Sanjack Group designed and manufactured single-column and dual-well thermal recovery wellhead & x-mas tree for onshore thermal recovery.

The wellhead & x-mas tree is 3.6m in height and 7.8t in weight.

We assembled 2 sets of wellhead & x-mas trees in one well slot.

These 2 sets wellhead & x-mas tree can work independently, save platform space and improve platform oil recovery efficiency.

This type of wellhead & x-mas tree has been already gotten National Utility Model Patent.

The Oil Well Structure

Single-column and dual-well thermal recovery wellhead & x-mas tree structure

1) Design of Sector Flange

In order to meet the requirement of 444mm center distance, casing head, casing head inverted slips, tubing head and adapter are designed into sector flange structure.

2) Design of adjust flange design

An adjustment flange is designed on the side of the throttle valve on the wing of the tree to ensure that the flow stroke of oil does not change during hot and cold recovery.

The adjustment flange will be installed when steam is injected and removed during cold production, so that the crude oil flow will not change.

3) Design of large ring plate and compensate core

The large ring plate is installed on the 30″ riser pipe to ensure that the ring plate will not be deformed when two sets of 300m long 9 5/8″ casing pipes are hung.

When 2 sets of 9 5/8 “casing are suspended on the large ring plate through the compensate core.

The core cannot be deformed. The core also plays the role of positioning, ensuring the center distance of two sets of the casing is 444mm.

4) Design of wellhead & x-mas tree stability

We designed support bolts under the casing head adjustment plate to ensure wellhead & x-mas tree stability. A huff ring is designed on both casing heads to prevent tilt.

5) Design of casing head positioning pins

Four positioning pins are designed on the big ring plate, and matching guide holes are designed on the small ring plate.

When the casing head is installed, the guide holes of the small ring plate are matched with the positioning pins on the large ring plate to ensure the installation accuracy of oil wellhead manufacture christmas tree at the two wellheads.

6) Oilfield application

Sanjack’s single-column and dual-well thermal recovery wellhead & x-mas tree were approved by CNOOC’s auditors and installed on the offshore oil recovery platform in May 2012. At present, the effect is good.