may be used as the cooperating flange under certain conditions shown positioned between the opposed flanges 12 and 13 is the emergency release tool 20 release tool 20 is transported and positioned by means of a remotely operated vehicle rov 21 the remotely operated vehicle is connected to the surface by a suitable umbilical cord 22 that contains both the conductors for sending control signals to the rov as well as cables for supplying power to the rov in those cases where the rov is not self contained various offshore oilfield service companies offer rovs that are capable of lifting weights of 100 to 500 pounds and supplying hydraulic power to operate various wellhead equipment these vehicles are all provided with freedom of motion to accurately position themselves or the equipment on the wellhead referring now to fig3 and 4 there is shown the details of the emergency release tool 20 the tool consists of a c shaped frame member 30 that is provided with an opening having dimension a which is sufficient to encircle the members that are to be separated as explained above the member 30 is not a structural member and must have only sufficient rigidity for installation and to support the hydraulic jack means that are used for forcing the two members apart hydraulic jack means 31 are positioned on the frame member and located so.