3 4 one to the other for a stronger fixing rings identical to rings 30 40 described above can be used in combination with said bushes assembly is then identical to that described above identical reference numbers to those described above are used to identify elements that are identical or analogous in the following description of a second embodiment of the invention made with reference to fig6 referring to fig6 the connection means of the second embodiment of the invention are intended to allow end to end coupling of a pipe 1 identical to that described above and a pipe 11 having a terminal portion 12 which is free of any type of shoulder and which has an end face 13 the connection means of the second embodiment comprise both sealing means and also means for fixing the pipes to each other the sealing means comprise a seal 60 which comprises an outer tubular section 61 to overlap the terminal portion 12 an adjacent annular section 62 which projects inwardly of the outer tubular section 61 to cover the end face 13 of the terminal portion 12 and an inner tubular section 63 extending from the annular section 62 facing and at a distance from the external tubular section 61 the seal 60 comprises a rigid l shaped reinforcing insert 64 extending within the annular section 62 and the inner tubular section 63 the seal 60 can also incorporate an electrically conductive element to ensure electrical conduction between the pipes 1 11 to prevent a buildup of electrostatic charges the fixing means comprise a ring with a threaded section generally designated 70 for.