Flash - instantaneous combustion of a mixture of air and vapors of flammable substances, accompanied by a brief bright glow.Stable combustion at this.Flash Point - Minimum temperature condensed matter, in which on their surface are formed a pair of flashing when a spark, flame or incandescent body.
Ability to flash at relatively low temperatures have fluid related to the category of highly flammable.Maximum flashpoint of substances in closed crucible is + 61 ° C, in the open - to + 66 ° C.Some substances can ignite spontaneously, reaching specific to their ignition temperature.
vapor pressure is possible for any flammable liquid.It grows in proportion to the temperature rise of substance.Once the temperature reaches a critical flash (maximum) index, and it becomes possible to maintain the combustion.
however offensive balance "vapor - liquid" will take some time, which is proportional to the rate of formation of vapors.Stable combustion can be achieved, reaching a certain (for each agent individually) temperature combustion as the combustion temperature is always higher than the flash point.
Direct change of temperatures at which the substance flash has some difficulties.Therefore, a flashpoint considered to be the temperature of the walls of the reaction vessels in which this outbreak there.Temperature depends directly on the conditions of heat exchange taking place inside the vessel itself, by its catalytic activity on the environment, the volume of liquid in the vessel.
Performance tests allow us to calculate allowable for transportation and storage temperature of flammable substances.Measure the temperature of the closed cup flash point, as a rule, Pensky-Martens.COC she clarified experimentally.
especially dangerous liquids can erupt at temperatures below -18 ° C in a closed crucible below - 13 ° C - in the open.Constant danger is considered to be liquid, which can flash at + 23 ° C in closed crucibles and up to + 27 ° C in the open.Temperature measurements of hazardous liquids up to + 60 ° C inclusive closed crucibles, up to + 66 ° C inclusive - in open.
temperature difference flash, ignition and combustion vary considerably, and it is individual for each substance.Flash point of diesel fuel, for example - is not more than + 70 ° C.Its combustion temperature - + 1100 ° C.The ignition temperature - from 100 ° C to 119 ° C.But the flash point of gasoline, due to the very high volatility of + 40 ° C, and sometimes less.The temperature of its ignition - +300 ° C.Indicators on gasoline, more generalized.They must be considered as average, because there are different types of gasoline (road (summer, winter), air) with significantly different characteristics and therefore different flash points, ignition, combustion.
Burning - a process accompanied by the release of large amounts of heat from the source of emission of light (illumination), perhaps at a certain temperature for each substance, and access to it of oxygen or other substances (sulfur, bromine vapor, etc.).
most dangerous are explosions, characterized by instantaneous chemical reaction with the release of enormous energy and supporting mechanical work.The fire in the explosion could spread to 3,000 meters per second.Combustion of the mixture at a rate referred to detonation.Is a consequence of the detonation shock waves often cause significant damage and accidents.
