This International Standard specifies functional dimensions for metal thermowell for thermo-meter sensors of nominal diameters ranging from 3 mm to 8 mm for use in process control.
BS IEC 61520:2001 history
2001BS IEC 61520:2001 Metal thermowells for thermometer sensors - Functional dimension
2001BS IEC 61520:2000 Metal thermowells for thermometer sensors. Functional dimension