A tool body and a turning tool for grooving operations having the tool body include a fitting member extending along a longitudinal first axis for fixing the tool body to a machine. The tool body's upper and lower clamping members each having respective inner seating surfaces facing one another and separated by an intermediate gap in which a cutting insert is insertable. A major part of the lower inner seating surface extends along a second axis perpendicular to the first axis. The clamping members are movable toward one another by a tightening device in order to secure the cutting insert in the intermediate gap. The tool body is integrally formed in a unitary piece. A hinge joint is formed between the clamping members, such that they are movable with respect to one another by turning around an axis of rotation of the hinge joint, extending perpendicularly to the second axis.