Finned Tubular Air Heater

散热片加热管

Tubular element with a spiral steel or stainless fin welded along the sheath, raising heat-transfer area so a duct carries more kilowatts at the same sheath temperature.

Max medium temperature: 572 °F(300 °C)
Power range: 0.5 – 6 kW
Voltage: 220 / 380 V, 50 Hz
Sheath material: 10# steel, 304 stainless
Medium: Air
Mounting: Bracket, Threaded boss, Bore insert
Tube diameter: 0.63 in
Watt density guidance: up to 3.5 W/cm² (23 W/in²) in forced convection

Lead time: 15–25 days
MOQ: 10 units
Pricing: On application

Design notes

Three times the surface area in the same duct width

A finned element solves the problem that limits every air heater: air will only take so much heat from a given area of tube. Winding a continuous fin onto the sheath and welding it down roughly triples the effective surface, so the same duct cross-section can carry substantially more kilowatts without raising the sheath temperature that decides element life.

Fin material follows the air. Carbon-steel fin is standard for clean, dry heating. Stainless fin is used where the air carries moisture, food residue or mildly corrosive vapor, and where wash-down is part of the cleaning routine.

The trade-off is that fins need moving air. In still air a fin can actually make matters worse — it blankets the tube and the heat has nowhere to go. Finned elements belong in ducts, unit heaters and forced-convection ovens where a fan sweeps them continuously, and should be interlocked with airflow proving so they cannot energize against a stopped fan.

Features

Spiral fin continuously welded to the sheath — no loose contact resistance
Roughly 3× the bare-tube heat-transfer area
Carbon-steel or stainless fin to suit air quality and wash-down
Also supplied as unheated finned tube for steam radiator duty
Formed to duct width, bend form and bracket layout on request

Typical applications

HVAC duct heating and reheat batteries
Unit heaters and air curtains
Forced-convection drying ovens
Grain and timber kiln air heating
Steam radiator replacement (unheated finned tube)

North American build options

Voltage: 120 / 208 / 240 / 277 / 480 / 600 V @ 60 Hz
Threads: NPT or BSP cut to order
Flanges: ANSI B16.5 150# / 300#
Drawings: Issued in inches on request

These are build options, not stock items — the catalog part numbers above are 50 Hz with metric fine threads. State what you need on the RFQ.

Part numbers & dimensions

8 catalog part numbers in the JGF series

Part number	Voltage	Power	Notes
JGF-220/1.0	220 V	1 kW	Single hairpin, steel fin
JGF-220/1.5	220 V	1.5 kW	Single hairpin, steel fin
JGF-220/2.0	220 V	2 kW	W-bend, steel fin
JGF-380/3.0	380 V	3 kW	W-bend, steel fin
JGF-380/4.0	380 V	4 kW	Serpentine, steel fin
JGF-380/6.0	380 V	6 kW	Serpentine, steel fin
JGF-S-220/2.0	220 V	2 kW	W-bend, stainless fin
JGF-S-380/4.0	380 V	4 kW	Serpentine, stainless fin

Finned elements are usually made to the duct dimension. Give us the free width and depth, the airflow in m³/h and the required temperature rise and we will size the battery rather than the element alone.

Minimum order quantity for this series is 10 units. Dimensions switch between millimetres and inches with the unit toggle in the header.

Full specification

Sheath material: 10# steel or 304 stainless
Fin material: Carbon steel or stainless
Tube diameter: Ø16 mm
Max. medium temperature: 300 °C
Effective area gain: ≈ 3× bare tube
Airflow requirement: Forced convection; interlock with airflow proving
Voltage: 220 V or 380 V, 50 Hz
Power range: 0.5 – 6 kW per element

Questions engineers ask

When should I choose a finned element over a plain tube?

When the kilowatts will not fit the duct at a safe watt density. A finned element gives roughly three times the surface area in the same width, so you can carry the load without raising sheath temperature. The prerequisite is moving air — in still air the fin blankets the tube and makes the situation worse, not better.

Do I need an airflow interlock?

Yes. A finned element energized against a stopped fan fails quickly, and in a duct with combustible dust or product residue it is a fire risk. Wire a differential pressure switch or a sail switch into the heater contactor coil so the heater physically cannot run without proven airflow.

What is the unheated finned tube for?

It is a steam radiator element. Steam or hot water is passed through the tube and the fins release the heat into the room, replacing a conventional hydronic radiator in workshops, greenhouses and drying rooms. It is the same finned tube without a resistance coil inside.

Watt-density figures and temperature limits on this page are design guidance, not warranties. The safe value for your installation depends on the medium, its flow and how the element is mounted — which is why we ask for the duty rather than only the part number.

Commonly specified with