Superior Performance Delivered in Challenging 17-1/2” Section – UK Central North Sea


Challenging long, deviated 17 ½” section

Tertiary into Palaeocene transitions

Balder Tuff, Sele and Lista formations


17-1/2” EVOS™ 816 PDC

VENOM™ Cutter Technology (ARTIMIS™)


UK Central Offshore

North Sea

Customer Challenge

The key objective was to drill the Tertiary and Palaeocene at sufficient ROP and trip in the Sele formation for a planned bit and BHA change. The Balder is known for harsh conditions, often causing significant PDC cutter damage.

The 17 ½” section in this application has always been drilled with multiple bit runs.

Varel Solution

VES proposed the EVOS 816 bit with a unique and engineered cutting structure designed for optimum performance in challenging applications. The cutting structure was designed through a joint collaborative effort by VES, Aberdeen University and Oil & Gas Innovation Center (OGIC) Scotland.

Customer Value


The bit drilled further than planned and tripped in the Sele formation due to a BHA unrelated issue with clear pathway to drill much further.

Run inclination was 24°. The bit drilled 2,394m of Hordaland, Balder, Lista and Sele formations at an average ROP of 23m/hr.

The run saved two days drilling (Approximately $550K).

The EVOS platform delivered superior performance compared with relevant offset runs setting a new field record of 885m drilled per day.

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