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Oxyacetylene-welding-tipsmay be the process of choice if suitable.SOLUTIONS with Effective, Practical Advice
Oxyacetylene-welding-tips But even then... are you ready to explain it -- to young people who newer saw it in action? They may think that only laser (!?) is the way to go... Can you present it concisely and completely, with all the Oxyacetylene-welding-tips that you know practically? Oxyacetylene-welding has so many unique advantages that, whenever it is suitable, no other process can easily compete with it. This page on Oxyacetylene-welding-tips refers to a manual process where the heat of an Oxyacetylene flame from a torch, melts progressively the edges of metal parts with or without filler metal. Molten materials flow together and solidify in the welded joint without application of pressure. Oxyacetylene-welding (OAW) is a special case of Oxyfuel Gas Welding (OFW). However, other gases that were used in the past (hydrogen, propane, natural and manufactured gases) have now only limited use and only for particular cases where lower temperature is sufficient.
Some of the following items were already pointed out in our other page on Gas Welding Processes, while additional Oxyacetylene-welding-tips are listed here.
The best Oxyacetylene-welding-tips point to the many advantages:
The Oxyacetylene-welding-tips limitations include:
As Oxyacetylene-welding is probably available in every shop, the conscious welder should examine any new job to determine if the advantages of the process make it the natural and economic solution.
Equipment Oxyacetylene-welding-tips for Gases should explain that they are normally stored under pressure in special gas cylinders regulated by appointed authorities and subject to periodic controls. Oxygen cylinders of various capacities are available. The most frequently used has a capacity of 6.9 m3 or 224 standard cubic feet (scf). When full, its pressure is around 15 MPa (1 Mega Pascal = 1 Newton per mm2) or about 2200 psi. Acetylene cylinders are special. Acetylene becomes unstable and can explode under a slight shock when its pressure is above 203 kPa (1 kilo Pascal = 1000 Newton per m2) or about 29.4 psi. Therefore safety regulations prohibit its use at a pressure of 105 kPa (15 psi) or higher. Commercially available cylinders for acetylene are filled with a porous material containing liquid acetone. Acetylene is dissolved in liquid acetone and then it can be stored under pressure of 1.7 MPa (250 psi) without danger. Capacity of a normal acetylene cylinder is about 7.8 m3 or 275 scf. A pair of pressure regulators is installed on top of the cylinders when in use. One is the cylinder pressure gage that shows at any time the actual pressure in the cylinder. The other one permits to regulate the low delivery pressure and shows it to the welder. Two types of regulators are in use. Single stage are simpler and cheaper, but their delivery pressure is not really uniform. Two stage regulators are more expensive but guarantee an almost constant delivery pressure until the cylinder has no more gas to supply. Note that regulators are made for a specific gas and are not interchangeable. The use of oil or grease in the oxygen line fittings is prohibited because of the danger of self igniting fire. Color coded flexible hoses deliver separately the gases to the torch where they are admitted to the mixer chamber in the right proportion for the desired flame, according to the work at hand (slightly reducing = with excess acetylene, or neutral, or slightly oxidizing = with excess oxygen). Welders are instructed to evaluate the type of the flame by examining the aspect of the white cone, its hottest part.
Oxygen hose connections are threaded right-handed. Acetylene hose connections are threaded left-handed and are grooved or marked accordingly. This helps prevent accidentally switching oxygen and acetylene hoses. Torch handles are small, medium sized or heavy duty, depending on the amount of gas flow they permit, normally correlated to the mass or thickness of the parts to be welded. Interchangeable tips of proper size must be selected according to the type of work on hand. No universal standardization of types and sizes is in place so that one should follow manufacturers' recommendations. Torches are fitted with flame traps or flashback arrestors, designed to avoid that the flame run back to torch or cylinders, causing damage and injuries.
Welding Oxyacetylene-welding-tips show that welding can be performed either with the torch tip pointing in the direction of the weld to do (forehand) or in that of the weld just done (backhand). Each technique has its own specific advantages but it is mostly personal preference. Thin sheet and tubes are welded successfully with Oxyacetylene-welding, with proper edge preparation and fixturing depending on thickness and joint type. Other Oxyacetylene-welding-tips insist that Cleanliness of the material to be welded is a condition for successful Oxyacetylene-welding. All contaminating materials like rust, scale, dirt, oil, grease, paint or slag must be thoroughly removed from the area. Low carbon steel is the material mostly welded by this process, but with the use of proper fluxes, other materials like aluminum, brasses, copper, cast iron, nickel alloys and stainless steels can be Oxyacetylene welded successfully. Flux remainders however should be flushed away thoroughly to prevent future corrosion. This is the main reason that leads to prefer other processes, when available, that do not need fluxes, instead of Oxyacetylene-welding. Mild steel Oxyacetylene weldments, on the contrary, present the additional advantage of not needing any finishing treatment unless prescribed by design (filing, grinding, peening etc.). Welders should always wear darkened goggles when observing welding in progression to protect their eyes, and use gloves and protective clothing as explained in Safety Oxyacetylene-welding-tips. Welders must be acquainted with safety provisions, instructed and supervised accordingly. Many good reviews of safety Oxyacetylene-welding-tips are available:
A nice recap power point presentation of Oxyacetylene-welding-tips is downloadable from AWS at A short review of Equipment including Oxyacetylene-welding-tips is available from TWI at In conclusion Oxyacetylene-welding-tips show that this is still one of the most useful processes capable of providing economical and successful solutions in many cases of production or repair. It is the first process to be considered when planning any new job.
An Article on Safety with Oxy-acetylene flames was published (2) in Issue 109 of Practical Welding Letter No. 109 for September 2012. To receive this publication each month at no cost, please subscribe.
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Despite its long history that makes it look old fashioned, Oxyacetylene-welding is still the process of choice for many common repairs or fabrications, especially for thin materials.
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