This set of Foundry Multiple Choice Questions & Answers (MCQs) focuses on “Moulding Machines”.
1. ______________ machine is used to ram sand in the mould box.
a) Jolt Machine
b) Sand Slinger
c) Core making machine
d) Squeezing machine
Explanation: Sand slinger is a machine which has a rapid rotating cup shaped blade that picks up the sand and throws it downward into the molding sand and throws it downwards with a great force and thus it rams the sand in the mould box.
2. In the sand slinger machine, the density of sand is a result of its ___________
Explanation: While the sand is rammed in the molding boxes using a sand slinger, sand is filled and rammed at the same time. The density of sand is the result of sand’s inertia which is uniform throughout the mould.
3. _________ machines are used for shallow patterns.
a) Core making machine
b) Sand Slinger machine
c) Squeeze machine
d) Jolt machine
Explanation: A squeezer, squeeze head plate or presser board slides inside the flask to compress the sand above and around the pattern. The presser plate exerts a substantial amount of pressure. The pressure can be easily distributed for the shallow patterns in a squeeze machine.
4. Which of the following mediums is not used for the power operated molding machines?
b) Hydraulic power
c) Compressed air
d) Sand Inertia
Explanation: The power operated molding machines are extension versions designed to overcome all the drawbacks of molding occurred by the traditional machines. The sand inertia is used for molding and is not a medium of machine whereas, the use of compressed air, hydraulic power or high impellor is used to obtain performance from power operated machines.
5. In a squeeze molding machine, the sand is rammed of the mould edge as well.
Explanation: The squeeze molding machine rams the sand harder at the back of the mold and softer on the pattern face. Sand has the greatest density at the surface where a pressure is applied to sand. In modern machines, the harder ramming on the mould edge is also ensured.
6. ___________ is used to obtain a uniform mold density in squeezer machine.
a) Sand paper
b) Flat plate
Explanation: In the squeezer machine, squeezing a flat plate produces non-uniform sand density and mold softness, whereas rubber diaphragm squeezing distributes squeeze molding forces more uniformly and thus a uniform mold density is obtained.
7. Which of the following is not a power operated machine?
a) Jolt machine
b) Sand Slinger
c) Pin lift machine
d) Jolt squeeze machine
Explanation: The pin lift machine is a hand molding machine. The operations and withdrawing of the pattern from the mould in the hand molding machine is accomplished mechanically which is the working phenomenon if pin lift machine.
8. The pattern equipment associated with the molding machines possesses longer life.
Explanation: All the castings produces using molding machines possesses correct and same size, shape, since no hand rapping is required to extract the pattern from the mold. Due to this, the pattern equipment has longer life.
9. Molding machine equipment is not as flexible as hand molding.
Explanation: Molding machine equipment is costlier than hand molding. Molding machine cannot be used for large and complex shapes. For the manufacturing of the large castings, hand molding process is to be employed.
10. ____________ establishes the most suitable gating system, riser etc are mounted on the match plate pattern itself.
a) Machine molding
b) Hand molding
c) Sand molding
d) Core molding
Explanation: Molding machines have patterns fixed on them which have inbuilt gating system and runner, gate etc that are mounted on the match plate itself. They perform their action rapidly and more accurately than the other types of molding.
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.