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POYYARA
CONSULTANTS
OXY FUEL FLAME CUTTING
POYYARA
CONSULTANTS
OXY FUEL FLAME CUTTING
•Cutting Gas
• Oxygen
•Fuel Gas
• Acetylene
• LPG – Liquid Petroleum Gas
POYYARA
CONSULTANTS
OXY FUEL FLAME 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
POYYARA
CONSULTANTS
OXY FUEL FLAME 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
POYYARA
CONSULTANTS
OXY FUEL FLAME 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
POYYARA
CONSULTANTS
OXY FUEL FLAME 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%
POYYARA
CONSULTANTS
OXY FUEL FLAME 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
POYYARA
CONSULTANTS
OXY FUEL FLAME 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 – 5 kg
POYYARA
CONSULTANTS
OXY FUEL FLAME CUTTING
Type Of Oxy - Fuel Gas Flames
Carburising Flame
Neutral Flame
Oxidising Flame
POYYARA
CONSULTANTS
OXY FUEL FLAME 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)
POYYARA
CONSULTANTS
OXY FUEL FLAME 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%
POYYARA
CONSULTANTS
OXY FUEL FLAME CUTTING
Cutting Process
Typical Flame Cutting Nozzle
POYYARA
CONSULTANTS
OXY FUEL FLAME CUTTING
POYYARA
CONSULTANTS
OXY FUEL FLAME CUTTING
• Cutting Blow Pipe / Torch
POYYARA
CONSULTANTS
OXY FUEL FLAME CUTTING
ESAB make Cutogen Nozzles for Acetylene
Material ThicknessSize 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.
POYYARA
CONSULTANTS
OXY FUEL FLAME 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
POYYARA
CONSULTANTS
OXY FUEL FLAME 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
POYYARA
CONSULTANTS
OXY FUEL FLAME 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
POYYARA
CONSULTANTS
OXY FUEL FLAME CUTTING
• Accessories- Gas Cylinders( O2 & Fuel Gas) with Pressure Regulators.- Pair of Hose Pipe Connections- Cutting Torch - Cutting Nozzle
POYYARA
CONSULTANTS
OXY FUEL FLAME CUTTING
• Accessories – O2 Cylinder- Oxygen Cylinder Neck – Right Hand Threaded
- All connections to O2 Gas Regulator, Hose Nipples , Torch Nipples- Right Hand Threaded
POYYARA
CONSULTANTS
OXY FUEL FLAME 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
POYYARA
CONSULTANTS
OXY FUEL FLAME 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
POYYARA
CONSULTANTS
OXY FUEL FLAME 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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