Combined Drilling

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Combined Drilling


the combination or alternation at intervals of different methods and types of drilling (percussion and rotary drilling, coreless and core drilling, and so on) in sinking a borehole. The main advantage of combined drilling over any other drilling method is that it permits efficient use of several types of drilling, each of which is most favorable under certain drilling and geological conditions, during the sinking of a hole.

The combined method is often used for drilling shallow holes during geological engineering studies, surveying and prospecting work, and prospecting for nonmetallic building materials, because the rock and soils near the surface of the earth are particularly diverse in their physical and mechanical properties. Portable and self-propelled rigs that make possible the combination of several drilling methods are manufactured for sinking such holes (usually to depths of 40–50 m). For detailed deep-hole prospecting for many minerals, coreless drilling is often combined with core drilling. In this case thick rock series having no mineral content are drilled through at high speed by the coreless method, and the rock strata with mineral content are drilled through by the core method, with careful recovery of the core. The combined drilling method is used for deep gas and oil drilling: thick viscous-plastic rock strata are drilled by the rotary method, but hard rock is drilled by means of turbodrills and electrodrills.


Vozdvizhenskii, B. I., A. K. Sidorenko, and A. L. Skorniakov. Sovremennye sposoby bureniia skvazhin. Moscow, 1970.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
The combined drilling results highlight a consistent sequence of alteration zoning across the Project, specifically with a generally oxidized upper argillic cap zone, characterized by calcite veining, bleaching, decalcification, clay alteration, and dissolution brecciation that transitions to silicification with depth.
Both ConocoPhillips and Oil Search are optimistic about the potential of the Nanushuk Formation on the North Slope following the combined drilling of nine delineation wells over the winter in the Greater Willow and Pikka-Horseshoe units.
With more than 40 years combined drilling industry experience the White brothers have garnered drilling know-how that they, and their customers, consider to be second to none.
This combined drilling program is the largest undertaken by Padbury and is part of a focused strategy to build the Peak Hill Iron Project base.
Eldfisk B is a combined drilling, wellhead and process facility at the Eldfisk oil field, which is located south of the Ekofisk field on the Norwegian Continental Shelf (NCS).
We expect to move quickly to absorb operations and to accelerate our combined drilling program.
A 75-foot reach cantilever with a combined drilling load capacity of 2.6 million pounds, enables the rig to operate over a large drilling pattern.
The hull for the MPF unit, a combined drilling, production, storage and offloading vessel, will be delivered by Cosco Dalian Shipyard, while engineering, procurement and construction (EPC) will be carried out by Dragados Offshore SA.

Full browser ?