Casting, Forming and Welding Multiple Choice Questions & Answers (MCQs) on “Salvaging Techniques”.
1. Which of the following welding method is not used for salvaging?
a) TIG welding
b) MIG welding
c) Gas welding
d) Oxy-hydrogen welding
Answer: d
Clarification: In casting processes, there are many occasions on which a lot of material is wasted. Among the following, TIG welding, MIG welding and gas welding, are a few methods used in salvaging welding.
2. Which of the following is not a method of preparation of defective areas?
a) Chipping
b) Grinding
c) Rolling
d) Gouging
Answer: c
Clarification: In salvaging techniques, when a particular part has to be welded. Before the beginning of the weld, the defective part has to be prepared for it. Chipping, grinding and gouging are a few types of doing it.
3. Which of the following method is most suited for salvaging?
a) Brazing
b) Welding
c) Caulking
d) Plugging
Answer: b
Clarification: It is observed that, when the material which has been wasted, to be able to bring it to use, with the help of salvaging techniques, welding serves as the most appropriate operation than all others.
4. 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
Answer: a
Clarification: 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.
5. Below what temperature does a solder melt?
a) 500°F
b) 600°F
c) 700°F
d) 800°F
Answer: d
Clarification: 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.
6. Which of the following is not an impregnant?
a) Linseed oil
b) Sodium silicate
c) Silicon carbide
d) Synthetic resin
Answer: c
Clarification: 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.
7. At what temperature, is sodium silicate immersed in the cast for salvaging?
a) 125°F
b) 175°F
c) 225°F
d) 275°F
Answer: b
Clarification: Sodium silicate is a type of impregnant, used for salvaging. The use of sodium silicate to immerse in the cast is termed as impregnation. The temperature at which this immersion should take place is between 175°F to 200°F.
8. For what time is a cast kept immersed in sodium silicate solution for salvaging?
a) 1 hour to 3 hours
b) 2 hours to 4 hours
c) 3 hours to 5 hours
d) 4 hours to 6 hours
Answer: b
Clarification: 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.
9. Salvaging through welding is mainly focused on high alloy steels.
a) True
b) False
Answer: a
Clarification: Salvaging techniques, use the generated waste from casting processes in useful means by performing various operations on it like, welding, brazing and so on. Welding operation for salvaging is most suited for high alloy steels and more to iron.
10. Filling can be used for non-ferrous alloys.
a) True
b) False
Answer: a
Clarification: There is some sort of preparation required to the defective parts of the metal before it is put for welding. When non-ferrous materials are to be prepared, filling serves as an option, before it is welded. Grinding is also one of the options for preparing non-ferrous materials.