Stove Dome Thermocouple with Double Ceramic Protection Tube Assembly

Special Thermocouples: An Overview

Special thermocouples are designed for demanding and highly specific industrial applications where standard configurations may not suffice. These sensors are engineered with enhanced protection, customized assemblies, and application-focused materials to ensure accuracy, reliability, and longevity under extreme conditions. Whether operating in molten metal environments, fluidized beds, or specialized furnaces, special thermocouples are built to meet the unique thermal, mechanical, and chemical challenges of the process.

Working Principle

Like standard thermocouples, special thermocouples operate based on the Seebeck effect. Two dissimilar metals form a thermoelectric circuit; when the two junctions are at different Temperatures, a voltage is generated that corresponds to the Temperature difference. This voltage can be measured and converted into Temperature using standard calibration data. What distinguishes special thermocouples is their robust construction, protective assemblies, and optimized materials suited to extreme industrial applications.

Type R thermocouples consist of a Platinum (Pt) and Platinum-13% Rhodium (Pt-Rh) combination. They are used extensively in high-Temperature environments (0°C to 1600°C) and offer exceptional accuracy (±0.25%) and stability. They are ideal for use in metallurgy, glass, and ceramic industries due to their resistance to oxidation and thermal shock.

Type B thermocouples are made of Platinum-30% Rhodium and Platinum-6% Rhodium. Designed for extremely high Temperatures (up to 1800°C), they are commonly used in high-Temperature furnaces and molten metal applications. They have excellent long-term stability and an accuracy of ±0.50%, making them suitable for continuous use in extreme environments.

Type S thermocouples are composed of Platinum and Platinum-10% Rhodium and offer similar performance to Type R. They operate accurately up to 1600°C and are commonly used in laboratories, metal processing, and pharmaceutical environments where high accuracy (±0.25%) is essential.

Model SP2 – Manufactured by Ajmer Thermotech Pvt. Ltd.

Ajmer Thermotech Pvt. Ltd., an ISO 9001:2015 and CE certified company, manufactures the Model SP2 special thermocouple designed specifically for stove dome applications. This model features a noble metal thermocouple element encased in a robust double ceramic protection tube assembly, engineered to withstand the intense thermal and chemical environment found in stove domes and high-Temperature combustion chambers.

The dual-layer ceramic design enhances thermal insulation and provides superior resistance to corrosion, abrasion, and thermal shock, ensuring reliable long-term performance. The Model SP2 is particularly suited for applications where consistent and accurate Temperature readings are essential for Temperature Control and energy efficiency.

Ajmer Thermotech offers full customization of the SP2 model based on customer specifications, including thermocouple type (typically Type R, S, or B for high-Temperature stability), protection tube length, junction configuration, and terminal connection style.

With a focus on rugged construction and measurement accuracy, the Model SP2 provides dependable Temperature sensing in one of the most demanding environments. It is a trusted choice across industries involved in heavy process heating, metallurgy, and industrial furnace operations.