Rosemount™ X-well™ Technology

Non-intrusive measurement instruments obtain measurements of the conditions inside a process containment barrier (i.e. a pipe or vessel) without the need for process penetrations.

Non-intrusive process temperature measurements incorporate pipe surface and a secondary temperature to calculate internal process temperature via a thermal conductivity algorithm. This calculation takes into account the thermal conductive properties of the assembly and pipe for reliable and accurate process temperature measurements.

Non-intrusive process temperature measurement uses a secondary temperature measurement and pipe characteristics to compensate for heat loss to the environment.

A properly installed thermowell will provide the highest accuracy temperature measurement but require penetration into the process. Incorrect installation and installations on small line sizes will lead to stem conduction error and ultimately decrease the overall performance of the temperature measurement. A standard surface temperature measurement removes the need to insert a sensor into the process and reduces the impact of small line sizes on the accuracy of the installation. However, surface measurements do not provide an accurate or repeatable process temperature measurement. Rosemount X-well Technology provides an accurate and repeatable process temperature measurement on all line sizes, conductive pipe materials, and ambient conditions.

The primary factor that affects non-intrusive process temperature measurement is the difference between process and ambient temperature. The greater the difference, the greater the uncertainty will be.

Accuracy is dependent on the application. Non-intrusive temperature measurement can be considered for non-critical control applications.

Traditional thermowell installations will provide the best time response in most applications, with a T90 typically falling between 30 seconds and 3 minutes. T90 is the time to reach 90% of the final value. Rosemount X-well Technology’s system time response varies with different pipe characteristics and process and ambient temperature ranges. Rosemount X-well Technology is most responsive when:

• Pipe material is highly conductive (ex: carbon steel)
• Pipe walls are thin (smaller pipe diameters and lower pipe schedules)
• Process is liquid
• Flow is at a high velocity

Emerson’s Temperature Product Advisor includes application-specific estimates of Rosemount X-well time response based on your inputs.

Yes. Similar to traditional thermowells, liquid measurement will generally have faster response time than gases.

Yes. No cutting or welding of the pipe is required for installation, making installation during operation possible.

Yes. Best practice is to insulate the device for best performance.

Yes, general plant calibration procedures and standards should be followed. Rosemount X-well Technology calibration closely follows the steps of a standard temperature calibration. Rosemount X-well calibration procedure trims are based on the uncorrected surface measurement. This procedure does not calibrate or change Rosemount X-well’s algorithm or its coefficients. Please refer to the manual for the associated transmitter used with Rosemount X-well for specific instructions on calibration.

Risk of process contamination, leakage, and measurement failure are drastically reduced or completely eliminated when compared to thermowell measurements, improving overall safety.

Installation and maintenance costs are reduced by 70% when using non-intrusive process temperature measurement, as no process shutdown or pipe modifications are required.

Yes. Non-intrusive measurements have a much lower risk of failure, as they do not come into contact with the process fluid.