SAFE WORK PRACTICES
GAS WELDING & CUTTING – SETUP, REGULATOR SETUP, LEAK TEST Page 1 of 3
*This information does not take precedence over OH&S. All employees should be familiar with the Saskatchewan Employment Act
and the OH&S Regulations.
Equipment Connection:
1.
Oxygen cylinders have right turning valves and connections.
Fuel cylinders have left turning valves and connections.
2.
“Crack” open cylinder valves slightly and then close immediately
(except hydrogen gas). This blows out dust and grit that could
restrict the gas flow or damage the regulator.
3.
Attach the oxygen and fuel gas regulators to their cylinders (see
“Regulator Setup”). Tighten nuts with a proper wrench. Never
force poor fitting connections.
4.
Install non-return valves and flashback arrestors on the torch
and regulator end of the hoses (see “Leak Test”).
5.
Connect the green (black) hose to the oxygen regulator and the red hose to the fuel gas
regulator.
6.
Connect torch green hose to the oxygen inlet and red hose to the fuel gas inlet. Finger
tighten hose nuts before using wrench. The wrench may damage unprotected threads.
7.
Keep cylinders upright in a cylinder trolley for firm support.
8.
Examine hoses before use for signs of damage. Secure connections with clips or crimps.
Check connections and non return valves regularly.
9.
Stand to one side of regulator face when opening the cylinder valve outlet. Open cylinder
valves slowly.
10. Open cylinder valves only with approved keys or hand wheels. Do not use excessive force
to open or close cylinder valve.
11. Select the proper welding head or mixer, tip or cutting nozzle from the charts supplied by
the manufacturer and screw it firmly into the torch.
12. Use table tops made of fire brick or steel plate. Regular brick may pop or explode from
heat. Keep flames and hot metal off concrete.
13. Leave the valve wrench/handle on the fuel gas cylinder whenever the valves are open.
This permits emergency shut-off of the gas.
SAFE WORK PRACTICES
GAS WELDING & CUTTING – SETUP, REGULATOR SETUP, LEAK TEST Page 2 of 3
14. DON’T:
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connect a hose longer than needed – keep hose from becoming kinked or tangled
use tape to repair a leaky hose
have oil or grease on any welding or cutting equipment – this may cause an explosion
Regulator Setup:
1.
Make sure the regulator inlet threads match the cylinder valve outlet threads. Connect the
regulator to the cylinder’s outlet valve.
2.
Release the pressure adjusting screw on the regulator by turning counter clockwise. Open
the downstream line to the air to drain the regulator gas.
3.
Open the cylinder vale slightly to let the needle in the cylinder contents gauge move up
slowly. On an oxygen cylinder, open cylinder valve fully; on an acetylene cylinder turn
valve only 1 ½ turns.
4.
When closing down, shut the cylinder valve open torch
valve before slackening the pressure adjusting screw.
5.
If a regulator shows excessive pressure “creep” replace
immediately. “Creeping” of a regulator is shown by a
gradual increase in pressure after the torch valves are
closed. To check for “creep”, close the welding or cutting
torch valves while the regulator is open and check for
increase in indicated pressure. Refer to manufacturer’s
operating manual.
6.
Make sure to:
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

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7.
stand to one side and away from regulator gauge faces when opening cylinder valves
leave key wrenches on cylinders in use so they can be closed quickly
ensure connections between the regulators and cylinder valves are tight
check accuracy of regulator pressure gauge at least yearly
DON’T:



use pipe wrenches or pliers for attaching regulators to cylinders – use wrench of proper
size
open cylinder valve until the regulator is drained of gas and the pressure adjusting
screw on the regulator is fully released
thaw a frozen regulator with a flame – use warm water
SAFE WORK PRACTICES
GAS WELDING & CUTTING – SETUP, REGULATOR SETUP, LEAK TEST Page 3 of 3
DON’T (continued)
 interchange regulators for a gas with similar equipment intended for use with other
gases
 use oil or grease as a lubricant for tight threads – any oil or grease on a regulator or
fitting may cause an explosion
 release the pressure adjusting screw when there is pressure in the hose and the hose
torch valve is closed – the valve diaphragm will be damaged
Leak Testing Oxygen Connections:
1. Make sure torch oxygen valve is closed.
2. Turn pressure adjusting screw on the oxygen regulator to normal working pressure.
3. Stand to one side and slowly open the oxygen cylinder valve. Watch the pressure rise
gradually on the cylinder contents gauge. Sudden opening of the cylinder valve may
damage the regulator or lead to a fire.
4. Set regulator to pressure recommended by supplier.
5. Check regulator for an increase in the reading “creeping” on the outlet pressure gauge. If it
creeps – close the cylinder valve. Check for a drop in pressure on regulator gauges. Any
drop indicates a lead between the cylinder valve and the torch valve.
6. Check for leaks at the top of the cylinder.
7. Once all leaks have been corrected, reopen the cylinder valve slowly.
Leak Testing Fuel Connections:
8. Repeat steps 1 to 7 except, in step 2, set pressure adjusting screw on the acetylene
regulator pressure to produce a pressure of 69kPa (10 psig).