Description
A Flanged Thermowell is a protective enclosure designed to isolate temperature sensors such as RTDs, Pt100 sensors, and thermocouples from pressurized, corrosive, or high-temperature process media while allowing easy sensor replacement without interrupting plant operations. The flanged connection provides a secure, leak-resistant mechanical joint, making it one of the most widely used thermowell configurations in industrial process plants.
The Aavad Instrument Flanged Thermowell (Model TW-FL-100) is manufactured from SS316 stainless steel and features a 1.5-inch Raised Face (RF) flange with a 12 mm stem diameter and 100 mm U-length. The corrosion-resistant SS316 construction makes it suitable for a wide range of industrial fluids, while the bolted flange connection ensures dependable sealing and mechanical stability under demanding operating conditions.
Unlike threaded connections, a flanged thermowell distributes mechanical loads across the flange assembly, making it suitable for medium to high-pressure systems, larger pipelines, reactors, pressure vessels, and heat exchangers. The design also enables convenient removal of the sensing element for calibration or replacement without draining the process or cutting the pipeline.
This standard straight-stem configuration is well suited for applications with moderate flow velocity. For installations involving higher fluid velocities or significant vibration, a tapered thermowell may provide improved mechanical performance and should be evaluated using ASME PTC 19.3 TW-2016 where applicable.
Key Features
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Rugged SS316 Stainless Steel Construction Provides corrosion resistance across organic acids, industrial process water, and general hydrocarbon streams.
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1.5″ ANSI/ASME Raised Face (RF) Flange Standardized flanged process connection ensures a leak-tight, bolted seal for high-pressure piping manifolds and reactor nozzles.
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Straight-Walled Shank Design Economical baseline geometry optimized for moderate-velocity flow applications without incurring unnecessary machining overhead.
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100mm Standard Immersion Length ($U$-Length) Ensures accurate temperature sensing penetration into standard 2″, 3″, and 4″ process piping without causing flow restriction.
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Online Instrument Maintenance Enables safe removal, recalibration, or replacement of RTD and thermocouple elements while the system remains fully pressurized.
Applications
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Oil & Gas Refineries & Hydrocarbon Processing Moderate-velocity liquid hydrocarbon headers, storage tank temperature loops, and utility headers.
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Chemical & Petrochemical Processing Process lines carrying non-aggressive solvents, cooling water returns, and polymer feed lines.
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Thermal Power Plants & Boiler Utilities Low-pressure steam lines, boiler feed water headers, and condenser circulation loops.
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Water & Wastewater Treatment Sludge lines, chemical treatment mixing tanks, and municipal distribution piping.
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HVAC & Industrial Utility Piping Chilled water loops, hot water supply lines, and building automation plant manifolds.
Datasheet
FAQs
1. What is a Flanged Thermowell?
A Flanged Thermowell is a protective housing that is bolted to a pipeline, tank, or process vessel using a flange connection. It isolates RTDs, Pt100 sensors, thermocouples, and other industrial temperature sensors from direct contact with the process fluid, protecting them from pressure, corrosion, erosion, and high temperatures while allowing easy maintenance and replacement.
2. When should I use a Flanged Thermowell instead of a Threaded Thermowell?
Flanged Thermowells are generally recommended for medium to high-pressure systems, larger pipeline sizes, and applications requiring a strong bolted connection. They provide superior mechanical stability and are commonly used in power plants, petrochemical facilities, refineries, chemical processing plants, and other demanding industrial installations where threaded connections may not be suitable.
3. What is an RF Flange?
An RF (Raised Face) Flange features a raised sealing surface that improves gasket compression and provides a more reliable seal in pressure piping systems. Raised face flanges are widely used in industrial process applications because they offer excellent leak resistance and compatibility with various flange standards and gasket materials.
4. Which sensors can be installed?
A flanged thermowell is designed to accommodate a wide range of industrial temperature sensors, including RTDs, Pt100 sensors, Pt1000 sensors, thermocouples, and other compatible temperature sensing elements. The thermowell protects the sensing element while maintaining accurate temperature measurement.
5. Why is SS316 used?
SS316 stainless steel provides excellent resistance to corrosion, oxidation, and many industrial chemicals. Its superior performance in water treatment plants, chemical processing, food and beverage, pharmaceutical manufacturing, marine environments, and general process industries makes it one of the most commonly selected materials for thermowells.
6. Can I replace the sensor without shutting down the process?
Yes. Since the thermowell remains permanently installed in the process connection, the temperature sensor can usually be removed, inspected, calibrated, or replaced without exposing the process fluid or depressurizing the system. This minimizes downtime and simplifies routine maintenance.
7. Should I choose a Straight or Tapered Thermowell?
Straight thermowells are suitable for many standard industrial applications with moderate flow conditions. Tapered thermowells are typically preferred for higher flow velocities, elevated pressures, and vibration-sensitive installations because they reduce drag forces and improve resistance to flow-induced vibration. Selection should be based on process conditions and, where required, ASME PTC 19.3 TW-2016 wake frequency calculations.
8. Can the Flange be customized?
Yes. Flanged thermowells can be manufactured with customized ANSI, ASME, DIN, JIS, or BS flange standards, various pressure ratings, flange sizes, insertion lengths, bore diameters, tip designs, and special materials to meet specific process requirements.
9. What industries commonly use Flanged Thermowells?
Flanged thermowells are widely used in oil & gas, petrochemical, chemical processing, power generation, refineries, water and wastewater treatment, steel plants, fertilizer plants, pharmaceuticals, food processing, pulp & paper, and other heavy industrial applications where reliable temperature measurement and equipment protection are critical.
10. Why Choose Aavad Instrument Flanged Thermowells?
Aavad Instrument Pvt. Ltd. Flanged Thermowells are precision-engineered for demanding industrial applications requiring reliable temperature sensor protection. Manufactured from high-quality materials such as SS304, SS316, SS310, Inconel, Monel, and other special alloys, our thermowells offer excellent mechanical strength, corrosion resistance, and long service life. We provide customized flange standards, insertion lengths, bore sizes, tip configurations, and process connections to suit power plants, oil & gas, chemical, water treatment, and other critical process industries.
