Non-Invasive Pipe Clamp Sensor Temperature Calculation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Non-invasive process fluid temperature calculation systems are less accurate compared to traditional thermowells, which can be problematic in applications where direct measurement is not feasible, leading to potential process disruptions and inaccuracies in temperature monitoring and control.

Innovation Solution

A non-invasive process fluid temperature calculation system using a pipe clamp sensor with an additional temperature sensor inside a housing, coupled with thermal insulation and a microprocessor for heat flux calculations, dynamically adjusts thermal impedance to accurately estimate process fluid temperature by combining skin and terminal temperature measurements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a non-invasive pipe clamp sensor is used to measure temperature, then the system avoids process intrusion and thermowell damage, but the temperature measurement accuracy deteriorates

Engineering Contradiction:
Improvesystem reliabilityVSAvoidtemperature measurement accuracy
Core Design Contradiction:
ReliabilityVSMeasurement precision

Solution Approach 1:

The patent introduces thermal insulation material as an intermediary between the pipe clamp sensor and the ambient environment. This intermediary reduces unwanted heat transfer pathways, allowing the sensor to more accurately measure the pipe temperature which correlates to process fluid temperature, thereby improving measurement precision while maintaining the non-invasive approach

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the thermal parameters of the measurement system by adding thermal insulation, which modifies the heat transfer characteristics. This parameter change reduces thermal losses and improves the accuracy of temperature measurements without requiring process intrusion or thermowell installation

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If a thermowell is used for temperature measurement, then measurement accuracy is improved, but the system complexity and risk of structural failure increase

Engineering Contradiction:
Improvetemperature measurement accuracyVSAvoidinstallation complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts the temperature sensing function from the process fluid environment by using a non-invasive pipe clamp sensor that measures pipe temperature instead of directly measuring process fluid temperature. This eliminates the need for thermowell installation while providing sufficient measurement accuracy for process control applications

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of placing the temperature sensor directly in the process fluid (traditional approach), the patent inverts the approach by placing the sensor on the external surface of the pipe and using thermal correlation to determine process fluid temperature. This inversion eliminates process intrusion while achieving the measurement objective

Inventive Principle:
Principle #13The other way round (Inversion)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach provides more accurate temperature readings, reducing errors and improving process control by leveraging thermal impedance and heat flux calculations, thus overcoming the limitations of traditional non-invasive systems.

Implementation Method 1

the housing may be surrounded by thermal insulation to reduce heat loss from the housing

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Implementation Method 2

a first temperature sensor may be provided in the clamp assembly in thermal communication with an external surface of the process fluid conduit

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentEP3408632B1Non-intrusive process fluid temperature calculation system
Publication Date: 2023.05.24 ROSEMOUNT INC
  • EP3408632B1 patent drawingFigure 1
  • EP3408632B1 patent drawingFigure 2
  • EP3408632B1 patent drawingFigure 3

AI summary

A process fluid temperature calculation system includes a first temperature sensor disposed to measure an external temperature of a process fluid conduit. The process fluid temperature calculation system has a stem portion having a known thermal impedance. A second temperature sensor is spaced from the first temperature sensor by the stem portion. Measurement circuitry is coupled to the first and second temperature sensors. A microprocessor is coupled to the measurement circuitry to receive temperature information from the measurement circuitry and to provide an estimate of temperature of process fluid within the process fluid conduit using a heat flux calculation.