9. The frequency of up and down vibration of the cutting edge in a nibbling machine is…
A. 1000 to 1500 times
B. 1500 to 2500 times
C. 2800 to 3000 times
D. 3000 to 3500 times
10. Name the instrument used to check the perpendicularity of the branch pipe with the main pipe of a pipe T joint
A. protractor
B. try square
C. spirit level
D. straight edge
11.Which type of notch is used when a single hem meets at right angles?
A. V notch
B. slit notch
C. slant notch
D. square notch
12. To cut out small apertures which punch and die type of machine is used?
A. shear type nibbler
B. punch type nibbler
C. circular cutting machine
D. guillotine shearing machine
13. The overheating of the blow pipe nozzle is to be avoided because it will
A. cause back fire
B. consume more oxygen and acetylene
C. create burn through defect in the joint
D. create undercut defect in the joint
14. State the nozzle size you will select to weld a 3.15mm thick mild steel sheet
A. 3
B.5
C. 7
D. 10
15. The type of flame to be set for welding brass is…
A. air acetylene flame
B. neutral flame
C. oxidizing flame
D. carburizing flame
16. What is the maximum thickness of mild steel sheet recommended for gas welding using leftward technique?
A. 12mm
B. 10mm
C. 8mm
D. 5mm