McqMate
201. |
High silicon irons are |
A. | resistant to wear |
B. | brown in colour |
C. | machinable |
E. | malleable |
Answer» A. resistant to wear |
202. |
Carbondioxide moulding is useful for |
A. | very thin sections |
B. | regular sections |
C. | heavy and thick walled sections |
D. | all of the above |
Answer» C. heavy and thick walled sections |
203. |
A drawback is employed when |
A. | the pattern is too bulky |
B. | the pattern is too long |
C. | the pattern is not made of wood |
D. | the pattern cannot be drawn from mould due to projection |
Answer» D. the pattern cannot be drawn from mould due to projection |
204. |
In furan moulding which of the following is used as a catalyst? |
A. | Potassium hydroxide |
B. | Phosphoric acid |
C. | Ammonium hydroxide |
D. | Phenol formaldehyde |
Answer» B. Phosphoric acid |
205. |
In case of copper, the pouring temperature is around |
A. | 1160?C |
B. | 1060?C |
D. | 1260?C |
E. | 1450?C |
Answer» A. 1160?C |
206. |
Polystyrene is generally available in the form of |
A. | trapezoidal moulds |
B. | square sections |
D. | plates |
E. | cylindrical bars |
Answer» D. plates |
207. |
If an old casting is to be used as a pattern, to account for various allowances. |
A. | to provide draw screws, holes can be drilled and tapped in the castings |
B. | the castings are cleaned and made smooth |
C. | casting is shaken while withdrawing from mould |
D. | the surfaces are lagged with thin strips of wood or leater |
Answer» D. the surfaces are lagged with thin strips of wood or leater |
208. |
The strength of the sand is high if grains are |
A. | round and small |
B. | sharp and irregular in shape |
C. | large and regular in shape |
D. | none of the above |
Answer» B. sharp and irregular in shape |
209. |
A mould which has good erosion resistance to metal flow and is also collapsible is |
A. | green sand mould |
B. | skin dry sand mould |
C. | dry sand mould |
D. | none of the above |
Answer» B. skin dry sand mould |
210. |
During the passage of molten metal through the coke, the carbon percentage of the molten metal increases. The absorption of carbon depends on |
A. | size of the coke |
B. | temperature |
C. | time allowed for molten metal to remain in the cupola |
D. | all of the above |
Answer» D. all of the above |
211. |
Hot spots are generally found in castings |
A. | symmetrical about two axes |
B. | having abrupt variation in section |
C. | with uniform cross-section |
D. | small in weight but large in volume |
Answer» B. having abrupt variation in section |
212. |
Which of the following metals has the lowest melting point? |
A. | Tin |
B. | Silver |
C. | Zinc |
D. | Magnesium |
Answer» A. Tin |
213. |
Slag in a blast furnace is |
B. | lighter than molten iron |
D. | heavier than molten iron |
Answer» B. lighter than molten iron |
214. |
Sprues are generally |
A. | tapered upwards |
C. | tapered downwards |
E. | uniform size |
Answer» C. tapered downwards |
215. |
When bench moulding is adopted using three boxes, the central box is called |
A. | cope |
B. | cheek |
C. | drag |
D. | none of the above |
Answer» B. cheek |
216. |
Cores are made from core sand mixed with the binder which may be |
A. | linseed oil |
B. | turpentine |
C. | cement |
D. | none of the above |
Answer» A. linseed oil |
217. |
Thermal efficiency of cupola is in the range |
A. | 30 to 50 percent |
B. | 60 to 75 percent |
C. | 50 to 65 percent |
D. | 80 to 90 percent |
Answer» A. 30 to 50 percent |
218. |
Which of the following sand must possess high refractoriness? |
A. | Backing sand |
B. | Parting sand |
C. | Facing sand |
D. | all of the above |
Answer» C. Facing sand |
219. |
The rammer used for packing the sand in pockets/corners of a mould is known as |
B. | Floor rummer |
C. | Hand rammer |
D. | Peen rammer |
Answer» D. Peen rammer |
220. |
Normal shrinkage allowance for aluminium is 18 mm per metre and that for cast iron 10 mm per metre. If the metal pattern is to be made of aluminium and the casting is to be of cast iron, the shrinkage allowed on wooden master pattern will be |
A. | 10 mm/metre |
B. | 28 mm/metre |
C. | 8 mm/metre |
E. | 18 mm/metre |
Answer» B. 28 mm/metre |
221. |
Which of the following defect is likely to occur due to improper design of gatting system? |
A. | Shrinkage |
B. | Porosity |
C. | Mould erosion |
D. | any of the above |
Answer» D. any of the above |
222. |
White cst iron contains |
