ring 14 u2032 via its outer face 15 u2032 is received in the bore 9 u2032 of the nut 8 u2032 and has a cylindrical bore 16 u2032 a holding face 17 u2032 extends radially relative to the longitudinal axis 2 u2032 and extends radially relative to the longitudinal axis 2 u2032 and is supported against the end face 3 u2032 of the connecting member 1 u2032 at its end face facing away from the holding face 17 u2032 the supporting ring 14 u2032 has a conical stop face 19 u2032 the cone angle of the conical stop face 19 u2032 corresponds to that of the conical bore 13 u2032 the nut 8 u2032 rests against the face 19 u2032 when tightened relative to the conical bore 13 u2032 the supporting ring 14 u2032 also has a supporting face 18 u2032 in the form of a conical bore whose cone angle corresponds to that of the conical bore 13 u2032 of the nut 8 u2032 the pipe 20 u2032 passes through nut through bore 11 u2032 the pipe end face 21 u2032 projects as far as the end of the receiving bore 5 u2032 in which it is guided by means of its outer face 22 u2032 the pipe 20 u2032 is also provided with a bulge 23 u2032 the bulge 23 u2032 has a first contact face 25 u2032 and a second contact face 26 u2032 the contact surfaces extend at least partially conically in accordance with the conical bore 13 u2032 of the nut 8 u2032 and the supporting.