Protection-tube material is selected from the actual failure mechanism at your measurement point — furnace type, fuel, flue-gas chemistry and installation position — then tested until the service life is proven.
The hardest measurement point in the plant: high temperature, chlorine-bearing flue gas and high-speed fly-ash erosion acting together. Ordinary thermocouples fail in weeks.
Each series below was developed against the specific wear mechanism of that process — not adapted from a general-purpose product.
| Industry | Measurement point | Series | Temperature | Service life & key design feature |
|---|---|---|---|---|
| Coal-fired power | CFB boiler, furnace and cyclone areas | WRNK-JYHD | 0–1300 °C | 6–24 months by tube diameter. Austenitic alloy with 40–65% chromium for hot strength plus thermal-shock and wear resistance. |
| Steel mills | Hot blast stove | WRNK-JYGT | ≤ 1250 °C continuous | 3–12 months by tube diameter. Vibration-resistant construction; resistance to oxidation, sulphidation, abrasion, impact and thermal shock. |
| Cement | Kiln inlet / outlet | WRNK-JYSN | 0–1350 °C | 1 month and above. Vacuum induction melting + electroslag / vacuum arc remelting for uniform hot strength and hot-corrosion resistance. |
| Carbon / anode | Baking furnace | WRNK-JYTS | 0–1300 °C continuous 1350 °C peak |
≥ 3 months; 6–12 months under well-controlled conditions. Special high-temperature corrosion-resistant alloy, selected for temperature uniformity — which is what decides anode quality. |
Where accuracy and stability matter more than ruggedness: environmental test chambers, muffle furnaces and heat-treatment furnaces.
Class A / AA (AAA) thin-film elements in Ø4 mm stainless sheaths, sealed against water and oil. Stability: R0 change under 0.15 °C / 0.10 °C after 672 hours at temperature.
Ø1 mm and Ø3 mm sheaths that bend easily and respond fast, with flat-pin cold-junction plugs. Class I accuracy per JJF 1262-2010.
Measurement standards covering sheathed thermocouple calibration (300–1100 °C) and secondary-standard Pt resistance thermometers (−80 to +300 °C). Calibration certificates can be supplied with shipments.
Send the furnace type, fuel, flue-gas chemistry, installation position and what your current sensor is doing. We reply with a recommended design and a stated service-life expectation.