Dispersion Control
Self-supporting steel chimneys where the gas-carrying shell is also the load-bearing structure, the cleanest interface on a project. Engineered as cantilevers to EN 1993-3-2, EN 1991-1-4 and CICIND, with the vortex-shedding response that governs slender stacks resolved before the steel is sized.
Shell Liner See It Inside
Drag the handle to compare the painted shell with the cutaway and see the liner that carries the gas inside the load-bearing structure.
In a freestanding single-flue stack the gas-carrying shell is also the structure: a cantilever fixed at its foundation that resists all wind, seismic and dead loads itself. Where the gas chemistry or temperature demands it, an internal liner (base-supported, sectional or top-hung to EN 13084-6) carries the flue gas while the structural shell stays protected, with the interspace ventilated and insulated. It is the default for most industrial sites: one foundation, no guy anchors, no carrier steelwork.
Built To Your Specification
A freestanding stack is one of the most dynamically sensitive structures an EPC will procure: tall, light and lightly damped. We identify the governing load case early, before it surprises you in detail design.
We take the required height and flue diameter from the dispersion and permit conditions, the site location and terrain, the wind climate and seismic input, and the gas temperature and chemistry.
Engineers verify the cantilever for along-wind gust response, cross-wind vortex shedding and the resulting fatigue, and seismic action (to EN 1993-3-2, EN 1991-1-4 and EN 1998-6, or CICIND) adding strakes, dampers or design-side tuning where the cross-wind response demands.
The shell, liner, base connection and access steel are fabricated and CE-marked under EN 1090 to the required execution class at our own facility, with the specified ISO 12944 coating.
Sections are delivered match-marked for efficient erection, installed and handed over with the structural, welding, NDT and coating documentation.
From the Knowledge Hub
Static along-wind gusts, dynamic cross-wind vortex shedding and seismic action: why vortex-induced vibration usually governs slender steel stacks, and how the Eurocodes and CICIND treat each.
Read the articleCapabilities
What a self-supporting stack demands as a dynamically sensitive structure.
Cross-wind
The across-wind response that governs slender stacks assessed to EN 1991-1-4 Annex E, with helical strakes, tuned dampers or design-side tuning applied where the critical wind velocity falls on everyday wind speeds.
Fatigue
Welded details at the base, manholes and flanges designed for fatigue class from the outset, because cross-wind resonance accumulates millions of stress cycles over the stack’s life.
Materials
An internal liner to EN 13084-6 and an ISO 12944 coating system matched to the corrosivity category and target durability, keeping the structural shell within temperature and corrosion limits.
In-house
Structural design, fabrication to EN 1090 and the access steel from a single source, one responsible partner from the load assessment to erection.
Reference project
Confidential potato factory operator
Axces engineered, manufactured and installed two freestanding single-flue stacks (each Ø4.5 m × 80 m, built entirely from stainless steel for the shoreline environment) to disperse process gases from a potato factory in France.
Applications
A single emission source needing a self-supporting chimney, each sized from its dispersion height and the site’s wind and seismic climate.
Power generation
Self-supporting stacks for single engine, boiler and genset exhausts, sized to the permit dispersion height.
Read moreIndustrial & EPC
Single-source process and incineration stacks delivered to EPC contractors as a combined stack-and-steel scope.
Read moreOil & gas
Stacks for fired heaters and process vents on refineries and terminals, in materials matched to the gas chemistry.
Read moreData centers
Individual backup-generator stacks on data-centre campuses, engineered to discharge clear within strict site limits.
Read moreMaritime & shore
Self-supporting stacks for shore power and harbour installations, designed for coastal corrosivity and wind.
Read moreSend us your site location and terrain, the required height and flue diameter, and the process gas data. We’ll identify the governing load case and size the stack to EN and CICIND.
