Self-contained depth compensated accumulator system

A self-contained expandable automatic pressure compensated accumulator system for storing and releasing hydraulic fluid energy for use by subsea equipment, the self-contained expandable automatic pressure compensated accumulator system comprising:

• a controller;
• a pressure source connected to the controller for supplying hydraulic fluid at a defined pressure as hydraulic fluid energy;
• a bidirectional valve connected:
• fluidly to the pressure source for transmitting the hydraulic fluid energy to subsea equipment;
• and
• electrically to the controller for controlling the hydraulic fluid energy to and from the subsea equipment based on commands from the controller;
• and
• an expandable multisided vessel fluidly connected to the bidirectional valve, the expandable multisided vessel comprising:
• a first bell endplate;
• a second bell endplate opposite the first bell end plate;
• a longitudinal axis between the first and second bell endplates;
• a plurality of axial folds formed contiguously between the first and second bell endplates creating a moveable flexible extruded metal dual thickness outer wall, the outer wall surrounding a pressure containing chamber configured to have a contracted pressurized volume and an expanded pressurized volume;
• and
• a bidirectional port formed in the first bell endplate or the second bell endplate connected to the pressure source and the bidirectional valve, wherein the bidirectional port is configured for both a flow of the hydraulic fluid energy to the bidirectional valve from the pressure containing chamber and a flow of the hydraulic fluid energy from the pressure source to the pressure containing chamber,
• wherein, as the expandable multisided vessel receives the hydraulic fluid energy from the pressure source:
• the plurality of axial folds, forming the moveable flexible extruded metal dual thickness outer wall, expand away from the longitudinal axis,
• the contracted volume, formed by the moveable flexible extruded metal dual thickness outer wall increases, increases the stored hydraulic fluid energy in the pressure containing chamber;
• and
• wherein as the expandable multisided vessel receives a demand for the hydraulic fluid energy from the subsea equipment:
• the plurality of axial folds contract towards the longitudinal axis,
• the expanded volume of the pressure containing chamber reduces via releasing stored hydraulic fluid energy, enabling the expandable multisided vessel to store retrievable subsea hydraulic fluid energy in close proximity to the subsea equipment under water, and
• wherein, as part of the releasing stored hydraulic fluid energy from under water on demand as changes in hydraulic fluid energy requirements for the subsea equipment changes, the expandable multisided vessel simultaneously counteracts hydrostatic seawater pressure applied directly on an exposed outer surface of the a moveable flexible extruded metal dual thickness outer wall with hydrostatic pressure of hydraulic fluid inside the pressure containing chamber.

A self-contained expandable automatic pressure compensated accumulator system for storing and releasing hydraulic fluid energy for use by subsea equipment, the self-contained expandable automatic pressure compensated accumulator system comprising:

• a controller;
• a pressure source connected to the controller for supplying hydraulic fluid at a defined pressure as hydraulic fluid energy;
• a bidirectional valve connected both fluidly to the pressure source for transmitting the hydraulic fluid energy to subsea equipment and electrically to the controller for controlling the hydraulic fluid energy to and from the subsea equipment based on commands from the controller;
• and
• an expandable multisided vessel fluidly connected to the bidirectional valve, the expandable multisided vessel comprising
• a first polygonal metal end plate;
• a second polygonal metal end plate opposite the first polygonal metal end plate;
• a longitudinal axis between the first and second polygonal metal end plates;
• a plurality of axial folds forming a moveable flexible outer wall contiguously between the first and second polygonal metal end plates, the moveable flexible outer wall surrounding a pressure containing chamber configured to have a contracted pressurized volume and an expanded pressurized volume;
• and
• a bidirectional port, formed in the first polygonal metal end plate or the second polygonal metal end plate, connected to the pressure source and the bidirectional valve, wherein the bidirectional port is configured for:
• a flow of the hydraulic fluid energy to the bidirectional valve from the pressure containing chamber;
• and
• a flow of the hydraulic fluid energy from the pressure source to the pressure containing chamber;
• and
• wherein, as the expandable multisided vessel receives the hydraulic fluid energy from the pressure source:
• the plurality of axial folds forming the moveable flexible outer wall expand away from the longitudinal axis,
• the contracted volume formed by the moveable flexible outer wall increases, increasing the stored hydraulic fluid energy in the pressure containing chamber;
• and
• wherein, as the expandable multisided vessel receives a demand for the hydraulic fluid energy from the subsea equipment:
• the plurality of axial folds contract towards the longitudinal axis,
• the expanded volume of the pressure containing chamber reduces releasing stored hydraulic fluid energy, enabling the expandable multisided vessel to store retrievable subsea hydraulic fluid energy in close proximity to the subsea equipment under water, and
• wherein, as part of the releasing stored hydraulic fluid energy, the expandable multisided vessel simultaneously counteracts hydrostatic seawater pressure outside of the moveable flexible outer wall with the hydrostatic pressure of hydraulic fluid inside the pressure containing chamber.