WASTE-TO-ENERGY · FURNACE CHAMBER

Furnace chamber thermocouples built to survive the furnace, not just measure it.

High temperature, chlorine-bearing flue gas and high-speed fly-ash erosion attack at the same time. Here is how we stop it — five protection-tube designs, each matched to a specific failure mechanism, each with a service life we will quote up front.

WHAT KILLS THERMOCOUPLES IN THE CHAMBER

Three failure mechanisms, working together

A standard sheathed thermocouple is designed for a clean process. In a waste-to-energy furnace chamber it faces all three of these simultaneously — which is why life is measured in weeks, not years.

What a standard probe meets

  • Thermal: chamber temperatures swinging through 1000 °C+ with rapid cycling
  • Chemical: chlorine and alkali-rich flue gas attacking the protection tube from outside
  • Mechanical: fly ash and slag particles eroding the sheath at speed
  • Corroded or thinned sheath fails long before the element does
  • Alumina (corundum) tubes crack under thermal cycling, exposing the element
  • Replacement means access, permits and often an outage window

What we do instead

  • Tube first: the protection tube is selected from the failure mechanism, not from a catalogue default
  • Five variants: erosion, chlorine, peak temperature, combined erosion+corrosion, extreme temperature
  • Element second: imported sheathed insert, metal-clad against field interference
  • Life quoted: expected service life stated by tube diameter and installation position
  • Verified on site: designs tested in operating furnaces before being offered
  • All diameters, insertion lengths, threads and terminations made to order
THE FIVE DESIGNS

Pick by what is destroying your current probe

Every model below is a real production design with its own protection-tube technology. If you are unsure which fits your furnace, send us the furnace type, fuel and installation point — we will recommend, not guess.

WRNB-331HJ Wear-Resistant Alloy Thermocouple

For the common case: a probe that is being physically ground away by fly ash and slag.

PROTECTION TUBEModified wear-resistant alloy — high toughness, impact resistant, resistant to creep bending
ELEMENTImported sheathed Type K insert, metal-clad against electrical interference
RANGE0–1250 °C (Type K)
STRENGTHStable, high-accuracy signal in complex field conditions; extended service life
WRNB-332HJ Chlorine-Resistant Alloy Thermocouple HIGH-CHLORINE FUEL

For furnaces burning high-chlorine waste, where the tube is chemically eaten rather than worn.

PROTECTION TUBESpecial anti-corrosion alloy — more than 6× the corrosion resistance of ordinary alloys, especially against chlorine
ELEMENTImported sheathed Type K insert
RANGE0–1250 °C (Type K)
STRENGTHCorrosion resistance + wear resistance + high-temperature capability; resists bending
WRNB-333HJ High-Temperature Alloy Thermocouple UP TO 1400 °C

For the hottest measurement points — and a direct replacement for brittle ceramic tubes in Type S service.

PROTECTION TUBEHigh-temperature alloy reaching 1400 °C (ordinary alloys stop at 1250 °C)
ELEMENTImported sheathed insert; Type K (0–1250 °C) or Type S (0–1400 °C)
REPLACESAlumina / corundum tubes for Type S — which are brittle, crack easily and cannot take high-speed fly-ash erosion
STRENGTHHigh temperature + wear + corrosion resistance, without the fragility
WRNB-335HJ Overlay-Welded (Hardfaced) Thermocouple EROSION + CORROSION

For the worst combination — where the tube must resist chemical attack and physical abrasion at the same time.

PROTECTION TUBEBase wear-resistant alloy with high-speed automated overlay welding (hardfacing)
COATING QUALITYVery fine grain transition, uniform thickness — the reason it outperforms hand-welded repairs
RANGE0–1250 °C (Type K)
SOLVESCombined high-temperature corrosion and erosion/abrasion damage
WRNB-336HC Corrosion-Resistant Composite Ceramic Thermocouple UP TO 1600 °C

For extreme temperature zones and aggressive chemistry, including where ordinary ceramics would shatter.

