Presentation on theme: "Unit 4: Oxyacetylene Welding and Cutting in Agriculture"— Presentation transcript:
1Unit 4: Oxyacetylene Welding and Cutting in Agriculture
2Objectives4.1 Define terminology 4.2 Describe the oxyacetylene welding and cutting processes in agriculture 4.3 Distinguish parts and functions of oxyacetylene welding and cutting equipment and supplies 4.4 Describe safe practices in oxyacetylene welding and cutting 4.5 Describe the process of using oxyacetylene welding and cutting equipment
34.1 Define terminology1. Bleeding the lines – moving gas pressure from all lines and equipment, as with oxyacetylene welding systems2. Brazing – the process of joining metal with a filler rod that melts at a temperature below the metal being joined3. Carbonizing flame – a flame with excess acetylene; adjustment is needed to achieve a neutral flame4. Cutting tip – a special tip used in cutting metal with gas systems such as oxyacetylene5. Filler rod – a long, thin metal rod used in welding to add to or fill joints when welding or brazing
44.1 Terms Cont.6. Flammable – the quality of a substance that is capable of burning7. Fusion – the process of joining by melting, as in fusion welding8. Gauge – a device used to measure certain substances such as pressure in an oxyacetylene welding/cutting system9. Neutral flame – an oxyacetylene flame with a balance of oxygen and acetylene10. Oxidizing flame – an oxyacetylene flame with an excess of oxygen; adjustment is needed to achieve a neutral flame
54.1 Terms Cont.11. Regulator – a device that controls the flow amount of a liquid or gas; with oxyacetylene welding systems, regulators control the flow of oxygen and acetylene12. Tip – the part of a welding or cutting torch with holes to release fuel for combustion13. Tip cleaner – small, round rod-like devices that remove dirt from the holes in welding and cutting torch tips14. Torch – the assembly in an oxyacetylene system that mixes oxygen and acetylene to provide the desired flame15. Valve – a device that controls the flow of gas in an oxyacetylene system
64.2 Describe the oxyacetylene welding and cutting processes in agriculture
7Uses of Oxy-fuel Cutting and Welding What are some examples of cutting torch uses on the farm?Have you ever used a gas welder at home?
8Relate welding and cutting processes to different kinds of metal
94.3 Distinguish parts and functions of oxyacetylene welding and cutting equipment and supplies
21Identify, compare, and select filler rods by type and by metal to be welded
224.4 Describe safe practices in oxyacetylene welding and cutting
23Identify fire protection equipment Objective 4: Describe fire prevention and personal protection in welding and Identify and properly use personal protection equipment in oxy-fuel cutting and weldingIdentify fire protection equipment
24List the practices to follow to prevent accidents Make sure you have all PPE on at all times!!This includes your shade 4 glasses at all times while looking at the flame.Make sure that you always shut off the acetylene valve first then the oxygen.Do not point the torch directly into the lighter. Never use a match or cigarette lighter to light the torch.
25Identify proper ways of handling hot metal Once you have made a weld that you want looked at use a pair of pliers to carry the hot metal. Take the metal to the sink and cool it off. Then you can bring it to me for a grade. Using this method will save our gloves in the long run!!
26Identify practices to follow in safely storing and using compressed gas Acetylene CylindersAcetone - absorbs acetylene under pressureConsumption rate = 1/7 content per hourFusible plug FTemperature has an extreme affect on pressureLet stand upright at least 20 minutes before usingProtected valve or cylinder capStored away from oxygen and combustibles5’ high wall1/2 hour fire rating
27Identify practices to follow in safely storing and using compressed gas Oxygen CylindersPressure is about 2200 psi at 700 FHydrostatic tested to 3300 psiForged from a single piece of steel - no weldingMinimum of 1/4” thicknessAnnealed periodicallyStored away from combustibles5’ high wall1/2 hour fire rating
28Acetylene safety Precautions Never call acetylene “gas”Extremely explosive with air or oxygenLeave wrench on tank
29Oxygen Safety Precautions Never call oxygen “Air”Never allow oxygen to come in contact with oil, grease, or other petroleum basesNever use oxygen for compressed airNever move cylinders without capsAlways secure cylinders
304.5 Describe the process of using oxyacetylene welding and cutting equipment
31Lighting Procedure1. Place goggles or safety glasses and face shield on your forehead.Must be shade 4 lenses.2. Be sure regulator adjusting screws are turned out.The screw should turn freely.
