A representative thermowell is machined from drilled bar stock to ensure a proper sensor fit (ex: an 0.260-inch bore matching an 0.250-inch sensor). A thermowell is typically mounted into the process stream by way of a threaded, welded, sanitary cap, or flanged process connection. The temperature sensor such as a thermometer, thermocouple, or resistance temperature detector is inserted in the open end of the thermowell and typically spring-loaded to ensure that the outside tip of the temperature sensor is in metal to metal contact with the inside tip of the thermowell. The use of welded sections for long designs is discouraged due to corrosion and fatigue risks.