AMETEK Land CDB Non-Contact Boiler Gas Thermometer

AMETEK Land CDB non-contact gas thermometer for boilers and incinerators

The AMETEK Land CDB is a fixed, non-contact infrared thermometer designed to measure the true temperature of the hot gas inside a boiler or incinerator, rather than the temperature of walls or deposits. It does this by “seeing” through the cooler ambient atmosphere to the main combustion product, hot carbon dioxide, and applying spectral filtering to the CO₂ emission. The result is a gas temperature that is unaffected by other gases in the sight path.

The name is a model code from the AMETEK Land furnace gas temperature range. The thermometer was first designed for incineration of waste and biomass, but it also serves furnace exit gas temperature (FEGT) measurement in power generation and industrial boilers, as long as the path length through the hot gas is long enough. Seven Star LLC supplies the CDB in Oman and the GCC as an independent supplier in Muscat.

CDB technical specifications

How the CDB measures gas temperature

A normal pyrometer looks at a surface. A flame or hot gas is not a surface, so its emission is selective: hot CO₂ radiates strongly in a narrow infrared band. The CDB is tuned to that band. Because the cold CO₂ in the surrounding atmosphere absorbs less of that radiation than the hot gas emits, the instrument can view across the furnace and respond to the hot gas along its sight path.

It works without touching the process, around the clock, with its sight path extended above the furnace bed. Output is a standard 4–20 mA signal on a two-wire loop, so the same pair of wires carries power and signal, and the reading goes straight to a DCS or PLC analogue input.

Mounting the CDB and System 4 accessories

The CDB fits the AMETEK Land System 4 accessory range, including air- or water-cooled jackets and air-purged sighting tubes. In a furnace this matters: the sighting tube keeps the optics clear of ash and condensing deposits, and a cooled jacket allows installation in hot locations where the 5 to 50 °C ambient limit would otherwise be exceeded.

Because the instrument is fitted externally, there is no interaction with combustion and little to maintain. The parallel beam of under 20 mm diameter to 900 mm helps to keep the target defined and the measurement independent of distance.

Where the CDB fits in the boiler control system

Gas temperature in the furnace exit zone indicates how much heat has been absorbed by the radiant section. In an incinerator the same signal supports compliance with minimum combustion temperature, and in a boiler it supports FEGT-based performance and fouling checks. The signal is a standard loop signal, so it can be wired alongside thermocouple readings for comparison.

Other AMETEK Land thermometers in the range measure surfaces instead of gas; for a hazardous-area surface pyrometer, see the SPOT+ pyrometers and their EXSH1 housing. The CDB is for gas temperature only.

Selection and ordering checklist for the CDB

• Expected gas temperature: the range is 400 to 1800 °C.
• Path length: the hot gas path across the furnace must be long enough for a stable reading.
• Mounting position: above the bed in an incinerator, or at the furnace exit in a boiler.
• Accessories: air- or water-cooled jacket, or purged sighting tube, for the ambient and dust conditions.
• Power and signal: a 24 V DC loop supply within 11 to 45 V DC.
• Atmosphere: confirm whether the area is classified, since this brochure does not list hazardous-area certification for the CDB.

Installation, set-up and maintenance of the CDB

Align the instrument so the sight path crosses the hot gas without being blocked by a cold wall, and fit a purged sighting tube where the furnace gas carries ash. Set the response time between 1 and 10 seconds to suit the control loop: a short value follows rapid changes, while a longer value smooths a noisy signal. The emissivity setting is adjustable from 0.1 to 1.09, and the setting used at commissioning should be recorded with the loop sheet.

Maintenance is light. Inspect the window or sighting tube purge, keep the loop supply clean and compare the reading with a reference at planned shutdowns. The specified drift of less than 1 °C per year means recalibration intervals can be long.

Typical applications in Oman and the GCC

Typical sites are waste-to-energy and medical or industrial waste incinerators, biomass and utility boilers and fired heaters. In the Gulf, the high ambient temperature near boiler walls is an important design point, and cooled jackets help to keep the instrument inside its ambient limit.

Information to send with your CDB RFQ

• Type of furnace, boiler or incinerator and the fuel
• Expected gas temperature and the length of the hot gas path
• Ambient temperature at the mounting point and any dust or ash
• Accessories needed, such as jacket and sighting tube
• Receiving system and loop supply
• Quantity and delivery location

Documents and quotation

The AMETEK Land CDB brochure is attached on this page.

Send the CDB part number with your furnace data and we will confirm the configuration and quote. Seven Star LLC is an independent supplier in Muscat.