1. Black color is generally painted on
a. oxygen cylinder b. acetylene cylinder c. hydrogen cylinder d. none of the above
2. Maroon colour is generally painted on
a. oxygen cylinder b. acetylene cylinder c. hydrogen cylinder d. none of the above
3. Ratio of oxygen to acetylene for complete combustion is:
a. 1:1 b. 1.5:1 c.2:1 d. 2.5:1
4. Filler material is essentially used in
a. gas welding b. spot welding c. seam welding d. all of the above
5. Generally the oxy-acetylene welding done with
a. neutral flame b. oxidising flame c. carburizing d. all of the above
6. Neutral flame is obtained by supplying
a. equal volumes of oxygen and acetylene b. more volume of acetylene and less volume of oxygen
c. more volume of oxygen and less volume of acetylene d. none of the above
7. Carburising flame is obtained by supplying
a. equal volumes of oxygen and acetylene b. more volume of acetylene and less volume of oxygen
c. more volume of oxygen and less volume of acetylene d. none of the above
8. Oxidising flame is obtained by supplying
a. equal volumes of oxygen and acetylene b. more volume of acetylene and less volume of oxygen
c. more volume of oxygen and less volume of acetylene d. none of the above
9. Neutral flame is used to weld
a. copper or brass b. cast iron c. steel d.all of the above
10. Carburising flame is used to weld
a. steel, cast iron, copper etc . b. brass and bronze/c c. hard surfacing materials such as stellite
d. all of the above
11. Oxidising flame is used to weld
a. brass b. copper c. bronze d. all of the above
12. If the weld is made from left to right, it is known as
a. fore-hand welding b. back-hand welding c. vertical welding d. none of the above
13. If the weld is made from right to left, it is known as
a. fore-hand welding b. back-hand welding c. vertical welding d. none of the above
14. Arc length in arc welding should be equal to
a. half the diameter of electrode rod b. rod diameter c. twice the rod diameter
d. 2.5 times the rod diameter
15. Magnetic arc blow is
a. a recent welding technique b. used to weld hard materials
c. phenomenon of-occurrence of splatter because magnetic fields created in D.C. arc welding
d. of importance during striking of arc
16. In coated electrode In arc welding
a. both rod and coating melt simultaneously b. coating melts first and then rod melts
c. which melts first depends on polarity used d. rod melts first and then coating melts
17. In reverse polarity welding
a. electrode holder is connected to the negative and work to positive
b. electrode holder is connected to the positive and work to negative
c. work is positive and holder is earthed d. holder is positive and work is earthed
18. Melting point of the filler metal in brazing should be above
a. 420.C b. 600.C c. 800.C d. 900.C
19. Most commonly used flame in gas welding is
a. Neutral b. oxidizing c. Carburizing d. all of the above
20. Filler metal is used in
a. Electric spot welding b. Seam welding c. Projection welding d. None of the above
21. Arc length in electric arc welding is the distance between the tip of the electrode and the
a. work piece b. center of crater c. bottom of crater d. work piece minus electrode diameter
22. Material best weld able with it self is
a. stainless steel b. copper c. bronze d. mild steel
23. Oxy-acetylenes flame cuts metals by its
a. evaporation b. oxidation c. burning d. intensive oxidation
24. Gas torch is usually lighted by a friction lighter because
a. it is easier to operate and maintain b. of low initial cost c. spark is created for very short duration
d. of safety of operator