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A set of MAPP and oxygen cylinders is used for oxy-fuel welding and cutting.. MAPP gas was a trademarked name, belonging to The Linde Group, a division of the former global chemical giant Union Carbide, for a fuel gas based on a stabilized mixture of methylacetylene (propyne), propadiene and propane.
Assuming initial atmospheric conditions (1 bar and 20 °C), the following table [1] lists the flame temperature for various fuels under constant pressure conditions. The temperatures mentioned here are for a stoichiometric fuel-oxidizer mixture (i.e. equivalence ratio φ = 1).
MAPP gas can be used at much higher pressures than acetylene, sometimes up to 40 or 50 psi in high-volume oxy-fuel cutting torches which can cut up to 12-inch-thick (300 mm) steel. Other welding gases that develop comparable temperatures need special procedures for safe shipping and handling.
Limits vary with temperature and pressure, but are normally expressed in terms of volume percentage at 25 °C and atmospheric pressure. These limits are relevant both in producing and optimising explosion or combustion, as in an engine, or to preventing it, as in uncontrolled explosions of build-ups of combustible gas or dust.
A combustible material is a material that can burn (i.e., sustain a flame) in air under certain conditions. A material is flammable if it ignites easily at ambient temperatures. In other words, a combustible material ignites with some effort and a flammable material catches fire immediately on exposure to flame.
The justification for using oxy-fuel is to produce a CO 2 rich flue gas ready for sequestration. Oxy-fuel combustion has significant advantages over traditional air-fired plants. Among these are: The mass and volume of the flue gas are reduced by approximately 75%. Because the flue gas volume is reduced, less heat is lost in the flue gas.
Temperature of atmosphere links to adiabatic flame temperature (i.e., heat will transfer to a cooler atmosphere more quickly) How stoichiometric the combustion process is (a 1:1 stoichiometricity) assuming no dissociation will have the highest flame temperature; excess air/oxygen will lower it as will lack of air/oxygen
At standard temperature and pressure, oxyhydrogen can burn when it is between about 4% and 95% hydrogen by volume. [5] [4] When ignited, the gas mixture converts to water vapor and releases energy, which sustains the reaction: 241.8 kJ of energy for every mole of H 2 burned.