Study On Oil In Water Foam Drilling Fluid With Low Density And Anti-temperature Properties

The paper reports the properties and existing problems of the oil in water foam drilling fluids . According to the geologic properties of sandstone reservoir and the base fluid is composed by the mineral oil and water. In terms of the assessment of drilling fluids treating agent. The paper select the emulsifying agent with good anti-temperature property and emulsion ability. The compound foaming agent with approved foamability and one kind of peculiar polymer surface acting agent as stabilizer are slected. In terms of the assessment of analysis stability, the paper select the fluid loss agent with good anti-temperature property and fluid loss property. The oil in water foam drilling fluid with low density and anti temperature properties is based on it above.The laboratory experiment verify the kind of foam drilling fluids is up to 150℃. The foma drilling fluids has good rheological properties, good emulsion stability and good oiliness. The foma drilling fluids has lower filter loss, water loss in medium pressure less than or equal to 5ml and the water loss in high temperature and pressure less than or equal to 15ml.It accomplishes the drilling in lower density(0.55-0.85 g·cm-3).The foam drilling fluids has good abilities to resist salt, calcium and crude petroleum.The system can adapt to the production need.In terms of foam microscopic structure characteristic analysis to the foam drilling fluids.The non-accumulation foam has guaranteed the system stability.