Custom Industrial Duct Fabrication

Malco fabricates custom duct systems for industrial process applications where off-the-shelf solutions don’t exist and lead time matters. From simple carbon steel flue gas ductwork to fully refractory-lined duct assemblies with integrated anchoring systems, we deliver finished, field-ready sections built to your engineering drawings and material specifications.

Our fabrication shop rolls plate in-house, producing cylindrical and conical duct sections up to 13 feet in outside diameter. We work in carbon steel, 304 and 310 stainless steel, and specialty alloys for high-temperature and corrosive environments. Every weld is performed under qualified procedures, and our ASME U, R, and S certifications mean we can fabricate to code when your application requires it.

We don’t operate like a typical job shop. Our roots are in refractory anchoring systems — the fasteners welded inside ductwork to hold refractory linings in place. That means we understand what happens to ductwork after it leaves our shop: how it gets lined, how it performs at temperature, and what fails when fabrication tolerances aren’t held. That knowledge is built into every duct section we produce.

Refractory-Lined Duct Fabrication

Most industrial duct fabrication shops build a shell and ship it. The customer then coordinates separately with a refractory contractor to install anchors and apply the lining. That approach adds lead time, coordination cost, and risk — because the anchor supplier, the fabricator, and the refractory installer are all working from different schedules and different quality systems.

Malco eliminates that complexity. As a manufacturer of refractory anchoring systems and a certified steel fabricator, we deliver duct sections with anchors already installed in the correct pattern, spacing, and orientation for your specified refractory lining. One purchase order. One quality system. One lead time.

This matters most in turnaround and shutdown work, where every day of downtime has a direct cost. When you need a refractory-lined replacement duct section and you need it fast, coordinating three vendors is a liability. A single source that understands both the steel and the refractory system is an advantage.

What We Deliver

• Bare duct shells and sections — rolled, welded, and dimensionally verified to your drawings, ready for field lining by your refractory contractor
• Anchor-ready duct assemblies — shells fabricated with refractory anchors stud-welded in place per your specified pattern, ready to receive castable, brick, or ceramic fiber lining
• Replacement duct sections — dimensionally matched to existing equipment for planned turnarounds or emergency repairs, with expedited lead times available
• Transition pieces and reducers — conical and eccentric transitions connecting ducts, stacks, and equipment of different diameters or cross-sections
• Casings and enclosures — penthouses, plenums, and exhaust enclosures fabricated in carbon or stainless steel for kiln, boiler, and process equipment applications

Applications & Industries

Our duct fabrication capabilities serve engineers, EPCs, OEMs, and maintenance teams across industries where high-temperature gas handling is a core operational requirement:

• Cement & Lime — kiln exhaust ductwork, preheater risers, cooler vent ducts, and calciner connections
• Power Generation — flue gas ductwork, economizer connections, SCR inlet and outlet transitions, and stack liner sections
• Petrochemical & Refining — process heater exhaust systems, flare header ductwork, and thermal oxidizer connections
• Pulp & Paper — recovery boiler ductwork, lime kiln exhaust systems, and precipitator inlet sections
• Steel & Metals — EAF exhaust ductwork, ladle preheater connections, and off-gas handling systems
• Pollution Control — ductwork connecting scrubbers, baghouses, oxidizers, and emission control equipment to process sources
• Renewable Energy & Waste-to-Energy — biomass boiler exhaust systems and gasifier duct connections

Why Malco

Refractory Expertise Built Into Every Duct

We’re not learning about refractory systems on your project. We’ve been manufacturing anchoring systems for over 40 years. When we fabricate a duct section, we understand anchor pull-out strength, thermal cycling effects on stud welds, and how lining thickness and anchor pattern interact. That knowledge prevents costly field rework and premature lining failures.

Single-Source Accountability

When you buy a duct section with anchors pre-installed from Malco, there is one company responsible for dimensional accuracy, weld quality, anchor placement, and delivery. No finger-pointing between a fabricator, an anchor supplier, and an installer. One call, one contact, one schedule.

Responsive Lead Times

Our shop is built for agility, not mass production. We carry standard plate inventory, maintain rolling and welding capacity for quick-turn work, and prioritize turnaround and emergency orders. When your project timeline compresses, we compress with it.

ASME Code Capability

Not every duct application requires code fabrication — but when it does, our U, R, and S stamps mean we can build to ASME standards without subcontracting. This eliminates delays and quality handoff risks on code-driven work.