Thermal Conductivity Test System

(As per IS: 3346 – 1980, Hot Plate Method)

Thermal Conductivity Test System for Insulating Materials — As per IS 3346

The Thermal Conductivity Test System is designed for the determination of thermal conductivity of dry thermal insulation materials by the Two-Slab Guarded Hot Plate Method in accordance with IS 3346:1980. The method establishes a steady-state temperature gradient through the test specimens and determines thermal conductivity from the measured heat input, specimen thickness and temperature difference.

The system consists of a centrally located electrically heated guarded hot plate, surrounded by a guard heater to minimize lateral heat losses and promote substantially one-dimensional heat flow. Two identical test specimens are positioned on either side of the hot plate and are sandwiched between the hot surfaces and independently controlled cold plates. This two-specimen arrangement is a fundamental feature of the IS 3346 method.

The temperature of the hot and cold surfaces is accurately measured using suitable temperature sensors, while the electrical power supplied to the metered heating area is measured and controlled. The system is designed to achieve thermal equilibrium before the final readings are recorded. IS 3346 specifies that observations are continued at intervals of at least 30 minutes until successive calculated thermal-conductivity values meet the prescribed stability criterion

Salient Features

• Based on steady-state Two-Slab Guarded Hot Plate Method.
• Designed in accordance with IS 3346:1980.
• Suitable for testing thermal insulation and other suitable dry, homogeneous slab materials.
• Two identical specimens are tested simultaneously.
• Centrally located metered heater with surrounding guard heater.
• Independently controlled hot and cold surfaces.
• Accurate measurement and control of specimen temperature gradient.
• Measurement of heater power for thermal conductivity calculation.

Applications

The system is suitable for laboratory evaluation and quality-control testing of thermal insulation materials, insulating boards, slabs, sheets and other suitable homogeneous materials where thermal conductivity is required for material characterization, product development and quality assessment.

Applicable Standard: IS 3346:1980 — Method for the Determination of Thermal Conductivity of Thermal Insulation Materials (Two-Slab, Guarded Hot-Plate Method).