Airflow Geometry
Rectangular, tapered, offset and adapter sections are built around your airflow path, equipment envelope and installation access.
HVAC & Airflow Fabrication
Custom Sheet
Custom Sheet
Metal Ducts &
Plenums
Custom galvanized, stainless and aluminum duct sections, HVAC plenum boxes, transition ducts, filter housings and equipment ventilation assemblies built to OEM drawings. We control flanges, access panels, seams, reinforcement and packout so airflow hardware arrives ready for installation.
✓ Plenums, ducts and transitions
✓ Galvanized and stainless options
✓ Access panels and gasket lands
RFQ program quantity
RFQ
Example Order Size
RFQ
Configuration Count
Drawing
Referenced Requirements
Plan
Inspection Scope
01 / What We Fabricate
The Duct Structure Behind Reliable Airflow
Ducts and plenums need more than folded sheet metal. They have to hold shape, connect cleanly, seal where required and survive shipping without distorted flanges or bent access panels.
Flanges and Seams
Folded seams, rivets, welds, standing flanges and bolt patterns are controlled so sections connect without site modification.
Access and Service Features
Filter doors, inspection panels, damper frames, gasket lands and handles are planned for repeatable maintenance access.
Run-Level Packout
Similar duct sections can be packed by SKU, airflow module or job sequence so installers do not sort mixed cartons on site.
Our scope: fabricated duct and plenum hardware
We fabricate the cut, punched, formed, riveted, welded, finished and packed metal duct assemblies. Your HVAC or equipment team defines airflow performance, fan sizing, insulation package and system balancing.
02 / Duct & Plenum Types
Custom Airflow Hardware Built to Drawing
We manufacture the metal structures that move, split, filter and protect airflow in HVAC equipment, rooftop units, industrial ventilation and data center support systems.
Plenums HVAC Plenum Boxes
Supply, return and mixing plenums with flanged openings, access panels, filter slots and gasket lands for OEM HVAC systems.
- Materials Galvanized / stainless
- Features Doors, flanges, seams
- Use AHU, RTU and cabinet airflow
Transitions Transition Ducts
Rectangular-to-round, tapered and offset transition sections with repeatable flange fit and reinforced faces.
- Forms Tapered and offset
- Controls Twist and flange flatness
- Packout Run sequence labels
Equipment Equipment Ventilation Ducts
Internal and external duct housings for generators, electrical rooms, cabinets, enclosures and industrial machines.
- Features Brackets and covers
- Finish Powder coat or galvanized
- QC Fit and access checks
Filter Filter Housings & Damper Frames
Filter boxes, damper frames, service doors and air-control housings with gasket surfaces and hardware-ready access.
- Features Frames and doors
- Hardware Handles, hinges, PEMs
- Use HVAC and ventilation modules
03 / Technical Capabilities
Typical Duct and Plenum Fabrication Specification
| Materials | Galvanized steel, aluminized steel, stainless steel, aluminum and pre-coated steel |
|---|---|
| Processes | Laser cutting, CNC punching, forming, seam folding, riveting, spot welding, MIG/TIG welding and assembly |
| Common features | Standing flanges, access doors, filter slots, gasket lands, damper frames, brackets, handles and reinforcing ribs |
| Finishes | Galvanized finish, powder coating, stainless passivation, zinc plating for hardware and protective film |
| Quality controls | First article fit, flange flatness, diagonal checks, access door fit, seam inspection and run-sequence packout |
04 / Manufacturing Process
From Airflow Drawing to Fabricated Duct Run
01
DFM & Run Review
Confirm section sizes, flanges, service access, bend sequence, reinforcement and packout by airflow module.
02
Cutting & Punching
Cut blanks and punch bolt holes, access openings, slots and hardware points before forming.
03
Forming & Seaming
Form panels, return flanges and seams while controlling twist, diagonal dimensions and flange flatness.
04
Hardware & Assembly
Install hinges, handles, PEM hardware, brackets and access covers, then verify service fit.
05
Inspection
Check flange alignment, door operation, seam quality, coating condition and critical mounting patterns.
06
Run-Sequence Packout
Pack duct sections, plenums and accessories by SKU, installation run or equipment module.
05 / Why It Matters
What Makes a Duct Program Work
Airflow hardware can block an equipment launch when flanges drift, access panels bind or similar sections are packed without sequence control.
Flange Fit
Connecting faces need to stay flat and aligned after forming, welding, coating and shipment.
Service Access
Filter doors, dampers and inspection panels need clearance and repeatable hardware fit.
Shape Stability
Large panels, offsets and tapered sections need reinforcement to avoid racking and twist.
Installation Sequence
Labeled packout keeps similar duct sections from slowing installers or assembly teams.
Customer Project
Sheet Metal Ducts: Joint Sealing and Flow Resistance
Materials, fabrication decisions and results for an anonymous customer project.
Component reference image
The Customer Challenge
Leaking joints, high resistance and mismatched site interfaces increased energy use and installation work.
Project Measurements & Details
≤1%Air leakage
20%Flow resistance reduction
≤8 m/sAir speed
Results apply to the project configuration described on the linked page.
Read the Customer Project → 07 / Why Choose Us
Why OEMs Trust DRAmetal for Duct and Plenum Programs
01
Drawing-Based Project Review
Define the mating interfaces, critical dimensions, finish, inspection records and delivery requirements in the released drawing package.
02
Large-part forming control
Panel twist, diagonal drift and flange flatness are checked before parts reach the installation team.
03
Service hardware integration
Hinges, handles, PEMs, brackets and access covers are installed and checked as part of the build.
04
Run-level logistics
Duct sections ship by SKU, equipment module or job run so downstream assembly stays organized.
08 / Related
Related Fabricated Products
09 / FAQ
Custom Sheet Metal Duct and Plenum FAQ
Do you design the airflow performance?
We fabricate the metal duct and plenum hardware to your drawing. Your HVAC or thermal engineer defines airflow, pressure drop, insulation and balancing requirements.
Can you make galvanized duct sections?
Yes. Galvanized steel is common for duct and plenum work. We also support stainless steel, aluminum and powder-coated assemblies when the environment requires it.
Can duct sections be packed by installation run?
Yes. For repeated or project-based ductwork, we can pack by SKU, equipment module, airflow run or installation sequence to reduce site sorting.
Get Started
Need Ducts or Plenums
Need Ducts or Plenums
Built to Drawing?
Send your duct drawings, material, finish, flange details, access-panel notes and target quantity. Our engineering team will return DFM feedback and a production quote.