Flammenarrestern

Flammenarrestern, in English flame arresters, are safety devices designed to prevent the propagation of flame through ducts, vents, or piping that connect equipment handling flammable gases, vapors, or dust. Their primary purpose is to stop a deflagration from traveling from one side of a system to another, reducing the risk of explosions and collateral damage.

Construction and operating principle. Most flame arresters use a metal housing that contains a flame-quenching medium such as a mesh, perforated plates, or a honeycomb-like geometry. When a flame front attempts to pass through the narrow channels or cooling surfaces, heat transfer cools the gas and slows or stops the flame, while the resulting pressure drop further impedes flame propagation. Media can be made of stainless steel or other alloys chosen for the operating environment. The devices are designed to withstand specific temperatures, pressures, and contaminant loads.

Design variants. Flame arresters are commonly categorized by location and flow path into end-of-line arresters (installed at the outlet of a vessel or duct) and inline or in-pipe arresters (installed within a duct or piping run). Other distinctions include the type of quenching media and the degree of resistance to corrosion, dust, or moisture.

Applications and considerations. They are used in storage tanks, chemical processing plants, painting and coating operations, mining equipment, and marine and fire-protection systems. Selection depends on the flammable substance, ignition source risk, allowable pressure drop, temperature and corrosion resistance, and adherence to applicable standards and codes.

Standards and maintenance. Flame arresters are subject to regional explosion-protection standards and manufacturer specifications. Compliance may involve approvals from bodies such as BSI/EN, ATEX, UL/FM, or other national certifications. Regular inspection and replacement of degraded media are essential to maintain effectiveness.