Christmas tree
OwnerStuart Browninventor
Life of this patent
Estimating the term…
Abstract
A Christmas tree and a method of completing a well in a standard wellhead. The tree is presented as separately deployable upper and lower portions with the master valves contained in the lower portion so that they are located below the wellhead housing to lower the height of the tree while increasing well safety and integrity. The upper master valve is bi-directionally sealing to allow for pressure testing, removing the requirement for tubing hanger plugs.
Claims19
A Christmas tree for location at a standard wellhead, the wellhead having a wellhead housing and a tubing hanger extending into a wellbore from the wellhead housing, the tree comprising:
- an upper tree portion, including a swab valve, a flow wing valve and, at a lower end, being configured for connection in the wellhead;
- a lower tree portion, including one or more master valves arranged in a tubing, and being configured for connection and locking to an inner surface of the wellbore above the tubing hanger, wherein:
- the upper tree portion and the lower tree portion are configured to be coupled together;
- and
- an uppermost master valve of the one or more master valves is a bi-directionally sealing valve and the uppermost master valve is located below the tubing hanger.
A method of completing a well comprising the steps:
- (a) providing a Christmas tree comprising:
- an upper tree portion, including a swab valve, a flow wing valve and, at a lower end, being configured for connection in a wellhead;
- a lower tree portion, including one or more master valves arranged in a tubing, and being configured for connection and locking to an inner surface of a wellbore, wherein an uppermost master valve of the one or more master valves is a bi-directionally sealing valve;
- (b) providing a workstring, the workstring including a running stab at a lower end thereof;
- (c) locating the running stab in the lower tree portion;
- (d) running the lower tree portion into the well through a blow-out preventer (BOP);
- (e) attaching the lower tree portion to the inner surface of the wellbore above a tubing hanger extending from the wellhead so that the uppermost master valve is located below the tubing;
- (f) pressure testing against the uppermost master valve in the lower tree portion to determine well safety;
- (g) pulling the workstring and the BOP;
- and
- (h) landing the upper tree portion on the wellhead and coupling the upper and lower tree portions together.
Dependencies are inferred from the claim text.