holes in the drag half of the pattern and thus align the two halves (cope and drag). The dowel pins are used as location guides for the adjustments of the cope and the drag.
8. _________ is used for the pattern in the full mould process.
b) Polysilicate foam
c) Polyurethane foam
d) Polystyrene foam
Explanation: In the full moulding process, the foam evaporates soon after the metal is poured. Hence Polystyrene foam is used as it is light and can easily be formed into any shape required. It can be used as light duty work for small castings.
9. Hand cutting of runners and gates is eliminated in ______________
a) Split Pattern
b) Single piece pattern
c) Gated Pattern
d) Match Plate Pattern
Explanation: Gated Pattern is an improvement over simple pattern where gating and runner system is integral with a pattern. A Gated Pattern consists if the moulding and control patterns, jigs, the drying plates and the stripping place all embedded in it.
10. __________ is a mould forming tool is the hand of Foundry men.
d) Gating System
Explanation: Mould forming is a one by which the design of the casting which is to be produced is formed. The Pattern is one of the most important parts of the process by which the mould is formed. Hence the foundry men popularly call it as a mould forming tool.
Sanfoundry Global Education & Learning Series – Foundry and Forging.
To practice all areas of Foundry and Forging, here is complete set of 1000+ Multiple Choice Questions and Answers.