The Subsea Test Tree is a valuable tool that can be used in various applications. There are some factors to consider when selecting a test tree. These factors include function, materials, construction, and operating costs. If these factors are not considered, severe consequences can result.
Function
The right subsea test tree selection depends on application-specific parameters, including water depth, sidetracking, and operational risk. In some applications, a horizontal tree will be more effective than a vertical tree, and vice versa. As a result, this question will continue to exercise in the minds of subsea engineers for some time.
A subsea test tree is a device that controls the flow of fluid from the well. It slows the flow and directs it through a series of valves to a flowline. It also provides access to various good intervention operations. Installation and operation of a subsea test tree require specialist equipment.
Materials
Subsea test trees can be used within a BOP stack. They allow for the sealing closure of multiple pipe rams, including shear rams. They can also be positioned between multiple shear rams.
Using common structural steels for the tree’s structural components is a good idea. These steels are flexible and conform to the design. As a result, it is important to consider their weldability when choosing the appropriate grade of structural materials. In addition, each weld connection is assigned an inspection grade based on the higher grade of the two joined components.
Construction
Standardization of Subsea Test Tree components can make the project run smoothly. These trees are designed and built specifically for the oil and gas industry and have been tested in a carbon capture environment.
Traditionally, subsea trees are bespoke, meaning there is no equivalent spare, leading to long downtimes. Operators must invest in spares for each application, which can be costly and time-consuming. Furthermore, changes to the design of the subsea tree can take time to accommodate once manufacturing has begun. This is why standardized subsea test trees are essential.
Operating Costs
A subsea test tree is a complex assembly of valves installed at the wellhead of an oil or gas well to control the flow of gas or fluids. It can be horizontal or vertical and is typically designed to meet a particular well’s unique physical and operating conditions.
The most cost-effective subsea production system depends on some factors, including the anticipated flow rates, reservoir study, and pressure. The specification requirements of a subsea test tree are dependent on these factors, as well as on the overall channeling of the resource.
The operating costs of operations like the PRT Offshore subsea completions can be significant. Operators are accustomed to bespoke trees, and there is a natural pushback against the notion of standardized units. However, a successful collaboration requires engineering and operating companies to move beyond these preconceived ideas.
Safety
A subsea test tree includes a ram lock assembly interconnected to a latch head assembly. This ram lock assembly provides a secure seal between multiple pipe or shear rams. The principles of the invention also provide methods for servicing subsea wells.
The subsea test tree includes a shut-in safety system, which controls subsea systems and equipment. This system addresses the desire for a minimal probability of failure on demand while minimizing electronics subsea. It also provides fail-safe electronic systems and diagnostic testing capabilities.
Subsea test trees can be designed to be used in deep water and can withstand the rig’s dynamic pressure. For example, a subsea test tree can be used to perform well testing and clean-up operations. A subsea test tree can be equipped with a safety shut-in system that allows it to close a well without human intervention.
