Type R, S, K Thermocouples with Ceramic Sheathing
At Furn-Tek, we supply Type R, S, and K thermocouples with high-purity ceramic protection tubes — purpose-built for the harshest thermal environments, including assay furnaces, smelters, and industrial kilns.
Product Specification
Sheath Material:
High-alumina ceramic (Al₂O₃ 99%) or mullite (60–70% Al₂O₃)
Operating Temperature:
- Type R / S: up to 1600 °C
- Type K: up to 1260 °C
Platinum-based (R/S):
Excellent accuracy, corrosion resistance in oxidizing environments
Nickel-based (K):
Cost-effective, widely used for high-temp industrial systems
Optional inner protection:
Dual-sheath designs with ceramic inner + outer sleeves for extended service life
Lengths:
Custom-cut from 300 mm to 1,200+ mm depending on furnace design
Mounting:
Available with ceramic flanges, stainless steel brackets, or adjustable compression fittings
Typical Applications:
- Gold and platinum assay furnaces
- Glass and ceramics processing
- Aluminium smelting holding pots
- Heat treatment lines
- Laboratory and calibration-grade furnace setups
Technical Benefits:
- Withstands thermal shock and chemical corrosion
- Provides stable, repeatable measurements in continuous duty
- No metal sheath contamination in sensitive atmospheres
- Compatible with most industrial controllers and transmitters (mV output)
Whether you're upgrading an existing furnace system or specifying new instrumentation for OEM builds, Furn-Tek delivers precision-built ceramic-sheathed thermocouples — fast, durable, and furnace-ready.