Works: Plot No. 4,5 & 46C, Akshar Industrial Park, At Moraiya, Ahmedabad - 382213, Gujarat, India — +91 92279 94511
Fabrication Services — Heat Exchanger Fabrication

Steam Air Heaters

Modular, counterflow finned-tube coils that use steam to raise air temperature for combustion air preheating, dryer supply air, and process air heating — engineered up to 400°C and 60 bar steam duty.

Overview

An indirect steam-to-air heat exchanger, not a burner

A steam air heater is an indirect heat exchange device: steam flows inside finned tubes while air passes over the outside, with heat crossing the tube wall and fin surface without steam and air ever coming into direct contact. As steam gives up its latent heat, it condenses to water and drains away, while the air stream leaves the coil at a controlled, elevated temperature.

Large industrial units are built in a modular, counterflow arrangement — cold incoming air is first warmed by a condensate section, then brought to full temperature in the steam section — bolted together with interconnecting manifolds rather than housed in a single cassette, so any module can be removed, inspected, and replaced independently.

  • Individual elliptical, round finned, or smooth tube construction, or compact heat exchanger format
  • Carbon steel or stainless steel (304/316/321) tubes with aluminum or stainless steel fins
  • Air capacity up to 200,000 kg/h per unit; steam pressure up to 60 bar; rated to 400°C
  • Modular 2 or 3-section (steam / condensate / flash) counterflow design
Finned tube coil — steam air heater fabrication
How It Works

From steam duty to a modular, tested coil bank

Every steam air heater follows the same disciplined path through the shop.

1

Thermal & Section Design

Air volume, discharge temperature, and available steam pressure are rated to size the steam, condensate, and optional flash sections.

2

Finned Tube Fabrication

Elliptical, round, or smooth tubes are finned in aluminum or stainless steel to the required surface area.

3

Module & Header Assembly

Finned tube bundles are assembled into bolted modules with steam inlet and condensate outlet headers.

4

Casing & Manifold Integration

Modules are mounted in the duct casing and connected by interconnecting manifolds in counterflow arrangement.

5

Testing & Dispatch

Coils are pressure-tested, insulated as specified, and prepared for shipment.

Interactive Tool

Steam pressure → achievable discharge temperature

Drag the slider to see approximately what discharge air temperature a given steam pressure can deliver.

15 bar
Saturation Temperature
198°C
Achievable Discharge Air Temp
~178°C
Acid Dew Point Margin
Good
15 bar steam: saturates at roughly 198°C, giving an achievable discharge air temperature around 178°C after a typical approach temperature — comfortably above the ~120–150°C acid dew point range for sulfur-bearing fuel combustion air, protecting cold-end metal from corrosion.
Section Configuration

Two or three sections, always counterflow

Click a configuration to see how the counterflow arrangement is built.

2-Section: Steam + Condensate

Incoming cold air first passes over the condensate section, picking up residual heat from steam that has already given up most of its latent heat, then continues into the steam section for final heating to target temperature. This counterflow path improves overall steam economy versus a single-section design.

Suited to most industrial combustion air preheating and dryer air supply duties where a single steam pressure is available and flash steam recovery isn't required.

Standard industrial duty Improved steam economy Simpler manifold arrangement
STEAMCONDENSATEAir flows condensate → steam (counterflow)

3-Section: Steam + Condensate + Flash

A flash section recovers additional heat from flash steam generated when high-pressure condensate is let down to a lower pressure, further improving overall thermal efficiency. Air passes flash, then condensate, then steam sections in counterflow sequence before final discharge.

Specified where flash steam is otherwise vented to atmosphere or where maximum steam economy is a project priority — common on larger utility and process heater installations.

Maximum steam economy Flash steam recovery Large utility & process installations
STEAMCONDENSATEFLASHAir flows flash → condensate → steam
Tube & Fin Technology

Three tube geometries, matched to duty

01

Elliptical Finned Tube

Aerodynamic elliptical profile reduces air-side pressure drop and fouling compared to round tube, favored for high air-volume duty.

02

Round Finned Tube

Conventional round tube with aluminum or stainless steel fins — the standard, most widely specified construction.

03

Smooth Tube / Compact Design

Bare tube or compact heat exchanger format for lower-duty or fouling-prone air streams where fin cleaning access is limited.

Core Equipment

Shop capability behind every coil bank

Fin forming, module assembly, and testing equipment sized for steam air heater fabrication.

01

Finned Tube Forming Lines

Elliptical and round finned tube production in aluminum, stainless steel, and steel fin materials.

02

Module & Header Assembly

Bolted module fabrication with steam inlet and condensate outlet headers sized to the design.

03

Duct Casing Fabrication

Galvanized or stainless steel casing fabricated to the specified duct size and layout.

04

Manifold & Interconnection Piping

Interconnecting manifolds linking steam, condensate, and flash sections in counterflow arrangement.

05

U-Bend Tube Forming

U-bend tube fabrication that absorbs thermal stress without transmitting it to the tube-to-tubeplate joint.

06

Certified Welding Fleet

Code-qualified welders across carbon steel and stainless steel materials.

07

Hydrostatic Test Rigs

Pressure-test stations verifying steam-side integrity up to 60 bar design pressure.

08

Insulation & Lagging

Insulation and lagging applied to casings and headers per the thermal and safety specification.

09

Coating & Galvanizing

Hot-dip galvanizing or protective coating applied to frame and casing components before dispatch.

Design Specifications

Capability at a glance

Tube Construction
Elliptical, round finned, smooth tube, or compact heat exchanger
Tube Materials
Carbon steel; stainless steel 304, 316 & 321
Fin Materials
Aluminum or stainless steel
Frame & Casing
Galvanized steel or stainless steel (AISI 304/316) with insulation
Air Volume Capacity
Up to 200,000 kg/h per unit
Discharge Temperature
70°C to 210°C+, depending on steam pressure
Maximum Steam Pressure
Up to 60 bar
Maximum Operating Temperature
Up to 400°C (proprietary fin/tube designs)
Section Configuration
2-section (steam + condensate) or 3-section (+ flash)
Delivery Format
Modular, bolted sections ready for duct installation
Quality & Testing

Verified before it leaves the shop

PT

Pressure & Leak Testing

Steam-side hydrostatic testing verifies pressure-boundary integrity up to design steam pressure.

FI

Fin & Tube Inspection

Fin bond, tube layout, and surface finish inspected against the approved thermal design package.

MD

Modular Fit Verification

Bolted module and manifold interfaces dry-fit and verified before dispatch for straightforward site assembly.

Applications

Where our steam air heaters go to work

CA

Combustion Air Preheating

Raising cold combustion air above acid dew point for furnaces, fired heaters, incinerators, and steam reformers.

PM

Paper Machine Hood Air

Drying section air supply and moisture profile control using low-to-medium pressure steam.

DR

Industrial Dryers & Coating Lines

Process air heating for industrial dryers, coating lines, and drying tunnels.

OG

Oil, Gas & Petrochemical

Combustion air preheating for crude distillation units, fired heaters, and process furnaces.

FD

Food & Pharmaceutical

Rapid start-up, thermally stressed batch process heating for food, dairy, and pharmaceutical production.

CD

Corrosion-Prone Environments

Coated and stainless steel construction for highly corrosive industrial air streams.

Need a steam air heater engineered to your process duty?

Send us your air volume, target discharge temperature, and available steam pressure for a fabrication proposal.

Request a Proposal