Index Line

25 November 2014 Hi Guys,

Been cracking my head over how to use the index line. I'm referring to the index line on floaters where the line is tied to the lower telescopic joint of the riser which is used to check for string land outs.

1. How is the index line first established? How do we use it thereafter?
2. I have the following measured data from the toolpusher:-
   a) Datum (Wellhead) to Index Line = 1271.12m
   b) Index line to upper drill pipe tool joint = 1.89m
   c) Datum to hanger setting depth = 1.21m
   d) Upper tool joint as per pipe tally = 1274.145m
   

With these numbers he tells me we are "off" by
1271.12 + 1.89 + 1.21 - 1274.145
=0.075m.

Is these calculations correct? So does it mean we are above or lower by 0.075m?

My own thoughts is that we can measure RKB to index line at the start and then when we measure it again, we just add/subtract the difference to correct for tide. Could it be done that way too?

Really appreciate the help.
Sam

4 Answer(s)

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