Glass Duplex Insulated K Type Thermocouple Wire With Heat-Resistant Inorganic Coating – Ninomiya K-Hh

Duplex-insulated thermocouple wires insulated and sheathed with glass fiber, and coated with heat-resistant inorganic coating to improve heat-resistance and insulation properties. Maximum operating temperature under normal condition is 350℃, and short-time maximum operating temperature under overheating condition is 400℃. K-Hh is improved version of K-H (glass coated thermocouple wire) with higher heat-resistance and insulation-resistance. Color of heat-resistant inorganic coating is natural-colored white. Identification is made by spiraled stripes on the surface appeared after yarning a colored thread, which is described in the Standards Table, together with braiding glass.

Heat-Resistivity Data of K-Hh

● Heat-resistance property of coating materials

Graph 1 shows heat-resistivity of our new coating materials measured by thermogravimetric analysis and compared with a conventional coating material. Pyrolysis begins at 500℃ for K-Hh and at 300℃ for K-H. The data proves that heat-resistivity of these materials are far more excellent than that of conventional one. Pyrolysis starting points were determined by tangent method using TGA chart.

Graph 1: Temperature-Weight Change Rate

● Heat-insulating property

Graph 2 shows changes in insulation resistance of our new coating materials under temperature changes compared with a conventional material. With the inorganic coating material, insulation resistance of K-Hh is high even under temperature at 400℃. This data is measured values for 450 mm. Source of the data is our in-house test result, but any value shown here is not guaranteed.

Graph 2: Temperature-Insulation Resistance