Salvaging Techniques MCQs : Here you will find MCQ Questions related to "Salvaging Techniques" in Casting, Forming & Welding. These Salvaging Techniques MCQ Questions Will help you to improve your Casting, Forming & Welding knowledge and will prepare you for various Examinations like Competitive Exams, Placements, Interviews and other Entrance Exmaniations.
Question 1
In the soldering process, the solder gets melted, when the temperature goes below?
A. 700°F
B. 800°F
C. 900°F
D. 600°F
View Answer
Ans : B
Explanation: The process of soldering is very much similar to that of brazing, except for the temperature difference. In the soldering process, the solder gets melted, when the temperature goes below 800°F.
Question 2
Which are the one of the techniques used for salvaging defective castings?
A. Caulking
B. impregnation
C. Both A and B
D. None of the above
View Answer
Ans : C
Explanation: Caulking and impregnation are one of the techniques used for salvaging defective castings. Among the following, linseed oil, sodium silicate and synthetic resins are regularly used as impregnants, but not sodium carbide.
Question 3
In impregnation technique of salvaging casts, the material has to be kept immersed inside the sodium silicate solution at a temperature between 175°F to 200°F, for about?
A. 1 hour to 3 hours
B. 2 hour to 4 hours
C. 3 hour to 5 hours
D. 4 hour to 6 hours
View Answer
Ans : B
Explanation: In impregnation technique of salvaging casts, the material has to be kept immersed inside the sodium silicate solution at a temperature between 175°F to 200°F, for about 2 hours to 4 hours.
Question 4
Which of the following is true?
A. Salvaging through welding is mainly focused on high alloy steels.
B. Filling can be used for non-ferrous alloys.
C. Both A and B
D. None of the above
View Answer
Ans : C
Explanation: Both A and B statement are true.
Question 5
Which of the following is not an important property in terms of filler metals?
A. Thermal resistance
B. Chemical resistance
C. Corrosion resistance
D. Appearance
View Answer
Ans : A
Explanation: When filler metals are considered, one has to be very careful while operating on it, as they play an important role in the weld characteristics. The thermal resistance has to be taken into account, but not as much as chemical resistance or corrosion resistance or the appearance of it.
Question 6
Which statement is false?
A. A metallic powder is basically used as a coating for the heat transfer enhancement.
B. In electric arc wire spray process, the atomizing air pressure is the only significant variable for controlling the surface layers.
C. Both A and B
D. In salvaging of castings, cooling fluid used can be directly exposed to the hot castings to enhance heat transfer
View Answer
Ans : D
Explanation: A cooling medium like coolant air from the compressor or steam is commonly directed to the casting along one or more casting surfaces. This flow for cooling is considered as backside flow, where the cooling medium is not directly exposed to the high temperature of surfaces of the casting.
Question 7
Which of the following parts of castings are mostly salvaged with defective cast cooling bumps?
A. Piston
B. Cylinder
C. Connecting rods
D. Gas turbine parts
View Answer
Ans : D
Explanation: In salvaging of gas turbine castings, parts are exposed to the one side where high-temperature fluid medium has cast-in bumps on an opposite cooling surface side to increase heat transfer rate. This makes uniform cooling of the casted product to have negligible defects in the casting.
Question 8
Which of the following types of inspection is mostly used for the identification of cast bumps on the castings?
A. Radiography
B. Eddy current method
C. Visual inspection
D. Dimensional inspection
View Answer
Ans : C
Explanation: The surface areas of casting manifested by one or more partially cast bumps are first identified by visual inspection or sometimes by thermo-graphy. After identification, the areas are cleaned and the defective bumps are removed by the machining operations like grinding and grit blasting.
Question 9
In salvaging process, the metallic particles used for enhancing heat transfer may stick to the surface areas of casting by melting itself.
A. TRUE
B. FALSE
C. Can be true or false
D. Can not say
View Answer
Ans : B
Explanation: In the salvaging process, the metallic particles are always chosen to withstand the casting operating conditions while providing a high thermal conductivity that enhances heat transfer. The metallic particles must withstand the casting or part operating temperature while not diminishing other part properties.
Question 10
This metallic coating provides _______ improvement in heat transfer which forms the casting defects free and highly efficient.
A. 5-10%
B. 10-30%
C. 30-50%
D. 1
View Answer
Ans : C
Explanation: In order to boost heat transfer by salvaging of castings, the average coating thickness of metallic particles must be at least about 0.2 mm and less than about 0.4 mm. This metallic coating provides 30-50% improvement in heat transfer which forms the casting defects free and highly efficient.