Abstract: A swivel for heavy loads includes two mutually rotatable parts (1, 2) adapted to transfer tensile forces between them during simultaneous relative rotation. The first part (1) has a first sliding surface (11a) and the second part (2) has a second sliding surface (8a). The sliding surfaces are adapted to be able to bear and slide against one another. The first part includes a housing (3) including a cylinder (6) having the first sliding surface (Ha) and the second part includes a piston (8) having the second sliding surface (8a). A hydraulic fluid is introduced between the first and the second sliding surface to normally keep them apart in a non-sliding relationship.