ASTM E1137/E1137M-08 (R2020) PDF Download

The specifications for metal-sheathed industrial platinum resistance thermometers (PRTs) that are appropriate for direct immersion temperature measurement are set out in the ASTM E1137/E1137M-08 (R2020) standard. The standard applies to PRTs with a nominal resistance of 100 O or another specified value at 0 °C and an average temperature coefficient of resistance between 0 and 100 °C of 0.385%/°C.

The standard details the tolerances, resistance-temperature relationship, and physical, performance, and testing criteria for PRTs. This covers the specifications for materials such as sheaths, sensor components, insulation, end closures for connecting wires, epoxy, and connecting wires.

The PRTs must pass qualification tests to show that they meet the requirements for qualities like insulation resistance, resistance to temperature, minimum immersion length, pressure, thermal response time, vibration, self-heating, stability, thermoelectric effect, mechanical shock, and dimensions.

Additionally, the standard specifies the vocabulary, accuracy levels, and inspection criteria for typical industrial platinum resistance thermometers. It can be incorporated into the paperwork to back up bargaining and conversations about the acquisition of such thermometers. The International Temperature Scale of 1990 (ITS-90) is the basis for the temperature values listed in the standard.