US 4,399,871 A · Chemical injection valve with openable bypass

Abstract

A combination well flow control device having a passage therethrough for conducting fluids from the exterior to the interior of the tubing, this device having pressure responsive valve means therein for controlling flow of fluids such as well treating chemicals through the flow passage at very low rates and also having a bypass passage which is initially closed by a sleeve valve but which is openable to permit high injection rates therethrough as for injecting water or the like fluid into the tubing at a very high rate as for killing the well. When the sleeve valve has been moved to bypass opening position, the valve flow passage is short-circuited through the bypass, and in one embodiment that portion upstream of the sleeve valve is shut off. After the sleeve valve has been moved to open position, it will remain at that position. The device also includes a check valve for preventing backflow therethrough regardless of whether the bypass is open or closed.

Claims27

Dependent claims

A device for controlling flow between the interior and the exterior of a well flow conductor, comprising:

a. a housing connectable to said flow conductor and having inlet means and outlet means and a main flow passage connecting said inlet means with said outlet means;
b. annular valve seat means in said housing providing a seat surface surrounding said main flow passage;
c. valve means including a valve tip engageable with said seat surface for controlling flow through said seat;
d. a bypass passage communicating the exterior of said housing with said main flow passage at a location between said oulet means and said annular valve seat;
e. means initially closing said bypass passage and being movable to open position when the pressure at said outlet means exceeds the pressure at said inlet means by a predetermined amount;
and
f. valve means operator means, including:
i. means for biasing said valve tip towards a position of engagement with said seat surface, and
ii. pressure responsive means for biasing said valve tip away from said seat surface when the pressure exterior of said housing reaches a predetermined value.

6 more elements

A device for controlling flow between the interior and the exterior of a well flow conductor, comprising:

a. housing means connectable to said flow conductor and having inlet means and outlet means and a main flow passage connecting said inlet means with said outlet means;
b. annular valve seat means in said housing means providing a seat surface surrounding said main flow passage;
c. valve means including a valve tip engageable with said seat surface for controlling flow therethrough;
d. a bypass passage communicating the exterior of said housing means with said main flow passage between said valve seat means and said outlet means;
e. means initially closing said bypass passage and being movable to a position opening said bypass passage when the pressure at said outlet means exceeds the pressure at said inlet means by a predetermined amount;
and
f. valve means operator means, including:
i. bellows means having a pressure responsive surface and connected between said housing means and said valve tip, and
ii. expansible means in said bellows applying a force to extend said bellows for moving said valve tip into engagement with said annular seat surface when said force of said expansible means exceeds the force of the pressure at said inlet means acting on said pressure responsive surface of said bellows, said bellows contracting to move said valve tip away from said seat means when the pressure acting on said pressure responsive surface of said bellows develops a force exceeding the force of said expansible means in said bellows.

6 more elements

Dependencies are inferred from the claim text.

Chemical injection valve with openable bypass

Life of this patent

Chemical injection valve with openable bypass

Life of this patent

Abstract

Claims27