WorksheetsWelding and Brazing Multiple Choice Questions
Total questions: 20
Worksheet time: 10mins
A gas welding setup operates mainly by combining:
Two gases under control
A pump and a burner unit
A cylinder and a cooler pipe
An electric arc and an air jet
In oxy-acetylene welding, oxygen is used to:
Raise the flame heat level
Reduce metal surface oxides
Create a cooling boundary film
Maintain a low combustion rate
Compared to welding, brazing is performed:
At a lower joining heat range
With a stronger filler layer
In an enclosed shielded zone
Using only mechanical joints
Copper tubes are commonly joined by brazing because:
Heat damage is minimized
Surface color is improved
Joint size is increased
Gas use becomes less costly
Oxygen and acetylene hoses are identified by color to:
Prevent wrong gas connection
Lower system gas pressure
Increase flame stability
Improve cylinder balance
A neutral flame is recognized when:
Inner cone is clearly defined
Outer edge shows dark blue
Flame burns with sharp sound
Tip glows with orange hue
The function of a flashback arrestor is to:
Stop flame return to hoses
Maintain steady gas supply
Increase torch cooling rate
Support flame cone formation
Before brazing, copper tubes must be:
Cleaned and properly aligned
Slightly cooled and pressurized
Marked and coated with oil film
Rolled and capped with plugs
Correct flame adjustment is achieved by:
Balancing oxygen and acetylene
Tilting torch at higher angle
When cutting a 10 mm steel plate, gas pressure must be:
Set according to plate thickness
Maintained at lowest safe rate
Equal to acetylene flow rate
Adjusted by sound of flame
If a torch backfires, the first action is to:
Close both gas valves safely
Tap the nozzle lightly
Raise torch away from metal
Increase gas flow instantly
Oxidation during brazing is prevented by:
Applying proper flux layer
Using higher torch angle
Cooling joint under water
Adding extra filler metal
The quality of a soldered joint depends on:
Cleanliness and temperature
Plate thickness and color
Rod size and gas cylinder
Torch handle and nozzle tip
After brazing, the joint should be cooled by:
Allowing slow air cooling
Spraying cold fresh water
Wiping with dry cotton rag
Blowing compressed air jet
After work, the operator must:
Shut valves and bleed hoses
Tilt cylinders for draining
Cover torch with wet cloth
Remove regulators quickly
Before hot work, a permit must be issued by:
Ship’s responsible officer
Engine room watchkeeper
Nearest duty seaman
Fire control assistant
A fire watch is required during hot work to:
Detect and report ignition
Record hourly temperature
Adjust gas pressure levels
Clean up metal fragments
In confined space welding, proper ventilation:
Prevents gas buildup hazards
Increases welding speed
Reduces metal oxidation
Improves weld appearance
PPE for gas welding includes:
Gloves, goggles, apron
Ear muffs, belt, pads
Sandals, cap, scarf
Vest, shorts, sneakers
Oil or grease must never be used on oxygen fittings because:
It may cause explosion risk
It lowers gas pressure rate
It blocks cylinder valves
It damages the hose seal
