Flame arrestor with reflection suppressor

A process for arresting a flame in a pipe having a localized restriction therein, said pipe carrying a flammable but deflagratable gas, said process comprising the steps of:

• (a) centrally positioning a reflection suppressor in one selected opposite end region of a detonation flame arrestor, said reflection suppressor having—
• side wall portions that extend between a base portion and an apex portion thereof,
• a length that is shorter than the distance between an orifice and a matrix of elements in a selected one of said opposite end portions,
• a cross-sectional area along said length between said base portion and said apex portion that generally declines with increasing distance from said base portion, and
• said base portion having a cross-sectional area that is less than the cross sectional area of said selected one opposite end region;
• and
• (b) connecting each of said orifices across said pipe so that said detonation flame arrestor is located at a situs in said pipe that is between said restriction therein and a region thereof where ignition of said flammable gas could occur;
• said flame arrestor being oriented so that said reflection suppressor therein has said base thereof facing in the pipe direction of said restriction,
• whereby, when ignition occurs, and an advancing flame front with an associated pressure wave occurs in said region and propagates through said pipe, said flame front is suppressed upon reaching and entering said flame arrestor, but said pressure wave passes through said flame arrestor and around said reflection suppressor and travels in said pipe to said restriction, and a reflection pressure wave is produced at said restriction which propagates back through said pipe to said detonation flame arrestor, strikes said reflection suppressor, and is attenuated thereby.