PROTECTION TUBEComposite ceramic with special additives — acid and alkali resistant, thermally stable
TUBE QUALITYHigh bulk density, low porosity
MAX TEMPERATUREUp to 1600 °C; also usable as a Type S protection tube
THERMAL CYCLINGWill not burst under the repeated high/low cycling of furnace operation; available from Ø20 mm with composite ceramic liner
All five designs: insertion length, tube diameter, thread or flange, cable length and accuracy class are made to order. Send your installation drawing or a photo of the existing sensor and we will quote a matched design.
SELECTION GUIDE

Which one fits your furnace?

A starting point based on the failure mode you are seeing. Final selection is confirmed against your furnace type, fuel and installation point — at no cost.

What you observe Recommended model Why
Tube wall thinned or worn through; probe physically ground down WRNB-331HJ Wear-resistant alloy tube with impact and creep-bending resistance
Tube corroded, pitted or scaling; high-chlorine waste feed WRNB-332HJ Anti-chlorine alloy, 6× the corrosion resistance of ordinary alloys
Ceramic tube cracking or shattering; Type S measurement points WRNB-333HJ Ductile high-temperature alloy to 1400 °C replacing brittle alumina
Both corrosion and erosion present; previously tried wear alloys without success WRNB-335HJ Overlay-welded (hardfaced) surface — fine grain, uniform thickness
Extreme temperature zone; thermal cycling breaks conventional ceramics WRNB-336HC Composite ceramic to 1600 °C, dense and low-porosity, resists bursting
SERVICE LIFE & ECONOMICS

What a longer service life is actually worth

We quote expected life by tube diameter and installation position, so replacement intervals can be planned instead of discovered.

Series Typical service life Why it matters on site
Power plant / CFB boiler
WRNK-JYHD
6–24 months (by tube diameter) Reducing replacements from ten a year to two removes eight access and outage events — plus eight high-altitude or confined-space jobs.
Steel hot blast stove
WRNK-JYGT
3–12 months (by tube diameter) Vibration-resistant construction keeps the signal stable where mechanical shock is constant.
Cement kiln inlet/outlet
WRNK-JYSN
1 month and above Vacuum induction melting + remelting gives uniform hot strength in a highly abrasive, high-temperature zone.
Carbon baking furnace
WRNK-JYTS
≥ 3 months; 6–12 months when conditions are well controlled Accurate, uniform temperature is what decides anode quality — drift is a production problem, not just a maintenance one.
Why we do not publish prices: every sensor is built to the application — insertion length, sheath material, connection and termination are specified per site. Send your operating conditions and we will quote a matched design with a stated service-life expectation.
NAMED TECHNOLOGY

The materials behind these tubes

Each is a real, in-production protection-tube or sealing technology, tested on site until its service life was proven. We name them so you can specify them.

CrGuard™Austenitic high-temperature alloy with 40–65% chromium for hot strength, thermal-shock and wear resistance.
ClGuard™Anti-chlorine alloy for high-Cl flue gas — more than 6× the corrosion resistance of ordinary alloys.
HeatMax™High-temperature alloy reaching 1400 °C; the drop-in replacement for brittle alumina tubes in Type S service.
HardSurf™High-speed automated overlay welding with fine-grain transition — for combined corrosion and erosion duty.
CeramShield™Composite ceramic tube rated to 1600 °C, dense and low-porosity; will not burst under high/low cycling.
SealTight™Sealing process for metrology-grade RTDs — water and oil resistant, R0 drift under 0.15 °C after 672 h at temperature.
REQUEST A QUOTATION

Tell us what your furnace is doing to your thermocouples

The more you tell us about the installation, the more specific our answer. A drawing, photo or reference model number is welcome. We reply with a matched design and a stated service-life expectation.

We reply by email, normally within one business day. Your details are used only to prepare your quotation.