Title:
DRILLING FLUIDS
Document Type and Number:
WIPO Patent Application WO/2011/092491
Kind Code:
A3
Abstract:
An additive for a water-based mud drilling fluid or for drill-in fluids comprises a 0.5wt% solution of 87-89 mole% hydrolysed polyvinylalcohol, having a weight average molecular weight of about 20,000. Use of the additive may reduce susceptibility of a wellbore to blockages, reduce accumulation of accretions between a drill string and wellbore casing, reduce bit-balling and facilitate separation of undesirable insoluble solids from a drilling fluid returned to the surface.
Inventors:
FLETCHER PHILIP (GB)
CRABTREE MICHAEL JOHN (GB)
FORSYTH JEFFREY (GB)
CRABTREE MICHAEL JOHN (GB)
FORSYTH JEFFREY (GB)
Application Number:
PCT/GB2011/050115
Publication Date:
October 06, 2011
Filing Date:
January 25, 2011
Export Citation:
Assignee:
OILFLOW SOLUTIONS HOLDINGS LTD (GB)
FLETCHER PHILIP (GB)
CRABTREE MICHAEL JOHN (GB)
FORSYTH JEFFREY (GB)
FLETCHER PHILIP (GB)
CRABTREE MICHAEL JOHN (GB)
FORSYTH JEFFREY (GB)
International Classes:
C09K8/035; F02P7/02
Domestic Patent References:
| WO2008152357A1 | 2008-12-18 |
Foreign References:
| US20060157248A1 | 2006-07-20 | |||
| US3872018A | 1975-03-18 | |||
| US20090149354A1 | 2009-06-11 |
Attorney, Agent or Firm:
BRIERLEY, Anthony Paul (15 Clare RoadHalifax, West Yorkshire HX1 2HY, GB)
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