What is the difference between a wellhead and Christmas tree?

Many times, the words Christmas Tree and Wellhead are used interchangeably; however, a wellhead and Christmas tree are entirely separate pieces of equipment. A wellhead must be present in order to utilize a Christmas tree and is used without a Christmas tree during drilling operations.

What is wet tree?

Wet tree systems can be used in deeper water, reaching the industry’s current capability of subsea completion technology for operating in water depths up to 9600ft. MODUs and drillships are used for drilling and completion activities. Wells are tied back through a common production system to the floating facility.

What is a wet tree oil and gas?

For dry tree production, the wells are essentially extended to a surface platform where personnel have ready access to the production tree for operations, maintenance and inspections. For wet tree production, the production tree is located on the sea floor, thousands of feet under water.

What is the function of Christmas tree?

A Christmas tree is a piece of equipment that provides flow control on a oil or gas well. Christmas trees are a vertical assembly of valves with gauges and chokes that allow for adjustments in flow control as well as injections to stimulate production.

What is Christmas tree in wellhead?

In the oil & gas industry, a Christmas tree is a piece of heavy equipment that controls the flow produced by a well. It is a separate piece of hardware that connects to the wellhead after the drilling has ceased and the well begins pumping oil or gas.

How does a subsea Christmas tree work?

The functional requirements of a subsea tree are broadly similar to those of a land or platform tree: It is a vital component in the well integrity barrier envelope. It attaches to the wellhead and directs flow through a series of valves to the flowline. It is used to isolate flow from the well.

What is a wing valve?

A wing valve is a piece of flow-control equipment used in oil and gas operations. It is part of a Christmas tree and used to shut in flow from a producing well. Subsea and surface trees have a large variety of valve configurations, including combinations of manual and actuated (hydraulic or pneumatic) valves.

What is well intervention in oil and gas?

A well intervention, or well work, is any operation carried out on an oil or gas well during, or at the end of, its productive life that alters the state of the well or well geometry, provides well diagnostics, or manages the production of the well.

When to use a dry tree well system?

When considering dry tree systems, planners should be aware of several considerations. Dry tree systems are typically used in water depths ranging from 500ft to 5600ft (see Figure 1), and are suitable for all reservoir geometries where a single drilling location can reach all well locations.

How are dry trees used in the Gulf of Mexico?

In the deepwater Gulf of Mexico, operators most often select dry-tree production and drilling (PD) platforms – Spars and tension leg platforms (TLPs) – to develop reservoirs with sufficient reserves to justify a production hub and with direct access to the development wells.

What’s the difference between wet and dry trees?

The main reason for this difference is that there is one production riser per each dry tree well vs. two production risers for four (or more) wet tree wells. The wet weight of the dual barrier dry tree and size of air cans increases significantly with water depth and internal design pressure.

Where does the water from a dry well come from?

A dry well is a subsurface storage facility that receives and temporarily stores stormwater runoff from roofs of structures. Discharge of this stored runoff from a dry well occurs through infiltration into the surrounding soils. A dry well may be either a structural chamber and/or an excavated pit filled with aggregate.