Abstract: A work arm system for a submergible chamber wherein a plurality of work arms are rotatably mounted to the chamber and are retractably extensible, so as to provide a plurality of tools for work at a subsea station, such as an offshore well-head station. One arm is provided with tool mounts at opposite ends, both ends being retractably extensible so that each end may alternatively be disposed to the subsea station. The present work arm system permits several work functions to be performed without resufacing of the chamber.

Abstract: A manned or remotely controlled submergible chamber or tool carrier is provided with tool connection and disconnection to the work arm at an underwater location. A plurality of tools are mounted in a rack and each tool may be selectively connected and disconnected to a hydraulic drive means at the outward end of the retractably extensible portion of the work arm. All tool changing operations are remotely controlled from within the chamber or a remote station, as the operator views the tool changing operation. This tool system permits continuity of work arm operations without the need for the chamber to surface for tool changing. This tool changing system is particularly useful in performing work functions on underwater wellheads.

Abstract: A submergible chamber is provided with flanges at the outward ends of chamber guide arms, wherein each flange engages a stanchion. In one embodiment the flanges are selectively electromagnetic with the stanchions, and with sufficient force, the flanges are held to the stanchions thereby positioning the chamber at a specific depth. In another embodiment, the flange is adapted to pivotally grip the stanchion, and further each stanchion is provided with a vertical gear rack engaging the driven gear of each respective work arm so as to accurately position the chamber at a specific depth whereat the clamp holds the chamber at that depth.

Abstract: A clamp engages an object such as a pipe at an undersea location and the clamp is connected by a wire to a surface station. At the upper end of the clamp is a mechanism for operating the clamp and this mechanism is provided with a seat for receiving a clamp arm of a manned submergible chamber. The manned submergible chamber grips the clamp mechanism and working in conjunction with the surface station closes the clamp on the pipe, and then after disengaging the work arm, the clamped pipe is brought to the surface station. The mechanism of this invention is particularly suited to offshore drilling operations as well as salvage operations. In another embodiment a hook is guided by the work arm to an object such as a pad eye and the hook engages the pad eye by the movement of the work arm. Once the pad eye is hooked the wire takes the hooked object to the surface.

Abstract: A work arm system for a submergible chamber wherein a plurality of work arms are rotatably mounted to the chamber and are retractably extensible, so as to provide a plurality of tools for work at a subsea station, such as an offshore wellhead station. One arm is provided with tool mounts at opposite ends, both ends being retractably extensible so that each end may alternatively be disposed to the subsea station. The present work arm system permits several work functions to be performed without resurfacing of the chamber.

Abstract: An apparatus having a bouyancy control tank mounted in conjunction with a submergible chamber, and being provided with a source of gas under pressure to the tank and wherein several vertically disposed pipes are arranged and constructed within the tank so that each pipe may be selectively opened from within the manned chamber for fluid communication from the tank to the ambient water below the tank. Pressurized gas to the tank forces water therein through a selected open pipe to the ambient water, so that a gas-water interface in said tank is attained at about the top free end of the opened pipe. To discharge gas under pressure from the tank, valves are mounted on the tank and which may be actuated from within the manned chamber or remotely, and with the discharge of the gas, water from outside the tank passes through the selected open pipe into the tank. The chamber is designed to provide a life-supporting environment so that bouyancy control operations may be conducted from within the chamber.

Abstract: A device is attachable to an outwardly extensible, rotatable arm of a manned submergible chamber and is formed with a horizontally pivoted gate to engage and hold a cable upon rotation of the arm. The device is provided with a track-mounted blade to sever the cable; the blade being actuated from within the manned chamber. In another embodiment, the device is capable of gripping the cable before severing, severing the cable and then permitting the severed cable to be lifted to the surface while continuing to grip the cable. The device is particularly useful for removing entangled cables from an underwater work area, such as an offshore drilling station.