Oil Drill Rigs: What They Are and Where They're Used

An oil drill rig is the core piece of equipment used to drill boreholes into the earth's crust to extract crude oil and natural gas. These range from small truck-mounted units used for workover operations to massive land rigs that can drill 9,000 meters deep. Every oilfield, no matter how big or small, relies on some form of drilling rig to get the job done.

People often think oil drilling is just one type of work, but in reality, rigs are used across many different stages of a well's life cycle. Exploration drilling, development drilling, workover and completion, and plug and abandonment — each uses a different type of rig for a specific purpose.

Common Applications of Oil Drilling Rigs

Exploration Drilling. Oil companies drill wildcat wells in unexplored areas to find new reservoirs. These wells are often deep and in remote locations, so they need large, powerful rigs that can handle any formation. Exploration drilling is high-risk, high-reward — you might drill 10 dry holes before hitting a commercial well.

Development Drilling. Once a reservoir is proven, companies drill production wells to extract the oil. Development drilling is more routine: you know where the oil is, you know the depth, and you're drilling multiple wells in a field. This is where mobile truck rigs really shine — you can move from one well pad to the next quickly and drill dozens of wells in a season.

Workover and Completion. After a well starts producing, it needs maintenance. Workover rigs are used to pull the tubing, repair the pump, stimulate the reservoir, or plug and abandon the well. These are usually smaller truck-mounted rigs because they don't need the same capacity as a drilling rig.

FAQ

Q: How much does it cost to drill an oil well?
A: It depends on the depth and location. A shallow onshore well might cost $500,000, while a deep offshore well can run into the tens of millions. Onshore drilling in the US or Middle East is much cheaper than offshore or in remote arctic locations.

Q: What's the difference between a drilling rig and a workover rig?
A: Drilling rigs are built to make new holes, with higher horsepower and larger derricks. Workover rigs are lighter, designed to service existing wells. You can use a drilling rig for workover, but it's overkill and wastes money.