What is Infrared Heaters

What is Infrared Heating?

Infrared heating is a form of heat transfer by electromagnetic radiation in the infrared part of the spectrum, typically with wavelengths from about 0.7 μm to 1000 μm. When this radiation hits a surface (people, products, machinery, walls), the surface absorbs the energy and its temperature rises without needing direct contact or moving air

For industrial uses, infrared heating is popular because it delivers energy directly to parts and products, giving fast response, high power density, and controlled heating zones for processes like curing, drying, shrinking, and preheating.

There is no loss of energy through any medium heating i.e air ,water etc — making IR one of the most efficient industrial heating methods.

How Infrared Heaters Produce Heat

Infrared heaters work on a simple principle:

1. Electric current flows through a filament or heating element (Tungsten, Kanthal, Nickel-Chromium, or Ceramic body).
2. The element becomes hot.
3. Instead of heating air, it emits infrared radiation.
4. These IR waves travel in a straight line and directly heat the surface they touch.

This is similar to standing in sunlight — you feel warm even if the air is cold.

Radiation vs conduction vs convection

Heat can move three ways, and IR heaters mainly use radiation.

- Conduction: Heat moves through direct contact inside solids (e.g., hot metal plate touching a workpiece).

- Convection: Heat carried by moving fluids (air, gases, liquids), as in hot air blowers, ovens, or furnaces.

- Radiation: Heat transferred by electromagnetic waves (IR, visible, etc.), requiring no air or contact, like sunlight or an IR panel.

How Infrared Waves Radiate Heat

All hot objects emit electromagnetic waves. Infrared heaters are designed to emit waves in a specific wavelength range, depending on temperature:

• Shortwave IR → Short Time quick Response →High Temperature →Very high radiant output
• Medium wave IR → intermediately Time Response → Moderate temperature → Balanced radiant heating
• Longwave IR → Steady and Slow Time Response → Lower temperature → Uniform heating

Infrared waves transfer heat by radiation, not by conduction or convection.

Types of Infrared Heaters

Below is the simplest, clearest classification used in industries.

1. Shortwave Infrared Heating Lamps)

Wavelength: 0.78 – 1.4 µm

Element: Tungsten filament in a quartz tube, very bright, runs at ~2000–2600 °C.

Response time: < 1 second

Applications: PET bottle blowing, printing, paper coating, drying, laminations, Automobile

Key feature:

⚡ Extremely fast heating, highest power density.

Characteristics:

 - Very high power density and fast response (on/off in seconds).

 - Strong penetration into some materials, good for high‑speed industrial processes.

 - Visible red/yellow glow, can cause glare.

2. Medium Wave Infrared Heaters (Quartz Tube MWIR)

Wavelength: 2 – 4 µm

Element temperature: 600–1000°C

 Element: Quartz tube with NICR wire or Resistance wire lower element temperature than short‑wave.

Applications: Powder coating curing, paint drying,

 plastics heating, automotive, food processing.

Key feature:

🔥 Good penetration into materials like powder coatings and plastics.

Characteristics:

 - Softer glow, less visible light.

 - Better absorption for many plastics, paints, powder coatings, and water‑based products.

 - Good balance of depth penetration and surface heating.

3. Longwave / Far Infrared Heaters (Ceramic IR Heaters)

Wavelength: 3 – 10 µm

Element temperature: 300–750°C

Element: Electrical Ceramic with NICR wire lower

surface temperature.Applications: Thermoforming, drying, textiles, pharma, packaging, food warming.

Key feature:

🔥Gentle heating and deep penetration, steady and slow, uniform heating.

Characteristics:

 - Gentle, uniform surface heating, comfortable “radiant warmth” for people.

 - Often used for comfort heating in factories, warehouses, churches, and for low‑temperature drying.

 - No visible light, typically slower response