Near bit ejector unit 'NBEU' tool?

Esteemed members of SPREAD,

Please may I share with you a recently new at-bit drilling technology that I have been meaning to seek more wells applications and evidence on.

Essentially this tool i.e. the 'Near bit ejector unit' (is installed just above the bit) with wells data evidence to suggest it can essentially reduce chip.-hold down effect i.e., In high highly overbalanced drilling environments. 

  • It achieves this by  diverting flow to create a vortex pressure reduction (suction) effect at the bit and - consequently - positively affects on bottom hole drilling performance.

What I can surmise is that.

I.NBEU  is installed above a bit and run into the hole as a part of BHA. (it's a small tool the size of a bit sub)

II.The drilling mud is fed through the drillstring to the bit as per standard norms..

III.On passing through the NBEU, a portion of drilling standpipe pressure (and hence drilling mud) mud is diverted at the NBEU direction from  downward to upward.  (I'm presuming the one or two upward-directed exit nozzles can be sized to best suit.).

  • What results is an on-bottom reduced chip hold down-pressured zone.
  • Delivering a vortex pressure reduction i.e. suction effect (in the bit’s on bottom zone –  to reduce chip hold down).
  • This makes rock destruction and on bottom drilling more effective and efficient.
  • The  cuttings are milled and chipped easier from the rock.

IV.In addition, the cuttings  are  carried  out faster  from the bits zone. No re-milling of cuttings.  Bit is worn-out less and works longer. 

In principle, we could potentially further optimize bit-on-bottom  hydraulics to get more flow rate to drill and optimise further. 

 SPE  149113.  Was published Methods of drilling rate increase, near bit ejector application.

  • Who has used this tool?
  • Anyone wanting to share experiences? (Dave Taylor says: “Privately through Dave Taylor if necessary, but NOT preferred”)
  • Why are we not seeing more use of this incredibly simple piece of engineering and tool that has resulted by company that makes this.
  • With many wells to show wellbore drilling optimization benefits to quote.

 As a result of near bit ejector unit’s application while drilling, the following results were provided:

I.     Rate of penetration increased

II.     Bit’s cost/ft saving reduce.

III.     Drilling time is reduced.

IV.     Wellbore quality is improved.  i.e. No washouts apparent.

Finally I have attached a secure read only of the original presentation I sourced wrt to this tool.

Note: Providing company details removed as per SPREAD REQUEST.


Notes from moderator (Dave Taylor):

  • I'm so glad to see Peter promoting disruptive technologies (as he done with Neodrill's CAN-ductor and so much more).
  • What keeps me content to provide this free forum is the nice combination of the not-yet-accepting “we've always done it that way” individuals and people like Pete who say “what do we need to do to make the answer yes?”
    • Unsure? Contact me ( an we can discuss how to (re)ignite Passion for Performance


Documents uploaded by user:

NBEU presentation rev 1 .pdf

5 Answer(s)

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Posted by

Peter Aird

Peter Aird

Drilling Specialist/Well Engineer/Training Consultant

Kingdom Drilling

Discussions: 113

Replies: 441

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