This set of Foundry Multiple Choice Questions & Answers (MCQs) focuses on “Cores and Core Prints”.
1. ___________ forms a seat in mold on which the sand core rests during pouring.
d) Core Print
Explanation: The core print is just like an added projection on the pattern and it must be of the adequate size and shape so that it can support the weight of the core during the casting operation.
2. Which of the following is a property of core material used in a foundry?
a) Appropriate for long production
b) Low Weight
d) Core Print
Explanation: The core materials are always composites skins which create a sandwich structure. The main property looked for its functionality is the high stiffness and low weight.
3. The use of cores is always dependent on the type of sand used.
Explanation: The design of the casting depends upon the area where it is supposed to be used. Hence, the sand type is a major function of the foundry. The core is dependent on the sand as it comes in contact with it.
4. The _______ is responsible for cavities in castings in the foundry.
Explanation: In a foundry, a core is usually placed in the mould box as a separate entity or the integrated part of the pattern to form a castings that has intricate parts and when it requires to produce internal cavities and reentrant angles.
5. A core is a disposable item but it can be reused from time to time.
Explanation: A core is a device which is normally made up of sand. The technology of metallic cores is emerging in manufacturing technology. The core when used once usually comes out in the burnt form and hence even though it is disposable, it cannot be reused.
6. The number of cores to be used to form castings is _____________
c) Depends on the sand
d) Depends on the design
Explanation: The number of cores used in the formation of the casting depends hugely on the design. The range of the cores used cannot be specified. The valves require two or three cores depending on the design where as the GM V-8 engines require 5 dry sand cores.
7. ___________ cores cannot make long narrow features.
a) Green Sand
Explanation: The Green sand cores make a casting of the long narrow features difficult or impossible. Even for long features that can be cast, it will still leave much material to be machines.
8. Which of the following process is not used to remove the cores from the finished casting?
d) Chemical Dipping
Explanation: When the air is blown, the particles of the burnt core are removed. Similarly, the washing and chemical methods are used when the adhesive properties of the core particles are high. The core melts when the hot metal is poured over it. Hence, this process cannot be used for cleaning.
9. The dimensional accuracy of the cores is low.
Explanation: The foundry procedures are tedious and difficult. The cores are required to produce the intricacies and cavities. The cores are produced by using the sand and other such materials and hence the dimensional accuracy of the cores in such cases becomes low.
10. Binders are added to increase the strength of the core.
Explanation: The foundry process requires binders for almost every application. The making of the cores requires binders for the making of cores. The binder quantity increases the adhesive properties of the core and it can be used to increase the dimensional accuracy of the cavity.
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.