New Rigs Key To Russia's Upgrade аnd Drilling Plans

By Bojan Soc, March 12, 2014

when we executed a project which dealt with well difficulties at Samara region fields. The major challenge faced by Weatherford was deepening the wells with incompatible drilling conditions, particularly zones characterized by disastrous mud losses and water-bearing zones occurring in the same interval. We solved this problem by entering the zones of disastrous mud losses with the “floating liquid column” followed by the installation of a profile packer or cement bridges using the Brine Block® additive developed by Weatherford. Water zones were drilled using the bottomhole assembly with mudding bit subs. Currently, the possibility of using Weatherford Managed Pressure Drilling (MPD) technology is being discussed.

Horizontal Is Hip

Meanwhile, more sophisticated techniques enjoy growing demand and in 2013 horizontal drilling accounted for approximately 20 percent of total footage (Fig. 2). Rosneft led the way among operators (Fig. 3) and Eurasia Drilling Company (EDC) – among drilling contractors.

“Horizontal drilling is driven by the possibility to produce from a larger area, it provides wider reservoir contact via the same wellbore within the reservoir. Drilling a wellbore costs a lot of money. Until you reach a reservoir everything is investment and what you find in the reservoir provides your payback. Logically, you want to maximize payback and minimize upfront payments. So if you can use one wellbore with the same investment until you reach pay and if you can stay there, you can reduce the amount of wellbores to be drilled and reach a larger drainage area,” says OGE’s industry source.

“It’s a technological advantage, whereas 20 years ago it was ‘black magic’ and very difficult to control. Today, every company has the technology and the last step was the drilling rigs, which weren’t capable of drilling horizontal, directional wells with longer extensions. They had non-adjustable mud pumps, not enough hydraulic horse power and hookload capacity, so the new rigs addressed these issues. Now they have higher capacity, three mud pumps instead of two, better pump controls. In the past it was all mechanical drives, so it was on/off, while today with an AC drive you can adjust speed and pressure of the pumps, so with modern rigs you can perform longer horizontal extensions and achieve higher production rates.”