ASTM International

Standard Test Methods for Sheathed Thermocouples and Sheathed Thermocouple Cable
 N E839

Annotation

This document lists methods for testing Mineral- Insulated, Metal-Sheathed (MIMS) thermocouple assemblies and thermocouple cable, but does not require that any of these tests be performed nor does it state criteria for acceptance. The acceptance criteria are given in other ASTM standard specifications that impose this testing for those thermocouples and cable. Examples from ASTM thermocouple specifications for acceptance criteria are given for many of the tests. These tabulated values are not necessarily those that would be required to meet these tests, but are included as examples only.

These tests are intended to support quality control and to evaluate the suitability of sheathed thermocouple cable or assemblies for specific applications. Some alternative test methods to obtain the same information are given, since in a given situation, an alternative test method may be more practical. Service conditions are widely variable, so it is unlikely that all the tests described will be appropriate for a given thermocouple application. A brief statement is made following each test description to indicate when it might be used.

The tests described herein include test methods to measure the following properties of sheathed thermocouple material and assemblies.

Insulation Properties:

Compaction—direct method, absorption method, and tension method.

Thickness.

Resistance—at room temperature and at elevated temperature.

Sheath Properties:

Integrity—two water test methods and mass spectrometer.