Welded stainless duct and fittings
Corrosion-Resistant Ductwork
Fully welded stainless duct and fittings for corrosion resistance, washdown, cleanability, or exposed stainless construction.
- Best for duct runs that need stainless material, TIG welded seams, passivated welds, or visible-finish handling.
- Use 304 for general stainless service; use 316L when corrosion exposure, washdown, chemical, or coastal conditions require it.
- Confirm grade, gauge, finish, visible faces, connection style, and field-fit dimensions before release.
Material304 or 316L SS
WeldingTIG welded
FinishMill or #4 brushed
Construction Standard
| Application | Custom welded stainless ductwork and fittings for exhaust, process, washdown, food-service, cleanable, corrosive, or exposed applications. |
| Material grade | 304 stainless steel is typical; 316L stainless steel is available when corrosion resistance or project specifications require it. |
| Gauge range | Welded stainless duct is available from 20 gauge through 10 gauge, supplied as quoted based on size, application, and project requirements. |
| Welding process | Stainless duct is TIG welded and passivated unless a different weld process, finish, or treatment is specifically quoted. |
| Straight sections | Produced in 5'-0" nominal lengths, less end flange allowance. Shorter sections and coordinated field-fit pieces can be fabricated when required. |
| End preparation | 1/2" flanges are standard. Angle rings, custom flange types, special bolt patterns, collars, and companion flange details can be fabricated as shown or quoted. |
| Finish handling | Mill finish and #4 brushed finish are available. Confirm finish, grain direction, protective handling, and visible-face requirements before release. |
| Quality check | Weld seams receive visual inspection before release. Leak testing, pressure testing, NDT, or certified inspection are by others unless quoted. |
Build Quality
Made to specBuilt to released grade, gauge, finish, and connection details.
Built tough304 or 316L stainless for cleanable or corrosive service.
Quality checkedTIG welds are visually inspected and passivated when quoted.
Finish awareVisible faces, grain direction, and handling planned before release.
Fabrication Capabilities
| Duct sections | Rectangular and round straight duct, field-fit pieces, risers, drops, and custom lengths. |
| Fittings | Rectangular and round elbows, radius bends, offsets, tapers, reducers, transitions, branches, and tees. |
| Connections | 1/2" flanged duct systems are typical for fully welded connections. Equipment transitions, collars, curb adapters, wall/shaft connections, and roof penetration fittings are available. |
| Field-fit work | Short sections, piece-marked runs, and coordinated connection faces. |
| Shop details | Tabs, brackets, companion flanges, reinforcement, and special flange details when requested. |
| Release support | Built from released dimensions with stainless grade, finish direction, visible faces, connection details, and passivation expectations confirmed before fabrication. |
Material Notes
304 or 316L304 stainless is common for general service; 316L is available for higher corrosion, washdown, chemical, or coastal exposure.
Passivated weldsStainless duct is TIG welded and passivated to clean weld heat tint and support corrosion resistance at fabricated seams.
Finish handlingMill finish or #4 brushed finish can be supplied. Visible faces, grain direction, and handling expectations should be identified before release.
Best fitChoose welded stainless when the project needs stainless material plus continuous welded seams; use stainless lock seam for lighter mechanical duct where welded seams are not required.
Connection Options
Couplings
Raw endsRaw ends with couplers for screw assembly.
1/2" flange
Field welded1/2" flanges for field welded assembly.
TDC / Ductmate
Bolted sealBolted connections with butyl sealant.
Rings / flanges
Custom patternVanstoned or welded angle rings, frames, and bolt flanges.
Optional Accessories
AccessStainless doors, cleanout openings, inspection panels, and drain fittings.
FinishMill finish, #4 brushed finish, visible-face handling, grain direction, and protective film needs.
ConnectionsFlexible connectors, companion flanges, tabs, brackets, angle rings, and piece marks.
Custom detailsCustom bolt patterns, stainless hardware, reinforcement, liner/insulation, or special finish requirements.
Required for Quote / Release
- 304 or 316L grade, gauge, duct size, quantity, and required nominal or field-fit lengths.
- Approved drawing, sketch, or verified field dimensions with airflow/orientation noted.
- Flange type, bolt pattern, companion flange needs, and connection face details.
- Mill or #4 finish, grain direction, visible faces, and handling requirements.
- Piece marks, access openings, reinforcement, pressure class, liner/insulation needs, and any testing requirements.
Not Included Unless Quoted
- Installation, field welding, hoisting, rigging, roofing, or roof penetration work.
- Engineering, permits, inspections, balancing, cleaning beyond quoted passivation, fire wrap, fire-rated enclosure, or listed-system certification.
- Leak testing, pressure testing, gaskets, sealant, stainless hardware, companion flanges, or rework from changed release dimensions unless quoted.
Scope & Responsibility
Code note: Stainless duct systems may be governed by mechanical code, local code, project specifications, material compatibility requirements, and AHJ requirements. Empire fabricates duct and fittings to released dimensions and quoted scope; final system design, material selection, installation method, field welding, sealant/gasket requirements, clearances, and acceptance remain the responsibility of others unless expressly included.
Ready to Quote?
Let's get your duct package moving.
Send drawings, sketches, photos, or field measurements. Empire is ready to go to work for you.
quotes@empiremetalproducts.com
602-424-9980