32Lighting Procedure3. Standing to one side, not directly in front of the regulator, open the oxygen cylinder valve slowly, then open it all the way.Set the regulator at the correct working pressure.Open the oxygen blowpipe valve and fine tune the operating pressure.Cutting- 40 psiWelding psiClose the oxygen blowpipe valve.
33Lighting Procedure Only open the tank valve ½ to ¾ of a turn. 4. Standing to one side, not directly in front of the regulator, open the acetylene cylinder valve slowly.Only open the tank valve ½ to ¾ of a turn.Set the regulator at the correct working pressure.Open the acetylene blowpipe valve and fine tune the operating pressure.Cutting psiWelding- 5-7 psiClose the acetylene blowpipe valve.
34Lighting Procedure5. Put on gloves, and lower goggles or face shield over eyes.
35Lighting Procedure6. With the friction lighter in the left hand at the tip of the blowpipe, and the blowpipe in the right hand, open acetylene blowpipe valve with the right thumb and forefinger one-eighth to one-quarter turn.Strike the friction lighter and adjust the acetylene level.
36Lighting Procedure7. Adjust the acetylene by opening the blowpipe valve until the flame leaves the tip about ¼ inch.Close the valve very slowly until the flame is pulled back to the end of the tip.Open the valve slowly again, stopping just before the flame leaves the tip.This is the proper adjustment for most welding.
37Lighting Procedure8. Open oxygen blowpipe valve and set the desired flame type.
38The correct shutting down procedure is as follows.
39Shut Down Procedures 1. Close the acetylene blowpipe valve. 2. Close the oxygen blowpipe valve.3. Close acetylene tank valve.4. Close oxygen tank valve.
40Shut Down Procedures5. Open the acetylene blowpipe valve to drain the hose and release all pressure from the hose and regulator.6. Turn out the pressure-adjusting screw on the acetylene pressure regulator by turning it counterclockwise.
41Shut Down Procedures 7. Close the acetylene blowpipe valve. 8. Open the oxygen blowpipe valve to drain the hose and release all pressure from the hose and regulator.
42Shut Down Procedures9. Turn out the pressure-adjusting screw on the oxygen pressure regulator by turning it counterclockwise.10. Close the oxygen blowpipe valve.11. Wrap up hoses and put welding accessories in their proper place.
43Fuel Gas Welding Techniques setting the proper flamepreparing the pieces to be weldedknowing the common types of weldsholding and using the blowpipe and rodcompleting the different types of welds.
44Three types of oxyacetylene welding flames. 1. The neutral flame is usually used for welding. A neutral flame will produce a smooth, shiny bead of the best quality.
45Three types of oxyacetylene welding flames. 2. The oxidizing flame is caused by an excessive amount of oxygen, which produces a short white inner cone and a short envelope flame.An oxidizing flame will produce sparks that shower the weld area with droplets of metal and slag, leaving the weld zone weak and porous.
46Three types of oxyacetylene welding flames. 1. The carburizing flame is caused by an excessive amount of acetylene and has a long, bluish outer flame.A carburizing flame will cause the puddle to foam and boil, leaving a brittle, porous, and scaly weld area.The carburizing flame is used for hard-surfacing.
49ReviewDescribe the oxyacetylene welding and cutting processes in agricultureDistinguish parts and functions of oxyacetylene welding and cutting equipment and suppliesDescribe safe practices in oxyacetylene welding and cuttingDescribe the process of using oxyacetylene welding and cutting equipment