HVAC Sheet Metal Parts, Casings & Air Handling Enclosures
Casing panels, fan and blower housings, damper frames, filter boxes and plenum sections for ventilation and air handling equipment — fabricated to your drawing with the panel stiffness, sealing detail and finish your specification calls for.
Sheet Metal That Has to Move Air, Not Just Hold It
An air handling casing is judged on how the air behaves, not on how the steel looks. A flat panel that is too thin will drum under pressure and radiate noise; a joint that is not sealed will leak at the corner; a frame that is not square will make the filter and coil sections fight each other on assembly. Those are the details that decide whether the unit passes its test.
We fabricate casing panels, frames, damper and fan housings, and plenum and filter boxes to your drawing, with the panel thickness, stiffening and sealing detail that your design specifies. We make the metal; the refrigeration circuit, the fan selection, the electrical package and the airflow or heat-load calculation stay with you, and we say so clearly on every quotation.
Closer Look at This Enclosure Type
Representative photographs of the construction, interfaces and installation context for this product family.
Specifications at a Glance
| Parameter | Typical Specification |
|---|---|
| Typical parts | AHU and fan coil casing panels, fan and blower housings, damper frames and blades, filter and plenum boxes, transition and duct fittings, equipment skids |
| Materials | Pre-galvanized SGCC, cold-rolled SPCC, stainless SUS304 and SUS316L for hygienic or corrosive duty, aluminium 5052 |
| Thickness range | Panels 0.5–2.0 mm typical; frames and housings 1.5–3.0 mm; bases and skids up to 8.0 mm |
| Cutting & forming | Fiber laser cutting up to 3000 × 1500 mm, press-brake forming, roll forming where the profile suits it |
| Panel stiffness | Return flanges, swages, formed ribs and folded edges added to control drumming and deflection |
| Welding | TIG, MIG and spot welding with jigs to hold the frame square and limit distortion |
| Sealing detail | Gasket and seal grooves formed where the drawing calls for them; closed-cell gaskets can be fitted |
| Insulation provision | Panel build-ups, spacers and fastening points prepared for the insulation your design uses |
| Finish | Powder coating in any RAL, or mill galvanized and stainless finishes left uncoated where appropriate |
| Inspection | Squareness, panel flatness and weld quality checked before coating; records kept per batch |
The parameters above are representative of typical projects in this category. Your drawing defines the final specification, and every quotation states the scope it covers.
Popular Configurations We Manufacture
Every size and option is customised to your drawing. Use a configuration below as a starting point for your enquiry.
AHU & Fan Coil Casings
Panels, frames and corner posts that form the casing of an air handling unit.
| Material | Galvanized, stainless or aluminium sheet |
| Build-up | Panel thickness and stiffening set by your design |
| Sealing | Gasket grooves and sealed corner detail as drawn |
Fan, Blower & Damper Housings
Fabricated housings and frames around the moving parts of a ventilation system.
| Material | Galvanized steel, stainless for humid duty |
| Welding | TIG and MIG with jigs for square frames |
| Interfaces | Damper and fan mounting holes produced to drawing |
Filter, Plenum & Transition Boxes
Boxes and fittings that guide air between sections or filter it.
| Material | Galvanized and stainless sheet |
| Forming | Folded edges and reinforcement to limit panel movement |
| Fit-up | Matching flange patterns between connected sections |
Materials, Finishes & Customisation
Material choice
| Pre-galvanized SGCC | 0.7–2.0 mm — the default for indoor casings and ductwork |
| Cold-rolled SPCC | 0.5–2.0 mm — where a painted finish over bare steel suits the duty |
| Stainless SUS304 / 316L | 0.8–2.0 mm — hygienic, washdown or corrosive atmospheres |
Stiffness & sealing
| Panel stiffening | Return flanges, swages and formed ribs added where panels could drum |
| Corner detail | Folded and welded corners plus gasket grooves as drawn |
| Seal interfaces | Gaskets formed or fitted at joints that must hold pressure |
Finishes & options
| Powder coating | Full RAL range over pre-treatment for visible casings |
| Uncoated galvanized | Left as-is where the surface is protected or out of sight |
| Insulation provision | Fastening points and spacers prepared for your insulation build-up |
How This Product Moves Through the Workshop
Casing, housing and box drawings are reviewed for panel thickness, stiffening and interface flanges before cutting, so fit-up between sections is confirmed first. Panels and frames are laser cut, formed and welded with jigs that hold square, then corners and gasket grooves are finished. Squareness and flatness are checked on the frame, the unit moves to coating if the drawing calls for it, and gaskets or insulation provisions are added before packing. Assemblies are trial-fitted where the order covers more than one section.
- Drawing review with DFM feedback before production release
- Fiber laser cutting of the complete flat pattern in one set-up
- CNC press-brake forming, welding and grinding
- Coating applied before gaskets, hardware and glass are fitted
- First-article and sample inspection recorded for each batch
Common Questions About This Product
No. We fabricate the casing, housing and box metal to your drawing. Airflow design, fan selection, coil sizing, the refrigeration circuit and the electrical package stay with you. We are glad to give DFM feedback on how the sheet metal will form, seal and assemble, and that scope boundary is stated on the quotation.
Yes — we fabricate SUS304 and SUS316L casings, boxes and frames with the welded and finished joints hygienic duty requires. Tell us the atmosphere and the finish standard on your drawing and we will make to that specification.
Panel movement is controlled in the design of the part: return flanges, swages, formed ribs, folded edges and the reinforcement points your drawing calls for. We form stiffening to drawing and can flag during DFM review where a panel span looks likely to need more support.
Typically 0.5–2.0 mm for panels and 1.5–3.0 mm for frames and housings, with bases and skids up to 8.0 mm. Cutting covers sheets up to 3000 × 1500 mm so long casing panels can be produced in one piece.
We inspect dimensional accuracy, squareness, weld quality and seal detail before dispatch, and can record what we check. Pressure or airtightness testing of the assembled unit is normally part of your build and test process; if you need a specific check performed and witnessed at our end, state it on the order and we will agree the method in advance.
Guides for This Application
How to Control Welding Distortion in Sheet Metal
Why sheet metal weldments distort, and practical controls: joint design, weld sequence, tacking, heat input, f
Read guide304 vs 316L Stainless Steel for Enclosures: Which to Specify
304 or 316L for your enclosure? Compare corrosion resistance, formability, welding behaviour, cost difference
Read guideHow to Choose Sheet Metal Thickness for Enclosures and Cabinets
How to choose sheet metal thickness by application: panel stiffness, gauge versus millimetre, weight and cost,
Read guideSend Us Your Drawing
Tell us the enclosure you need, the environment it works in and the quantity — we will return engineering feedback and a quotation, typically within 24 hours on working days.