Fabrication Profile
Supply Plenum Box
Multi-port discharge configuration with reinforced flange connections for central air handling units.
OEM / ODM Production
Custom batch & high-volume contracts
ISO 9001:2015 Certified
Rigorous factory QA & CMM checks
Custom HVAC plenum boxes
Precision-manufactured plenum boxes built strictly to your engineering drawings for commercial ventilation, rooftop air handlers, and heavy industrial air distribution systems.
CNC laser cutting and precision forming
Tight tolerance manufacturing to +/- 0.5 mm directly from your CAD and BIM engineering models.
Galvanized, stainless, and aluminum construction
Heavy-duty 16 to 26-gauge sheet metal options with continuous welded or Pittsburgh lock seams.
Custom supply, return, and mixing configurations
Built-to-print dimensions with pre-punched mounting flanges, internal acoustic lining, and damper collars.
Custom sheet metal plenum boxes
We manufacture precision supply, return, mixing, and transition plenum boxes engineered to match your HVAC system geometry and airflow requirements. Every unit is built to order with exact collar placements, damper knockouts, and flanged connections for seamless jobsite installation.
Our production line integrates high-speed CNC fiber laser cutting, automated panel bending, and robotic seam welding to produce rigid, low-leakage enclosures in galvanized steel, stainless steel, and heavy-gauge aluminum.
Optional acoustic and thermal insulation linings—including elastomeric closed-cell foam and perforated metal inner baffles—can be pre-installed in-house to streamline mechanical contractors' assembly timelines.
Any size & configuration
Supply, return, mixing, and transition boxes built to exact ductwork dimensions.
Tight tolerances
CNC laser cut and robotically folded within ±0.5 mm for airtight duct joints.
Certified quality
100% inspected seams aligned with SMACNA pressure class requirements.
Galvanized steel, structural aluminum, and 2B/brushed stainless steel with custom collar collars and lined acoustic baffles.
Core plenum box types & features
Engineered plenum components precision-formed from galvanized steel, stainless steel, and aluminum. Built to maintain static pressure and clean distribution across heavy-duty commercial and industrial HVAC duct runs.
Supply Plenum
Distributes conditioned air directly from the air handling unit across multiple duct branches with minimal pressure drop.
Return Plenum
Collects return air from multiple ceiling zones and ducted intakes before routing back for filtration and recirculation.
Mixing & Blending Plenum
Blends outdoor fresh air streams and recirculated return air evenly to prevent thermal stratification before coil entry.
Distribution & Transition Box
Transitions duct cross-sections between rectangular and round profiles while preserving laminar flow and static pressure.
From engineering review to certified shipment
Every part follows a controlled 7-step sequence with in-line checks at every workstation to ensure repeatable tolerances and surface quality.
Drawing Review
DFM analysis & CAD audit
Design validation, tolerance verification, and material gauge optimization before machine setup.
Precision Cutting
Fiber laser & punch press
High-speed CNC fiber laser cutting up to 20kW and multi-station punching for intricate profiles.
Forming & Bending
Multi-axis CNC press brakes
Automated panel bending and multi-axis CNC bending for tight radius accuracy and repeatable angles.
Joining & Welding
TIG, MIG & robotic spot welding
Certified welding processes with seam grinding, stud welding, and structural weld integrity.
Related reading: sheet metal welding processes
Sealing & Finish
Coating & gasket integration
Automated powder coating, anodizing, plating, and polyurethane foam-in-place gasketing.
QC & CMM Inspection
Dimensional & surface audit
Coordinate measuring machine (CMM) reports, optical scanning, coating thickness, and IP testing.
Custom Logistics
Packaged & exported globally
Heavy-duty custom wooden crating, anti-corrosion barrier wrapping, and international freight tracking.
Need first-article inspection or custom test plans?
We provide CMM coordinate mapping, optical surface inspections, weld test reports, and custom packaging designs tailored to your exact QA standards.
Material and finishing options
Select the optimal alloy, gauge, and protective treatment engineered to meet the exact thermal, acoustic, and environmental demands of your plenum runs.
