HWU Rig, HWO Rig – Everything You Need to Know
HWU Rig, HWO Rig – Everything You Need to Know
When it comes to the oil and gas industry, the HWU rig (hydraulic workover) is one of the most efficient tools in a drilling process. The tool is even considered the most cost-efficient method that people choose to repair all types of wells. On top of that, it can be implemented both onshore and offshore. But, how does hydraulic workover work? Well, this page will dig deeper into everything you should know about the use of this HWU.
Hydraulic Workover – Overview
HWU rig, HWO rig is actually similar terms. They are also called snubbing sometimes. The term is used to refer to an intervention method of wells. This method has been around for many years. It is even considered the pioneer of a well intervention method in the US.
Hydraulic workover was widely popular in the North Sea, especially in the early 90s. Today, the popularity of this well intervention method is still high in the country. Not only that, but the method is also frequently used by the global community, especially for offshore purposes along with the advent of coiled tubing with a large diameter.
Why Hydraulic Workover?
Hydraulic workover is chosen in the oil and gas industry for some good reasons. The method is seen as a cost-efficient method when it comes to fixing all types of wells. Aside from the cost-efficient reason, it is also versatile.
A hydraulic workover unit is a safe tool that can perform sand cleanouts effectively. Not only that but the tool is also a perfect option to repair casing leaks. Furthermore, you can also use it to perform change-out completions effectively.
You need to know that an HWO unit doesn’t only serve as a workover rig. It also comes with benefits over traditional rigs. For instance, the HWO unit is not only a small but flexible footprint with almost zero environmental impact. The tool will also provide you with fast (de) mobilization. It also comes with a modular approach and perfect control.
What Can a Hydraulic Workover Unit Do?
As a versatile tool, the hydraulic workout unit can also perform other tasks. These include well deepening, sand screen installations, repair of down howl safety valves, and casing window milling. You can also use the tool for cementing, tailpipe installation, tubing conveyed perforating, as well as plug and abandonments.
How Does Hydraulic Workover Unit Work?
Generally speaking, HWU rig, HWO rig is a technique intervention for wells that can be utilized to remove or install pipes (tubular) in or out of dead wells – wells without surface pressure –. Instead, they come with heavy mud or fluid in the wellbore. Most of the time, dead whells can’t sustain natural flow either. Hydraulic cylinders are often used to pull pipes out of the wells.
Operation Principle of Hydraulic Workover Unit
The operation principle of HWO usually involves a hydraulic “jacking ram” or jointed pipe. The tool is used to “snub” or push the pipe in the well. So, it can help the well against the well pressure. Once the jointed pipe reaches the desired well depth, a wide range of operations can be conducted.
The most important thing about this intervention method is that you can rotate the pipe. Not only that you can also circulate a large volume of fluids through the pipe. That is the main reason why the hydraulic workover unit is considered the most ideal tool for drilling or milling. This also makes the tool a perfect option to help you perform large clean-out operations of scale, sand, as well as general fill.
Applications of Hydraulic Workover Unit
You need to know that HWO units come in various sizes. The smallest size of the unit is usually focused on the application of thru-tubing. Meanwhile, the large and medium sizes of the hydraulic workover units are usually applied to produce tubing. Sometimes, they are also used in a wide range of large work to improve efficiencies.
Hydraulic workout units are now often implemented for heavy-duty well operations. It is generally used on both dead and live wells. Most of the time, the applications of the tool include large volume cleanouts. These can be bailing and scale milling operations.
The applications of HWO units also include large perforating operations in which perf guns are used to exceed the wireline’s weight limit. A hydraulic workout unit is also applied to heavy-duty fishing operations. Here, the pulling weights as well as set-down forces and large pulling are forecast.
Equipment of Hydraulic Workover Unit
When it comes to storage, transportation, rig down, and rig up operations, the equipment used in the HWO unit is very mobile and unitized. For this reason, the tool is considered the perfect tool for servicing operations of wells offshore. The very-mobile equipment also makes the tool perfect to be used in remote locations. The equipment of the HWO unit usually consists of high-pressure riser assembly, fluid pumping system, mast unit, pipe handling, and BOPS.