This set of Foundry Questions and Answers for Campus interviews focuses on “Binders and its Applications”.
1. _________________ is a binder that becomes firm at room temperature.
c) Rubber Latex
Explanation: Rubber Latex is rubber cement. Silica is mixed with water and this latex which is obtained of the plant is added to it. This mixture is then rammed and it hardens at the room temperature and has excellent binding properties.
2. __________ is a binder that becomes hard on baking.
a) Marine animal oil
b) Wood Resin
c) Oil Resin
d) Coal tar resin
Explanation: Marine animal oil is of the group of binders that do not develop their strength by any kind of physical or chemical changes, rather they are baked to harden them. Usually, Whale oil (Sperm oil) is used for binding applications.
3. Which of the following is not a protein binder?
Explanation: Molasses is a by-product of the sugar industry. After testing for its applications, molasses was not found to be protein rich; whereas the Gelatin got from meat, casein made from milk and the glue got from plants is all protein rich.
4. __________ is a binder made from starch.
a) Cereal Binder
c) Limed wood resin
Explanation: Dextrin is a carbohydrate which is produced by hydrolysis of starch or glucose. They are low molecular weight components and have significant binding properties. It is low cost and highly efficient binder.
5. _________________ are not pure binders but they serve to improve the collapsibility of the core.
a) Clay Binders
b) Saw dust and Wood flour
c) Marine Animal Oil
d) Sulfate Binder
Explanation: Saw dust and Wood flour have very little adhesive strength and it cannot perform well in complex application. It is rarely used for the chances of core collapsing are high. It is used in grain filler compounds only.
6. ______________ is the mechanical binder used in Masonry.
a) Bond stones
d) Silicon Fluoride
Explanation: Bond Stone is a stone which is strong and long enough to extend to the wall to its full thickness in order to join it. Hence it is used in Masonry.
7. _______________ is a binder that is used in the no-bake sand cores.
a) Gum Resin
b) Synthetic Resin
c) Coal tar Resin
d) Wood Resin
Explanation: The synthetic resins like phenol and urea formaldehyde are used as binders. They are mixed with hardeners to bring the chemical reaction. In this process, strength development takes place in a few minutes.
8. Which of the following is not a function of a core binder?
a) Hold the sand grains together
b) Give strength to the core
c) Not to impart collapsibility to core
d) Make cores to resist erosion and breaking
Explanation: Core is a disposable item used in Foundry. The core binder has a function of imparting adequate collapsibility to the cores before their purpose is served.
9. ____________ is fine pulverized material used as a binder.
b) Sodium Silicate
c) Iron Oxide
d) Silica Flour
Explanation: The Silica Flour is fine pulverized materials that are used greatly to increase the amount of oil necessary in oil sand mixtures. This binder is used only when the sand properties are fixed and it need not vary.
10. ___________ are polymerized to strong solids to be used as binders.
b) Fire Clay
c) Epoxy Resins
d) Phenol Formaldehyde
Explanation: Phenol Formaldehyde is synthetic resins which are thermosetting. They are dry powder or liquid. They are heated to get excellent binding properties.
Sanfoundry Global Education & Learning Series – Foundry and Forging.
To practice all areas of Foundry for Campus Interviews, here is complete set of 1000+ Multiple Choice Questions and Answers.