- Welding Safety
- Equipment Maintenance | Afrox Welding
- Welding Equipment Assembly
- Cutting Equipment Assembly
- Closing Down Equipment Safely
- Lighting Up Equipment Safely
- Testing for Leaks in Gas Equipment
- Use of Cylinders & Equipment
- Backfires & Flashbacks
- Welding Safety Precautions
- Arc Welding Safety Precautions
The equipment in a welding shop will depend on, and vary according to, the volume and scope of work, the number of welders employed and the amount of capital available. Certain items are essential while other more specialised accessories are optional. Gases may be supplied from cylinders or, in larger installations, via pipelines connected to cylinder manifolds or bulk supply systems.
For applications requiring a small cylinder welding and cutting outfit capable of being readily transported, easily moved by one person and ideal for farm work, elevated site work and jobs that are not easily accessible, the PortaPak is highly recommended.
A typical oxy-acetylene welding outfit using medium to large cylinders comprises the following:
- Cylinders of oxygen and acetylene - Always assemble with acetylene on LHS so that, should a regulator leak occur, the flame will not be directed onto the oxygen cylinder
- Pressure reducing regulators - for each cylinder
- Approved flashback arrestors
- Hoses 3m or less - fitted to each torch inlet
- 6m and longer - fitted to each regulator and each torch inlet
- Re-inforced rubber hose - blue for oxygen, red for acetylene and orange for Handigas
- Welding torch with range of nozzles
In addition to the main items listed above, the following accessories are required to complete the outfit:
- Spindle key and spanners for regulators and hose connections
- Welding goggles and spark lighter
- Welding rods and fluxes
- Cylinder trolley to accommodate the assembled outfit
Method of Assembly
- Stand both cylinders vertically, acetylene on left, and ensure they are properly supported and secured. Preferably use a cylinder trolley for this purpose. Oxygen cylinders are painted black. Acetylene cylinders are painted maroon.
- Check that the cylinder valves and all joints are free from oil and grease. Never use oil or grease on any gas equipment.
- For safety and to prevent incorrect connecting of components, oxygen fittings have right hand threads and acetylene have left hand threads.
- Before attaching regulators to cylinders, the cylinder valves should be wiped with an oil-free cloth, then rapidly open and close each cylinder valve to blow out any dust or dirt. This also ensures that empty cylinders are not being connected.
- Direct valve outlet away from people in the vicinity and keep well clear of the gas being vented.
- Ensure that regulator adjusting screws are set to zero outlet pressure i.e. turn knob anti-clockwise as far as it will go but do not force beyond stop point.
- Screw oxygen regulator into oxygen cylinder valve (right hand thread) but first note whether regulator stem/ bullnose has an "O" ring fitted. If so, the connection will seat under hand tightening of the regulator nut. If "O" ring is not fitted, then the regulator must be secured with the correct spanner.
- Do not use excessive force but make certain the joint is gas tight.
- Attach oxygen flashback arrestor to oxygen regulator (right hand thread) and tighten with appropriate spanner. Screw acetylene regulator into acetylene cylinder valve (left hand thread) and proceed as with oxygen cylinder described above.
- Attach acetylene flashback arrestor to acetylene regulator (left hand thread) and tighten with appropriate spanner.
- Connect hoses (acetylene - Red; oxygen - Blue) fitted with approved connections to outlets of flashback arrestors.
- Before connecting torch to hoses, open oxygen cylinder valve very slowly and screw in pressure adjusting screw on oxygen regulator for a short period to blow out foreign matter from hose. Close cylinder valve.
- Repeat procedure for acetylene.
- Connect torch mount arrestors to end of hoses and fit to welding torch. Ensure that torch valves are closed. Check that all connections are spanner tight - or hand tight where applicable.
- Select correct nozzle for the job and fit to torch.