Flow Switch Leak Detection in Nuclear Power Plants
FCI’s FLT93 Flexswitch is claimed to be the process industry’s most advanced heavy-duty thermal dispersion technology flow and level switch. The solution proves ideal for reactor core coolant, level interface detection & temperature, pump protection, flood alarm, condensate pot level, and turbine water level.
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Nuclear power industry process and plant engineers who need various alarms and indicators for use in liquid, air, gas, or for interface service will find that the FLT93 Series Flexswitch from Fluid Components International (FCI) provides a highly reliable solution.
Ideal for use in a wide range of nuclear power plant flow, level and temperature measurement applications, the switch provides dependable critical equipment protection and plant integrity validation, states the company. Applications include: reactor core coolant, level interface detection and temperature, pump protection, flood alarm, condensate pot level and turbine water level. It is ideal in any application where the measurement of both flow and temperature or level and temperature are important.
The switch’s single sensor design provides dual measuring functions. It helps nuclear plant operations save weight, space and costs over two or more discrete sensors. Operators also realize reduced qualification installation costs and complexity, adds the firm.
The FLT93 Flexswitch has been tested to IEEE 323-1983 and IEEE 344-1987, making it fully qualified for Class 1E safety related nuclear power plant applications. FCI maintains a 10CFR50 Appendix B Quality Assurance Program and complies with 10CFR21 and ANSI-N45-2. Both the insertion and in-line sensor versions are qualified for a 40-year life at 150°F. The FLT93 sensor is qualified to radiation levels of 2x108 rads. The FLT93 electronics are qualified to 5x105 rads for applications requiring an integral unit (sensor and electronics).
A dual-function instrument, the switch can be configured for flow or level sensing, flow + temperature sensing or level + temperature sensing. A single FLT measures and monitors flow or level and temperature simultaneously with excellent accuracy and reliability. Dual trip points and 6A relay outputs are standard and are assignable to flow, level or temperature, mentions the company.
The company’s unique sensor technology when combined with its Flexswitch temperature compensation circuitry provides users with unparalleled performance capabilities: It operates at a low process temperature range of -40 to 250°F [-40 to 121°C], a high temperature range of -40 to 455°F [-40 to 235°C], a process pressure rating of 2000 psig, and accuracy of ±5 % of reading on flow, opines the firm.
In water, the sensing element set point range is up to 0.01 to 3.0 sfps [0.003 to 0.09 smps], 3.0 Watt heater power, depending on the specific model configuration. In hydrocarbon-based liquids, the sensing element set point range is up to 0.01 to 5.0 sfps [0.003 to 1.5 smps], 3.0 Watt heater power, depending on the specific model configuration. In gases, the sensing element set point range is 0.25 to 120 sfps [0.076 to 37 smps].
A wide selection of standard and custom process connections can be provided. The electronic control circuit can be integrally-mounted with the sensing element, or it can be located in a remote location. The standard enclosure is a coated aluminum alloy. It can be used in Atex locations and is rated for Nema Type 4X (IP66) environments.
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