This set of Tricky Casting Questions and Answers focuses on “Methods of Ramming Mold Boxes – 2”.
1. Which of the following methods of ramming is suitable for the small batch production of castings?
a) Hand moulding
b) Squeezing
c) Jolting
d) Sand slinging
View Answer
Explanation: For the small batch production, it is very convenient to use the hand moulding method of ramming which is done manually and rest of the methods are mainly performed by the machines. So, it is very economical and time saving to use hand moulding for the small level production of castings.
2. Which of the following parts is used in jolt moulding to ram the sand in mould?
a) Biscuit
b) Jolt
c) Roller
d) Overhead hopper
View Answer
Explanation: Basically, an overhead hopper is used in jolt mould method of ramming, in which after filling the sufficient amount of sand to the mould, an overhead hopper is raised to a certain height and then it is allowed to free fall on to a solid bed plate, which results into the ramming and packing of sand layers in the mould.
3. Jolt method of ramming makes smooth ramming and packing of sand layers in the mould.
a) True
b) False
View Answer
Explanation: In the method of jolt moulding, it gives rise to uneven packing and it is very severe on the moulding equipment also. The sand at the bottom experiences the highest force and the magnitude of the force is decreases in upward direction, so the bottom layers packed well as compared to the top layers in the mould.
4. The jolt method of ramming can be suitable for horizontal surfaces in the mould.
a) True
b) False
View Answer
Explanation: In the jolt method of ramming, impact force is generated by the application of overhead hopper, this impact force compact the sand uniformly in the mould. This is achieved by continuous lifting and dropping of hopper and then the required hardness is achieved by the mould. Horizontal surfaces are mostly compatible or preferred for the optimization of this method.
5. The method of jolt ramming operates very leniently with the moulding equipment.
a) True
b) False
View Answer
Explanation: The method of jolt ramming is very severe on the moulding equipment because the lifting and dropping operations can affect the mould layers due to the impact forces, which abruptly disturb the mould material by the high magnitude of force, this can even lead to cracking and breaking of mould.
6. The problem with moulding equipment in jolt moulding can be avoided by implementing a squeeze method of ramming.
a) True
b) False
View Answer
Explanation: In squeeze ramming, a plate smaller than the inside dimensions of the moulding flask is fitted with the moulding sand. Then a uniform pressure is applied by the downward movement of a plate or by the upward movement of the flask itself, so this method avoids the damage to the moulding equipment.
7. In squeeze ramming, hardness achieved is inversely proportional to the pressure applied on the squeeze plate.
a) True
b) False
View Answer
Explanation: In squeezing method of ramming, the resulting force compact the sand uniformly and the hardness achieved directly depends to the pressure applied on the plate. More the pressure more will be the hardness of the sand, but the sand next to the plate rams hardest while the sand below is progressively less hard.
8. In squeeze ramming, plate is always provided with a contour to achieve a better hardness of the sand.
a) True
b) False
View Answer
Explanation: Generally, the hardness achieved follows the contour of the squeeze plate which is in contact with the sand, Contour is always provided with the plate to match the pattern to achieve a better uniform hardness of the mould. So, application of contour is very essential for better and efficient ramming.
9. Squeeze ramming is best for big castings and mainly suitable for high depth flasks.
a) True
b) False
View Answer
Explanation: Squeeze ramming is suitable for small castings and is generally suitable for shallow flasks which are of little depth. In this method of ramming, it is also possible to use a diaphragm to provide differential ramming force which is generally required for the contour of the pattern.
10. Which of the following is the best method for the uniform ramming of moulding sand?
a) Jolting
b) Squeezing
c) Sand slinging
d) Hand moulding
View Answer
Explanation: Sand slinging is defined as the combination of jolt and squeeze method of ramming, in which jolt-squeeze machines are used for the more uniform ramming. This is the method which is widely used in the ramming process, but the processes are expensive due to the application of various machines.
11. Sand slinging method is best, but the process takes too much time to accomplish the operation.
a) True
b) False
View Answer
Explanation: Sand slinging is a very fast method of ramming, it is done by throwing sand into the flask rapidly with the great force. This process develops uniformly high mould hardness. Sand slinging is the best method comparatively, but the cost of equipment used in this method is very high as compared to the other methods of ramming.
12. In sand slinging, which of the following parts is used for the spraying of moulding sand into the flask?
a) Biscuit
b) Runner
c) Diffuser
d) Nozzle
View Answer
Explanation: In the sand slinging method of ramming, the sand is uniformly sprayed into the mould by moving the nozzle through the entire area of the flask. Also, it is necessary that the sand is sprayed in layers to achieve uniform hardness. This method is very economical and widely used for ramming.
Sanfoundry Global Education & Learning Series – Casting, Forming and Welding.
To practice tricky questions and answers on all areas of Casting, here is complete set of 1000+ Multiple Choice Questions and Answers.
If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]
- Practice Casting, Forming and Welding II MCQ
- Check Mechanical Engineering Books
- Practice Mechanical Engineering MCQs
- Apply for Mechanical Engineering Internship
- Practice Metallurgical Engineering MCQs