A. | free graphite |
B. | cementite |
C. | free carbon |
D. | none of the above |
Answer» B. cementite |
223. |
A slick is mainly used for |
B. | repairing and finishing of mould |
C. | removing pattern from the mould |
D. | making openings in mould |
E. | providing openings in the mould |
Answer» B. repairing and finishing of mould |
224. |
The cross-section of a sprue |
A. | square |
B. | circular |
C. | rectangular |
D. | any of the above |
Answer» D. any of the above |
225. |
Grey cast iron is |
A. | resistant to shock |
B. | least fluid in molten condition |
D. | poor in machining ability |
E. | costlier than other varieties of cast iron |
Answer» A. resistant to shock |
226. |
Malleable castings are used for |
A. | boilers |
B. | Automobiles |
C. | Elevators |
D. | all of the above |
Answer» D. all of the above |
227. |
All of the following are boring tools EXCEPT |
A. | Gauge |
C. | Pinchdog |
D. | Brace |
E. | Auger bit |
Answer» C. Pinchdog |
228. |
Tempering is generally done to reduce all of the following EXCEPT |
A. | Hardness |
B. | Brittleness |
C. | Tensile strength |
D. | Ductility |
Answer» D. Ductility |
229. |
The solidification shrinkage of carbon steel is around |
B. | 0.5 to 1 percent |
C. | 2 to 4 percent |
D. | 8 to 10 percent |
E. | 0.1 to 0.2 percent |
Answer» C. 2 to 4 percent |
230. |
The draft allowance to be provided on a pattern depends on |
A. | the length of the vertical side of the pattern to be extracted |
B. | the intricacy of the pattern |
C. | the method of moulding |
D. | all of the above |
Answer» D. all of the above |
231. |
Magnesium aluminium alloys are grain refined by addition of |
A. | manganese |
B. | sulphur |
C. | carbon |
E. | tin |
Answer» C. carbon |
232. |
The advantage of oxygen enriched cupola is |
A. | higher temperature of molten iron |
B. | high efficiency of cupola |
C. | reduced heat loss in waste gases |
D. | all of the above |
Answer» D. all of the above |
233. |
The contraction allowance for pattern depends on |
A. | composition of the metal |
B. | method of moulding used |
C. | pouring temperature |
D. | all of the above |
Answer» D. all of the above |
234. |
The advantage of shell moulding is |
A. | Less sand requirement |
B. | Process can be used for all cast metals |
C. | Good accuracy of dimensions |
D. | All of the above |
Answer» D. All of the above |
235. |
Providing more than adequate machining allowance |
B. | reduces machining cost |
C. | increases machining cost |
D. | improves the strength of the casting |
E. | reduces the strength of the casting |
Answer» C. increases machining cost |
236. |
As a result of melting in cupola, the percentage of all of the following constituents decreases EXCEPT |
A. | Sulphur |
B. | Silicon |
C. | Phosphorous |
E. | Carbon |
Answer» E. Carbon |
237. |
Chaplets are provided to |
A. | reduce core sag |
B. | support heavy cores |
C. | compensate for inadequate coreseats |
D. | all of the above |
Answer» D. all of the above |
238. |
Polystyrene often used as a consumable pattern material has a relative density of |
A. | 20 to 25 kg/m3 |
C. | 2240 to 2500 kg/m3 |
D. | 120 to 125 kg/m3 |
E. | 1120 to 1125 kg/m3 |
Answer» A. 20 to 25 kg/m3 |
239. |
For stress relieving, castings are |
A. | heated to low temperature and furnace cooled |
B. | heated to a temperature around melting point and slowly cooled |
C. | heated in stages and also cooled in stages |
E. | heated by flame and air cooled |
Answer» A. heated to low temperature and furnace cooled |
240. |
Gated patterns are normally used for |
A. | castings for light metals |
B. | castings having several hollow spaces |
C. | mass production of small castings |
D. | production of castings which do not require machining |
Answer» C. mass production of small castings |
241. |
Casting made in relatively simple shapes and designed for subsequent fabrication by rolling, forging etc. are known as |
A. | rolls |
C. | pigs |
D. | ingots |
E. | chills |
Answer» D. ingots |
242. |
Which of the following is used as protective admixture in moulding sand for magnesium castings? |
A. | Boric acid |
B. | Sublimed sulphur |
C. | Fluoric additives |
D. | Any of the above |
Answer» D. Any of the above |
243. |
For sterite refractory bricks are attacked by |
A. | basic slags |
B. | acid slags |
C. | alkali compounds |
D. | all of the above |
Answer» B. acid slags |
244. |
Which of the following is the anti-penetration material introduced in the moulding sand? |
