Well cement fluid loss additive and method

Patent · Tue Apr 23 04:00:00 EDT 1991

OSTI ID:5118370

Moran, L K; Murray, T R

This patent describes a method of cementing a casing in a wellbore. It comprises pumping a cement slurry into the annulus between the casing and the wellbore, the cement slurry containing from 0.2 to 2.0 percent by weight, based on the weight of cement solids in the slurry, of an additive consisting essentially of from 30 to 80 percent by weight of partially hydrolyzed high molecular weight vinyl acetate polymer, calcium sulfate in an amount equivalent to from 10 to 60 percent by weight of calcium sulfate hemihydrate, up to 5 percent by weight of a cross-linking compound for the polyvinyl acetate, and from 0 to 5 percent by weight of defoamer.

• Assignee: Conoco Inc., Ponca City, OK (USA)
• Patent Number(s): A; US 5009269
• Application Number: PPN: US 7-560533
• OSTI ID: 5118370
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
ACETATES
ADDITIVES
ALKALINE EARTH METAL COMPOUNDS
BUILDING MATERIALS
CALCIUM COMPOUNDS
CALCIUM SULFATES
CARBOXYLIC ACID SALTS
CEMENTING
CEMENTS
CHEMICAL COMPOSITION
LOSSES
MATERIALS
NATURAL GAS WELLS
OIL WELLS
ORGANIC COMPOUNDS
ORGANIC POLYMERS
OXYGEN COMPOUNDS
POLYMERS
POLYVINYLS
SULFATES
SULFUR COMPOUNDS
WELLS