Q&A No.720 - Failure to Get Casing, Liner or Screens to Depth

0 votes
Lasse Hermansson and Paul Newberry of Ridge AS in Norway are currently doing an evaluation of equipment and techniques to help deploy casing or liners, - and would be most appreciative if COIN members could take a few moments to give them their views on this issue:

In your experience, what would you consider the 5 most common causes of failure to get casing, reservoir liners or screens to depth in extended reach wells? We have a few suggestions but don’t let this limit your thoughts. All comments are welcome.

The suggested reasons are:

                • High tortuosity due to excessive geosteering

                • High tortuosity due to poor drilling BHA design

                • Poor formation characteristics, e.g. faults, boulders, unconsolidated formations

                • Ledges due to stringers

                • Wash-outs due to excessive circulating

                • Poor hole cleaning practices during drilling

                • Poor drilling fluid selection and design

                • Inadequate hole conditioning prior to running casing/liner

                • Poor fluid conditioning prior to running casing/liner

                • Taking too long between drilling the section and casing/liner running

                • To complex and stiff casing / liner / screen BHA components

                • Insufficient radial clearance for the hole conditions

                • Inability to rotate string

                • Poor operating practices during casing/liner running

                • Poor running string design
asked Mar 17, 2017 in COIN by Fiona Curley (1,480 points)

2 Answers

0 votes
  • instable shales collapsing
  • poor running string design - leaving insufficient weight to setdown effectively while pushing screens into open hole - have used rollerblade centrialisers on workstring to reduce drag inside casing
  • inability to rotate string - have not seen problems yet but if drag charts show issues, consider use of clutch based swivel above running tool (Swivelmaster or similar) - has been applied in shallow wells with large stepout 
  • inability to circulate through bottom of BHA if you do not have washdown capability - not every lower completion/screen bha design has washdown shoe with washpipe stung in, can make the difference in getting through tight spot
  • omittance of check trip from shoe to TD with drilling BHA prior to pulling out of hole - final check to simulate if you can slide in with BHA with pumps off to check for any tight spots before commiting to POOH and making up screens/liner
  • strength of screens - mechanical limitation of screens before damage will dictate max allowable applied setdown weight, for direct wraps much higher compared to any slip-on cartridge/jacket slip-on type as weld on end rings typically order of magnitude lower
answered Mar 20, 2017 by Aart van Kranenburg (180 points)
Aart,  Many thanks for taking the time to respond to Lasse and Paul's query..
Kind regards,
0 votes

Yes many thanks for your answers, great to hear from you again

answered Mar 20, 2017 by Paul Newberry (140 points)