A. | Coad dust |
B. | Powdered quartz |
C. | Black oil |
D. | all of the above |
Answer» D. all of the above |
245. |
The property of sand to withstand the high temperature of the molten metal without fusing or breakdown is known as |
A. | porosity |
C. | refractoriness |
D. | cohesiveness |
E. | adhesiveness |
Answer» C. refractoriness |
246. |
Addition of nickel to cast iron increases |
A. | hardness |
B. | corrosion resistance |
C. | tensile strength |
D. | all of the above |
Answer» D. all of the above |
247. |
A casting process which can produce hollow cylinder without use of core is |
A. | permanent mould casting |
B. | semi permanent mould casting |
C. | pressed casting |
D. | none of the above |
Answer» D. none of the above |
248. |
The advantage of centrifugal casting is |
A. | dense castings |
B. | elimination of cores |
C. | mass production with reduced rejection possible |
D. | all of the above |
Answer» D. all of the above |
249. |
All of the following are non-destructive method of testing the castings EXCEPT |
B. | Dye penetrant inspection |
C. | Pressure test |
D. | Ultrasonic test |
E. | Tensile test |
Answer» E. Tensile test |
250. |
Which of the following is not necessarily the characteristic of investment casting? |
A. | No disfiguring parting line as found on castings made by cope and drag methods |
B. | Extreme dimensional accuracy |
C. | Excellent surface finish |
D. | Low cost |
Answer» D. Low cost |
251. |
Pattern draft for internal surfaces is (in mm/m) |
A. | 10 -- 30 |
C. | 50 - 80 |
E. | 40 - 70 |
Answer» E. 40 - 70 |
252. |
On drying the shrinkage of wood is least |
B. | along the grains |
C. | across the grains |
E. | along the direction of tangent to the annular rings |
Answer» B. along the grains |
253. |
Contraction of metal starts at the end of |
B. | mushy stage |
C. | plastic stage |
D. | liquid stage |
E. | solid stage |
Answer» B. mushy stage |
254. |
In radiography test on castings which of the following rays are never used? |
A. | X-rays |
B. | beta rays |
C. | gamma rays |
D. | all of the above |
Answer» B. beta rays |
255. |
Metal moulds are used in |
A. | dry sand moulding |
B. | green sand moulding |
C. | die casting process |
E. | loam moulding |
Answer» C. die casting process |
256. |
The defect known as 'drop' occurs when the upper surface of the mould cracks and pieces of sand fall into the molten metal. This defect occurs due to |
A. | low mould hardness |
B. | insufficient reinforcement |
C. | low green strength |
D. | any of the above |
Answer» D. any of the above |
257. |
Investment casting finds application in all of the following EXCEPT |
A. | Jet engine nozzles |
C. | Milling cutters |
D. | Buckets for superchargers |
E. | Gold ornaments |
Answer» E. Gold ornaments |
258. |
Lowest pouring temperature alloy is |
A. | Phosphor bronze |
B. | Cupro nickel alloy |
C. | Monel metal |
D. | Tin bronze |
Answer» C. Monel metal |
259. |
The residual stresses in casting occur due to |
A. | sand particles being taken into molten metal while pouring |
B. | the insufficient gate size |
C. | the differential solidification rate of thin and thick sections of casting |
D. | none of the above |
Answer» C. the differential solidification rate of thin and thick sections of casting |
260. |
Local stress relief treatments are generally given to |
A. | small castings |
C. | non-ferrous castings |
D. | all castings |
E. | too large castings |
Answer» E. too large castings |
261. |
Which of the following is used on moulds for magnesium castings to prevent metal mould reactions? |
A. | Boric sulphur |
B. | Molasses |
C. | Charcoal |
D. | all of the above |
Answer» A. Boric sulphur |
262. |
Silica is the second most important constituent of moulding sand which provides |
A. | binding strength |
B. | refractoriness |
C. | chemical resistance |
D. | none of the above |
Answer» A. binding strength |
263. |
Flash occurs on diecastings at the |
B. | gatting system |
C. | ejection pins |
D. | vents between the dies |
E. | parting surface of two dies |
Answer» E. parting surface of two dies |
264. |
The methods of casting for producing ornamental pieces are |
A. | pressed and slush casting |
B. | slush and gravity casting |
C. | gravity and semi permanent mould casting |
D. | none of the above |
Answer» A. pressed and slush casting |
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