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GAS CUTTING.ppt It contain basic information about gas cutting process
- 1. POYYARA CONSULTANTS OXY FUELFLAME CUTTING
- 2. POYYARA CONSULTANTS OXY FUELFLAME CUTTING •Cutting Gas • Oxygen •Fuel Gas • Acetylene • LPG – Liquid Petroleum Gas
- 3. POYYARA CONSULTANTS OXY FUELFLAME CUTTING •Oxygen Gas •Extracted From - Atmosphere, Fractionalization Of Air - Water, Electrolysis •Stored In Cylinders - At High Pressure – 1800 psi - Cylinder Colour – Black - Quantity in Volume 7.3 M3
- 4. POYYARA CONSULTANTS OXY FUELFLAME CUTTING •Acetylene – Fuel Gas • Produced by the reaction of - Calcium Carbide with Water - Cac2 + 2H2O = C2H2 + Ca(OH)2 • Molecular Weight – 26, Lighter Than Air
- 5. POYYARA CONSULTANTS OXY FUELFLAME CUTTING •Acetylene – Fuel Gas • Unsafe to Store Free Acetylene above 0.2 Kgs/cm2 – Decompose With Explosion • Acetylene Dissolves in Acetone @ 25:1 (V/V) at 1 Atmospheric Pressure • Solubility increases in multiples of 25 for every increase in Pressure by 1 atmospheric
- 6. POYYARA CONSULTANTS OXY FUELFLAME CUTTING •Acetylene – Fuel Gas • Stored In cylinders with Porous Mass - dissolved in Acetone - Maximum Pressure of DA – 20 Kgs/cm2 - Quantity of DA Gas in Full cylinder By volume 6 – 7 M3 - Cost of Gas Appx. Rs:100/- per M3 - Purity of Gas Not Less Than 96%
- 7. POYYARA CONSULTANTS OXY FUELFLAME CUTTING •Acetylene – Fuel Gas • Cylinder Colour- Maroon • Flat Bottom Cylinders – To be Kept Vertical While in Use • Internal Bore of Cylinder neck - Left Hand Threaded
- 8. POYYARA CONSULTANTS OXY FUELFLAME CUTTING • LPG – Fuel Gas • Produced in refineries • Stored In cylinders - Liquid + vapor stage - At Low Pressure - Cylinder Colour- Red - Flat Bottom Cylinder - Quantity in Weight – 14 kg
- 9. POYYARA CONSULTANTS OXY FUELFLAME CUTTING Type Of Oxy - Fuel Gas Flames Carburising Flame Neutral Flame Oxidising Flame
- 10. POYYARA CONSULTANTS OXY FUELFLAME CUTTING Cutting Process • Feasible Only On Plain Carbon Steels & Low Alloy Steels • Process is by Conversion of iron to iron oxide • Steel Locally Heated to Kindling Temperature (800˚C) by Oxy Fuel Preheating Flame. • A jet of oxygen is then impinged on this preheated hot iron. • Iron instantaneously converted in to black iron oxide. • Exothermic Reaction • 2Fe + O2 = FeO + Heat (270 kJ), • 3Fe + 2O2 = Fe3O4 + Heat (1100kJ)
- 11. POYYARA CONSULTANTS OXY FUELFLAME CUTTING Cutting Process • Kinetic energy of Oxygen jet drives all non metallic iron oxide . • Heat Generated in exothermic reaction is self sustaining for preheating the metal ahead to cut • When flame with a jet of oxygen at the centre moves close to the material, the process is continues by separating the material along the path of oxygen jet • Purity of oxygen required for cutting - 99.5%
- 12. POYYARA CONSULTANTS OXY FUELFLAME CUTTING Cutting Process Typical Flame Cutting Nozzle
- 13. POYYARA CONSULTANTS OXY FUELFLAME CUTTING
- 14. POYYARA CONSULTANTS OXY FUELFLAME CUTTING • Cutting Blow Pipe / Torch
- 15. POYYARA CONSULTANTS OXY FUELFLAME CUTTING ESAB make Cutogen Nozzles for Acetylene Material Thickness Size of Nozzle Cutting Oxygen Pressure mm inch Kg/cm2 lb./in2 6 1/4 1/32-A-8 1.4 20 12 1/2 3/64-A-12 2.0 30 25 1 1/16-A-16 2.5 35 50 2 1/16-A-16 3.2 45 75 3 1/16-A-16 3.5 50 100 4 1/16-A-16 4.2 60 150 6 5/64-A-20 4.5 65 200 8 3/32-A-24 4.9 70 250 10 7/64-A-28 5.3 75 300 12 1/8-A-32 5.3 75 Acetylene pr. should be set in all cases at 0.14 kg/cm2 , 2 lb./in2 .
- 16. POYYARA CONSULTANTS OXY FUELFLAME CUTTING ESAB make LPG / NG nozzle Thickness Nozzle Size Operating Pressure Oxygen L.P.G/ N.G. mm Kg/cm2 Kg/cm2 6 P-8 2.1 0.2 13 P-12 2.1 0.2 25 P-16 2.8 0.2 50 P-16 3.2 0.3 75 P-16 3.5 0.3 100 P-20 3.5 0.3
- 17. POYYARA CONSULTANTS OXY FUELFLAME CUTTING • Cutting Process Using • LPG as Fuel Gas - Comparatively Poor Cutting Edge / Surface. - Maximum Cutting Thickness – 100 mm - Cutting Nozzle –Two Piece Construction - Cutting Parameters (Pressure - O2 & LPG & Cutting Speed) different from Oxy acetylene
- 18. POYYARA CONSULTANTS OXY FUELFLAME CUTTING • Cutting Process Using • Acetylene as Fuel Gas - Comparatively Good / Smooth Cutting Edge / Surface. - Maximum Cutting Thickness – 300 mm - Cutting Nozzle –Single Piece Construction - Cutting Parameters (Pressure - O2 & C2H2 & Cutting Speed) different from Oxy + LPG
- 19. POYYARA CONSULTANTS OXY FUELFLAME CUTTING • Accessories - Gas Cylinders( O2 & Fuel Gas) with Pressure Regulators. - Pair of Hose Pipe Connections - Cutting Torch - Cutting Nozzle
- 20. POYYARA CONSULTANTS OXY FUELFLAME CUTTING • Accessories – O2 Cylinder - Oxygen Cylinder Neck – Right Hand Threaded - All connections to O2 Gas Regulator, Hose Nipples , Torch Nipples- Right Hand Threaded
- 21. POYYARA CONSULTANTS OXY FUELFLAME CUTTING • Accessories – C2 H2 - Acetylene Cylinder Neck – Left Hand Threaded With A Notch on Hexagonal Nut - All connections to Acetylene Gas Regulator, Hose Nipples , Torch Nipples- Left Hand Threaded
- 22. POYYARA CONSULTANTS OXY FUELFLAME CUTTING • Difference in Appearance of Accessories - Oxygen Cylinder – Black - Oxygen Cylinders may or may not be flat bottom - Oxygen Gas Regulator, Hose, knob on Torch- Black - Hexagonal Nipple Connections of O2 Gas Without Any Notch – Plain
- 23. POYYARA CONSULTANTS OXY FUELFLAME CUTTING • Difference in Appearance of Accessories - Acetylene Cylinder – Maroon - Acetylene Cylinder- Flat Bottom - Acetylene Gas Regulator, Hose , Knob on Torch – Maroon - Hexagonal Nipple Connections of Acetylene Gas - With Notch on Corners
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