Subsea hydraulic pressure boosting and regulating system

A system comprising:

• at least one hydraulic intensifier circuit accepting a supply pressure and returning a boosted pressure that is higher than the supply pressure;
• and
• at least one regulator that accepts the boosted pressure and returns a regulated lower, regulated pressure that is lower than the boosted pressure;
• wherein the hydraulic intensifier circuit further comprises:
• a reciprocating piston having a first side and an opposed second side, each of the first and second side having with a larger low-pressure region and a smaller high pressure region;
• a first three-way control valve selecting for supply pressure or vent to the first side low pressure region of the reciprocating piston;
• and
• a second three-way control valve selecting for supply pressure or vent to the second side low pressure region of the reciprocating piston;
• wherein a low pressure applied to the first side low pressure region moves the piston to create a high pressure on the second side high pressure region;
• wherein the low pressure applied to the second side low pressure region moves the piston to create the high pressure on the first side high pressure region;
• wherein at least the first three-way control valve further comprises:
• a casing defining a pilot port, a first operating port, a second operating port, and a third operating port;
• a lower spool configured to displace against a first spring bias in response to pressure at the pilot port;
• an upper spool defining an upper spool port in fluid communication with the third operating port and a lower spool port in fluid communication with the second operating port, the upper spool slidingly receiving the lower spool and displacing against a second spring bias in response to pressure from the lower spool, and having a hollow interior allowing fluid communication between the upper spool port and lower spool port when not under pressure from the lower spool such that the third and second operating ports are in fluid communication;
• and
• a seat insert slidingly engaged with the lower spool on a lower region thereof, the lower region of the lower spool blocking fluid communication with the first operating port when seated against the seat insert;
• wherein the lower spool is configured to engage against the upper spool upon a first displacement of the lower spool blocking the lower port of the upper spool and thereby blocking fluid communication between the third and the second operating ports;
• and
• wherein a second further displacement of the lower spool moves an inletted portion of the lower region into the seat insert allowing fluid communication between the second and first operating ports.

A system comprising:

• at least one hydraulic intensifier circuit accepting a supply pressure and returning a boosted pressure that is higher than the supply pressure;
• and
• at least one regulator that accepts the boosted pressure and returns a regulated lower, regulated pressure that is lower than the boosted pressure
• wherein the regulator further comprises;
• a pilot stage comprising:
• a pilot housing;
• an upper member in the housing biased toward a middle member in the housing;
• the middle member seating against the upper member and providing main pilot port pressure against the upper member and further seating against the pilot housing to selectively block supply pressure from a lower member;
• the lower member fixed to the pilot housing and providing a spring biasing the middle member against the upper member;
• wherein the upper member displaces the middle member to allow pressure into the lower member and pilot port when the bias of the upper member exceeds the spring bias combined with a pressure in the main pilot port;
• wherein the middle member displaces the upper member to seat on the housing and stops supply pressure into the main pilot port when the spring bias and pressure in the main pilot port exceeds the bias of the upper member;
• and
• wherein pressure from the main pilot port can separate the upper member from middle member and allow fluid to flow through the lower member, middle member, and upper member to vent via a passage in the pilot housing.