Guided wave radar level gauging with probe retaining element

A guided wave radar level gauge system for determining a filling level of a product contained in a tank, which level gauge system comprises:

• a tank having an inside wall, a roof, a bottom;
• a transceiver for transmitting electromagnetic transmission signals and receiving reflected electromagnetic signals reflected at a surface of said product;
• a surface waveguide comprising a single conductor transmission line probe, connected to said transceiver, arranged extending vertically into said tank and configured to guide said electromagnetic transmission signals towards said surface and to guide said reflected electromagnetic signals back to said transceiver;
• processing circuitry connected to said transceiver and configured to determine said filing level based on received reflected electromagnetic signals;
• a plurality of retaining elements arranged in fixed positions in relation to an inside of said tank and spaced apart along said probe,
• wherein each of said retaining elements circumscribes said probe, and is configured to allow movement of said probe in a vertical direction relative said retaining element, and to restrict movement of said probe in a horizontal direction relative said retaining element.