Standard hot-dipped zinc-coated sheet offering cost-effective structural integrity and moisture resistance for HVAC ducting and plenum boxes.
Related reading: galvanized vs galvannealed steel
G90 / Z275 Zinc Coating (275 g/m²)
Target Plenum Applications
- Insulated supply and return air plenum boxes
- Acoustic-lined mixing chambers and drop-out boxes
- Commercial mechanical room transitions and collars
High-grade austenitic stainless steel engineered for sanitary cleanrooms, harsh chemicals, and high-temperature kitchen exhaust systems.
Pitting Resistance Equivalent Number (PREN 23-25)
Target Plenum Applications
- Commercial kitchen exhaust hoods and grease plenums
- Pharmaceutical and semiconductor cleanroom plenums
- Corrosive chemical vapor and marine air handling
Lightweight, non-magnetic material with excellent formability and natural oxide resistance for rooftop and high-humidity environments.
65% weight reduction versus structural carbon steel
Target Plenum Applications
- Rooftop air handler plenum boxes and penthouse louvers
- Pool room and humid environment distribution housings
- Weight-critical aerospace and marine ventilation runs
Factory-applied architectural coatings over galvanized substrate, delivering custom aesthetic matching for exposed ceiling ductwork.
Salt spray resistance up to 1,000+ test hours
Target Plenum Applications
- Open-ceiling retail and office exposed plenum boxes
- Architectural color-matched diffuser boots and transitions
- UV-stabilized exterior ventilation and intake boxes
Custom gauge sizing, acoustic lining, and certified finishes
We fabricate plenum boxes from 26 to 10 gauge sheet metal with internal fiberglass or elastomeric acoustic insulation and certified powder coating.
Product advantages
Manufactured to exact production tolerances for reliable field assembly and long-term durability.
Automated laser cutting and precision panel bending ensure parts match your exact engineering drawings.
Continuous seam welding and tight flanging minimize airflow and fluid leakage across all ducting and enclosures.
Powder coating, passivation, and electro-galvanizing shield structural surfaces against moisture and chemicals.
Built-in thermal barriers and acoustic dampening liners manage operating temperatures and attenuate sound.
Pre-punched mounting points and standardized interlocking tabs allow fast, repeatable on-site assembly.
Every production run includes CMM coordinate checking, dimensional reporting, and full material batch tracking.
Verify your tolerances and production specs
Send your technical CAD drawings for rapid DFM evaluation and custom quote turnaround.
Application scenarios
Custom sheet metal ductwork and ventilation systems fabricated to exact engineering specifications for mission-critical facilities.
Frequently asked questions
Clear answers about tolerances, insulation standards, and production capacity for custom HVAC plenum fabrication.
Related reading: louver and airflow design and perforated panels for ventilation.
Have a custom technical inquiry?
Send your CAD/STEP drawings for rapid engineering review and DFM feedback.
Related services & products
Discover our high-precision fabrication capabilities, specialized ventilation ducting, and custom fittings manufactured to international standards.
Sheet metal fabrication
Laser cutting, CNC panel bending, robotic welding, and complete mechanical assemblies tailored to your technical drawings.
Related reading: sheet metal assemblies
HVAC duct systems
Rectangular and spiral metal ductwork engineered for reliable industrial, commercial, and cleanroom air handling setups.
Custom duct fittings
Precision elbows, transitions, reducers, and dampers built with exact tolerances for seamless ductline integration.
Request a custom fabrication quote
Upload your CAD models or 2D technical drawings for precise DFM feedback and fast production pricing.
Send drawings for custom plenum box quote
Specialized HVAC plenum boxes, sound attenuator casings, and custom distribution fittings fabricated to exact duct specifications.
24-Hour turnaround
Receive comprehensive pricing and initial DFM feedback within one business day.
Strict confidentiality
Your intellectual property is protected under comprehensive bilateral NDA agreements.
Any file format
We work seamlessly with STEP, IGES, DXF, DWG, SLDPRT, and dimensioned PDF drawings.