Stabilized valve

Patent metadata

Field	Value
Publication number	US-9422783-B2
Application number	US-201314015487-A
Country	US
Kind code	B2
Filing date	Aug 30, 2013
Priority date	Aug 30, 2012
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

An SPM valve for use in a subsea environment includes a spool selectively movable between first and second positions to thereby arrange the valve in respective armed and disarmed configurations. The particular arrangement of a supply port and discharge port with respect to the spool permits a pressurized working fluid supplied to the supply port to bias the spool to both the first and second positions once an external force is applied to the spool to initially set the spool in either the first or second position.

First claim

What is claimed is:

1. A valve for use as a sub plate mounted valve in a subsea environment, the valve comprising:
a valve body defining an upper end, a lower end and an interior cavity therein, the interior cavity defining a longitudinal axis;
a supply port extending laterally through the valve body and fluidly communicable with the interior cavity for supplying working fluid to the interior cavity;
an upper valve seat disposed within the interior cavity;
a lower valve seat disposed within the interior cavity;
a discharge port extending axially through the lower end of the valve body and the lower valve seat, the discharge port fluidly communicable with the interior cavity for discharging working fluid from the interior cavity;
a spool disposed within the interior cavity and selectively movable between an upper position wherein the spool is engaged with the upper valve seat to permit working fluid flow between the supply port and the discharge port and a lower position wherein the spool is engaged with the lower valve seat to prohibit working fluid flow between the supply port and the discharge port;
a valve stem housing extending axially from the valve body, the valve stem housing having a piston chamber;
a valve stem having a lower end that extends through a sealed opening into an interior of the spool, and a piston on an upper end of the valve stem and carried in the piston chamber;
a down stroke pilot port extending into the piston chamber above the piston for providing a pilot down stroke fluid pressure to move the piston downward and the spool to the lower position;
an upstroke pilot port extending into the piston chamber below the piston for providing a pilot up stroke fluid pressure to move the piston upward and the spool to the upper position; wherein
the stem is free of any spring biasing the stem either upward or downward;
the spool is configured to remain in the upper position in response to working fluid pressure in the interior of the spool once in the upper position in the absence of pilot up stroke fluid pressure;
the spool is configured to remain in the lower position in response to working fluid pressure on an exterior of the spool once in the lower position in the absence of pilot down stroke fluid pressure; wherein the valve further comprises:
a plurality of fins within the spool through which the stem extends; and
an upper counterbore in the interior of the spool that extends downward from the upper end of the spool and has a lower end no lower than upper ends of the fins, to assist in retaining the spool in the upper position once in the upper position.

2. The valve of claim 1 wherein the spool includes an upward facing shoulder on an external side thereof such that working fluid pressure in the interior cavity applied to the upward facing shoulder while the spool is in the lower position biases the spool to remain in the lower position.

3. The valve of claim 1 , further comprising a vent port extending laterally through the valve body, wherein the vent port is in fluid communication with the discharge port through the spool when the spool is in the lower position and wherein the vent port is fluidly isolated from the discharge port when the spool is in the upper position.

4. The valve of claim 3 , further comprising a spool seal disposed radially about the spool and axially between the supply port and the vent port, the spool seal operable to prevent fluid flow around an outer diameter surface of the spool between the vent port and the supply port.

5. The valve of claim 1 , wherein the discharge port is either fluidly coupled to a trigger valve that is operable to control working fluid pressure to a ram of a blowout preventer or directly coupled to the ram of a blowout preventer to control operation of the blowout preventer.

6. The valve of claim 1 , further comprising:
a lower counterbore within the spool that extends upward from the lower end of the spool, defining a downward facing shoulder that is in a plane perpendicular to an axis of the stem.

7. A method of controlling fluid flow in subsea environment, the method comprising the steps of:
providing a valve with an axis, a supply port, a discharge port, a spool axially movable between a closed position blocking flow of working fluid from the supply port to the discharge port and an open position allowing working fluid to flow from the supply port to the discharge port and into an interior of the spool, a piston chamber, a valve stem having one end connected to the spool and a piston on an opposite end that is carried in the piston chamber, the valve stem being free of any spring biasing the spool to the closed position;
applying opening pilot fluid pressure to the piston, causing the spool to move axially to the open position with a first end of the spool in engagement with a first seat;
while in the open position, biasing the spool in the open position with pressure of the working fluid within the interior of the spool, causing the spool to remain in the open position in the event the opening pilot fluid pressure to the piston ceases;
applying closing pilot fluid pressure to the piston, causing the spool to move axially from the open position to the closed position with a second end of the spool in engagement with a second seat;
while in the closed position, biasing the spool in the closed position with pressure of the working fluid on the exterior of the spool, causing the spool to remain in the closed position in the event the closing pilot fluid pressure ceases; and wherein providing the valve further comprises:
providing a plurality of fins within the spool through which the valve stem extends, each of the fins having a first end spaced from the first end of the spool and a second end spaced from the second end of the spool; and
a counterbore in the interior of the spool that extends into the spool from the first end of the spool a distance that is no greater than a distance from the first ends of the fins to the first end of the spool, to assist in retaining the spool in the open position once in the open position.

8. A valve for use in a subsea environment, the valve comprising:
a valve body and housing defining an interior cavity therein and a longitudinal axis;
a first valve seat disposed at a pilot end of the interior cavity;
a second valve seat disposed at a discharge end of the interior cavity opposite the pilot end of the interior cavity;
a supply port extending laterally through the valve body and fluidly communicable with the interior cavity for supplying working fluid to the interior cavity;
a discharge port extending axially through the second valve seat for discharging working fluid from the interior cavity;
a spool disposed within the interior cavity and selectively movable between:
an open position wherein a first end of the spool is in contact with the first valve seat such that a working fluid flow path is defined along an exterior of the spool between the supply port and the discharge port;
a closed position wherein a second end of the spool is in contact with the second valve seat, and wherein a sealing face of the spool circumscribes the discharge port such that the working fluid flow path is closed by the spool;
a valve stem that extends through a sealed opening into the spool and is secured to the spool with a plurality of fins in the interior cavity of the spool, the valve stem having a pilot piston within the pilot piston chamber;
a pilot fluid closing port leading to the pilot piston chamber to supply closing pilot fluid pressure to move the pilot piston, the stem, and the spool to the closed position;
a pilot fluid opening port leading to the pilot piston chamber to supply opening pilot fluid pressure to move the

Assignees

• Hydril Usa Distrib Llc

Inventors

• Gustafson Ryan
• Goode Matthew
• Bailey Parker

Classifications

• F16K3/246

  Combination of a sliding valve and a lift valve · CPC title

• E21B33/064 Primary

  specially adapted for underwater well heads · CPC title

• F16K31/122 Primary

  the fluid acting on a piston (F16K31/143, F16K31/163, F16K31/363, F16K31/383 take precedence) · CPC title

• F16K11/07

  with cylindrical slides · CPC title

• E21B33/0355

  Control systems, e.g. hydraulic, pneumatic, electric, acoustic, for submerged well heads · CPC title