provided through the member 40 to permit hydraulic fluid or 34 mud 34 introduced to the pipe during the cutting operation to escape readily from the pipe specific channels corresponding to the bores 45 are not necessary in the embodiment shown in fig1 and 2 since the hydraulic fluid or 34 mud 34 may flow up through the slots 27 between the clamping elements 28 without undue difficulty turning now to fig4 and 5 again only parts of the embodiment which differ from the embodiment shown in fig1 and 2 will be described similar parts being provided with identical reference numbers the mandrel 9 supports a sleeve like member 50 which is mounted on the mandrel by means of bushes 51 52 for axial and rotational movement relative to the mandrel 9 the sleeve like element 50 has a waist portion 53 of enlarged diameter which defines a horizontal upper surface 54 and a horizontal lower surface 55 an outer sleeve 56 is provided which is rotatably mounted on the sleeve 50 the sleeve 56 is provided with a radially inwardly directed flange 57 at the lower end thereof and a bearing 58 of appropriate size is located between the upper surface of the flange 57 and the horizontal lower surface 55 on the waist 53 of the tubular member 50 a ring 59 is located in a recess formed at the top of the member 56 part of the ring projecting to form an inwardly directed flange which serves to trap an appropriately designed bearing 60 between the undersurface of the ring 59 and the horizontal upper surface 54 provided at the top of the waist 53 of the tubular member 50 it will be noted that the outer member.