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Performance loss and waste metrics
25 January 2006
At the recent Best Practices Forum on Tuesday 17th January on "Flat
Spot Reduction" it was discussed how to identify the opportunities
early enough to take advantage of them. For example how to identify,
measure and evaluate a well performance effectively?

The following information was provided by Peter Aird from Maersk Oil
on the day:

File one illustrates summarising a well from the daily reporting
system's by sub dividing the well into designated phases that have a
clearly defined start and end time applied. File two illustrates the
simple process applied in order to identify, measure and evaluate
phase performance/loss/waste aspects and applying three simple
formulae to derive the ultimate efficiency/ effectiveness of the
well results as drilled.

1. Total well time = Productive time + Significant loss
2. Productive time = Operational loss + Operational waste +
Technical limit.
3. Well efficiency can be evaluated = Technical limit / Total well
or TL =
TWT - SL + OL + OW

From the example files provided it can be viewed that this well
example (i.e. A 2005 'North Sea 'dry hole Exploration well', i.e.
one with low reportable loss indeed (e.g. 6.5hrs eqpt, and 22hrs
waiting on weather). Was in fact evaluated when based on truly
representative data with a Well efficiency of only = 53% (Or where
47% of the time taken was in fact identified as lost/wasted.)

A typical well can be reviewed in 3-4hrs using this process. The
format allows the assessor much more flexibility to recognise and
analyse performance/ loss / waste aspects in order to identify the
efficiency and effectiveness of operations conducted. This format in
my opinion being viewed more valuable than electronic reporting
system can provide, where they are limited by the quality of data
input and the lack of metrics applied or that can be measure in the
first place? Using this simple format data can thus be more readily
modified, adapted to suit the assessor's needs.

If anyone wants further information on this please contact me.
[email protected]


Peter Aird, CEng.
Senior Drilling Specialist,
Maersk North Sea UK Ltd.

Is there any industry views on how performance and loss is measured
within organisations?
Documents uploaded by user:
3 answer(s)
Drilling Specialist/Well Engineer/Training Consultant
Total Posts: 339
Join Date: 10/01/05

NPT figures are correct. There is no missed or incorrect reporting.
- Data presents a 22day vs a 13day well. Same well design, same type
of rig, similar stratigraphy, both with low NPT but different
results. i.e. Object was to present differing loss/waste aspects of
two similar wells.

In response I would only like to emphasise that such simple yet
effective analysis of the daily drilling data as outlined is
necessary. i.e. to recognise and identify all performance/loss/waste
aspects of the well data.

Where yes, the 'devil unfortunately from my experience is contained
with the details and unfortunately where there are no silver bullets
or short cuts to be had w.r.t performance improvement or loss
reduction. Indeed having gone through 'technical limit challenges
several times. All I can state is that excellent well delivery is a
combination of the 100's of small detailed changes where the 'rig
hands' are generally the main contributors.

Standard NPT, WOW metrics etc. are also not what I am refering to or
what I really care about. i.e. We have been doing this for years,
with little improvements evident?. Metrics for me therefore needed to
and were changed. Its whats hideden is where the greatest
oipportunities lie? e.g. On the 13days well. There was neither NPT or
WOW, yet 25% of all operations were still identified as lost or

By implementing such opportunities one could then potentially deliver
a 11,0000ft North Sea exploration well in 10days. vs. 20days
currently acceptable with normal NPT/WOW/performance metrics applied?

A 10day and £2.5m+ per well difference would leave the results for
everyone to conclude for themselves, i.e. if detailed analysis does
benefits or not? Analysis I view not as 'addtional', but as an
absolute priority.


Myspread Users
Total Posts: 2
Join Date: 30/08/05
Dear Fellows,

Agree with the comments on time vrs depth tracking, it appears that
we are creating a new way to look at the same data set.

The figures quoted for the well - look incredibly low to me (6 hrs
Operational NPT) and 22hrs W.O.W. It looks as if there is some daily
reporting (miss coding) if 43% of the well is not being reported as
DT. either as NPT or WOW?

That aside efficiency of operations can be clearly seen by plotting a
technical limit line on the TVD vrsDays and cost data chart, however
one has to be carefull about what one is calling Technical Limit and
whether Weather is included, the amount of days routinely reported
etc. So it all comes down to the value, accuracy and coding used for
the input data.

We at Talisman run a daily updated performance tracker (excell
spreadsheet) which indicates Productive time, WOW and NPT on a per
phase/activity basis as well as the time depth chart- based on
planned versus actual, so why would we want to introduce a new
methodology or step to measuring this? Where is the advantage, we
can visually see where the problems are, and focus attention on those
areas / issues / particular phases - so I fail to see where this
additional operational monitoring requirement is taking us?

I look forward to your further explanation of the benefits of this
measurement procedure, as the "devil is always in the detail" rather
than statistics of course!


Managing Director (
Relentless Pursuit Of Perfection Ltd.
Total Posts: 376
Join Date: 10/01/05
Dear Business Associates

Better have a review of the [email protected] package DDR-1 where
Patrick attempts to do exactly what Peter Aird is on about.

In my early days from 1966 to 1973 with PetroFina/Angola, the use of
Time x depth curves - some 2 m x 1.5 m - was the best way to report
and to identify the non-productive time. These as the penetration
charts were prepared at the rig site with input from the crews.
Furthermore, those time x depth charts were always available both at
the office and at the site where the doers were plotting their
actuals x forecast.

This performance mirror is what we lack; I was unable to find a way
of doing that automatically in a scale that was wortwhile.

Best regards

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