offshore oil rig

While Northern Oilfield Services is based in Williston, ND, we serve most of the western United States, including Wyoming. We specialize in helping oil companies extract oil. We do this by renting and services oilfield equipment, including hydraulic fracking equipment and drilling rental equipment. We also repair and maintenance all of our equipment, taking one thing off your plate and helping to eliminate downtime when something breaks. We also offer wellhead equipment and maintenance services.

We’ve been taking a look at oil wells here on our blog. In this blog post, we’ll dive into the different types of offshore oil wells. Contact us today to get started!


Offshore oil wells are further divided into two types:

  1. Subsea wellheads
  2. Dry wellheads, or surface wellheads

Subsea wellheads have the top of the well under water, whereas dry wellheads have the top of the well above water on the platform.


Wellheads are extremely important amongst oilfield drilling equipment. They provide the suspension points and pressure seals for the casing strings. The casing strings, or oilfield pipes that are cemented into the wellbore, help stabilize the borehole, help prevent blowouts, or where fluids flow uncontrollably, and prevent fluids from leaking into the ground around them. Wellheads usually work in conjunction with Christmas trees to help control the flow of fluids in the production phase of the well.

Subsea wellheads work to contain pressure, as well as seal off casing that is used in the drilling process. Interestingly, the subsea wellhead system is on the ocean floor itself, making its installation a tricky process that is done remotely with cameras.


Drilling in water has been around since 1891 when submerged oil wells were first drilled in Ohio in lakes. In 1896, oil wells were drilled for the first time in salt water in California. As oil production began to ramp up offshore, the United States created the Exclusive Economic Zone (EEZ), which included 200 miles of the ocean around a country’s borders. This grants the United States and all countries exclusive rights to the ocean and all that lies in it.

Drilling offshore has its challenges. But with the need for oil ever-growing and the oceans having a vast territory, offshore drilling is here to stay. The offshore oil industry continues to innovate in order to help mitigate these challenges, such as having a lot of the production operations subsea, which allows oil companies to get more oil at deeper depths.

Offshore oil platforms are communities amongst themselves, having everything workers need in order to do their jobs and live. Helicopters transport workers back and forth, and most stay for two week shifts. Offshore oil workers tend to earn more merely for the hardships of the job. Ships delivery supplies and transport waste to and from the mainland. Offshore oil jobs can be great career opportunities for those willing to do the work.


When you want the best, you call the best. Northern Oilfield Services offers the best oilfield rental equipment for your needs throughout North Dakota and the western United States. We keep your equipment up to code with our regular maintenance services, as well as provide any necessary repairs either on location or at our shop. We also have a large supply of wellhead equipment for rent or for sale, from casing hangers to chokes and flow tees. From crane services to pressure testing and well maintenance, we help to ensure that your oilfield jobs run smoothly, efficiently, and keep running with little downtime. Call us today for all your drilling rental needs!