A pipe clamp including an annular clamp housing (12) having an opening (14) for inserting therein a pipe, opposing clamp members (16) located near ends of the annular clamp housing (12), one or more tightening elements (18) for fastening and tightening the clamp members (16) towards each other in a direction transverse to an axial length of the annular clamp housing (12), and an annular seal (20) placed in an inner perimeter of the annular clamp housing (12), characterised in that one portion of the annular seal (20) is attached to the annular clamp housing (12) with one or more mechanical fasteners (32) and another portion of the annular seal (20) is slidingly attached to the annular clamp housing (12) with one or more mechanical fasteners (34) so that the annular seal (20) is permitted to move and expand radially about as the pipe clamp (10) is tightened by one or more tightening elements (18).