In the fields of metallurgy, chemical engineering, power and other industries, high temperature, strong wear and tear, and easy leakage pose severe challenges to temperature measurement equipment. Wear resistant and leak resistant thermocouples rely on their“Wear resistant, leak proof, high safety”Its core advantages make it a temperature measuring tool for scenarios such as circulating fluidized bed boilers, cement kiln tails, and refineries. This article will analyze the operating points and industry value of this device from two aspects: usage methods and application scenarios.

1、 Accurate installation: ensuring temperature measurement accuracy and equipment lifespan

Selection of temperature measurement points
Installation should follow“Reverse flow insertion”Principle: Insert the thermocouple facing the flow direction of the medium, ensuring that the measuring end is at the centerline of the flow velocity. For example, in a circulating fluidized bed boiler, thermocouples need to be inserted vertically into the bed to avoid an increase in thermal resistance due to particle deposition. If measuring solid temperature (such as cement clinker), the wear-resistant head should be tightly pressed against the surface of the material to reduce contact thermal resistance. Actual measurement data from a cement plant shows that correct installation can reduce temperature measurement errors±5℃Reduce to±1.5℃.

Insert depth control
For pipeline fluid temperature measurement, the insertion depth should be equal to the diameter of the pipeline1/2(such as diameter)200mmPipeline insertion100mm）. In high temperature and high pressure scenarios (such as main steam pipelines), shallow insertion design can be adopted, with an insertion depth of not less than75mmWhen measuring the temperature of the flue, the diameter4mThe insertion of the flue1mJust enough. If the insertion depth exceeds1mIt needs to be installed vertically and equipped with a support frame to prevent the thermocouple from bending or breaking due to its own weight or vibration.

Sealing and Protection
The outlet holes of the junction box should be installed facing downwards to avoid water vapor deposition; The reference temperature should be stable at0-100℃Within the range, stay away from heat sources or air conditioning vents. A certain refinery once caused insulation aging of compensation wires due to high junction box temperature, resulting in signal fluctuations. After adjustment, the failure rate decreased90%.

2、 Scientific use: extending lifespan and ensuring safety

Compensation wire matching
Compensation wires that match the thermocouple scale must be used (such asKType configurationKType of wire), and the polarity cannot be reversed. A certain power plant mistakenly used ordinary wires instead of compensating wires, resulting in a temperature measurement deviation of12℃Causing equipment malfunction. After proper connection, the error can be controlled within±0.5%Within.

Regular maintenance and cleaning
Clean the surface attachments of the protective tube (such as coal ash and oil stains) every quarter to prevent an increase in thermal resistance from causing the indicated temperature to be too low. Simultaneously check the aging condition of the sealing ring, and replace it immediately if cracks or deformations are found. The maintenance records of a boiling furnace in a certain chemical plant indicate that regular cleaning can extend the service life of thermocouples40%.

Standard Operation for Explosion proof Scenarios
In the use of explosion-proof thermocouples, it is necessary to ensure the ambient temperature-20℃to40℃Relative humidity≤80%And it is not allowed to0Zone (continuous explosion hazard zone) for use. When operating, the power must be cut off before opening the junction box to avoid igniting flammable gases with electric sparks. A certain refinery once caused an electric arc to ignite oil and gas in the junction box due to illegal operations, resulting in equipment damage.

3、 Typical application: solving industry temperature measurement problems

circulating fluidized bed boiler
adoptK1320Heat resistant and wear-resistant alloy protective tube, with a hardness ofHRC62-65Can withstand long-term erosion from fly ash. A power plant's actual test shows that the service life of this type of thermocouple is equivalent to that of ordinary products3Doubling, reducing the number of annual shutdowns and replacements80%.

Cement kiln tail smoke chamber
pass“The card sleeve screw is stuck”Sealed structure, blocking the infiltration of dust containing gases along the gaps between the wires. After being applied in a certain cement plant, the oil leakage rate has increased from the industry average3%drop to0.1%The following significantly reduces safety hazards.

Refinery reaction unit
equipd‖CT5Explosion proof shell, capable of withstanding10MPaPressure, suitable for high temperature and high pressure working conditions. In a catalytic cracking unit of a certain refinery, the thermocouple operates continuously2Annual leak free, longer lifespan compared to traditional products5Twice.

Conclusion

The wear-resistant and leak resistant thermocouple has achieved material innovation and structural optimization“Wear resistant, leak proof, high safety”The three major breakthroughs. Scientific installation and standardized maintenance are the key to unleashing its performance potential. In the future, with the further application of surface modification technologies such as ion implantation of tungsten carbide, the wear resistance and service life of such thermocouples are expected to reach a new level, providing more reliable temperature data support for industrial intelligent transformation.