PIBSI对油基钻井液性能影响研究

常温条件下分别采用5号和3号两种白油配制基浆和油基钻井液体系,并在基浆和钻井液体系中加入不同质量分数的聚异丁烯丁二酰亚胺(PIBSI),考察不同温度下PIBSI的质量分数对基浆和钻井液体系流变、沉降和滤失性能的影响。结果表明,对于基浆而言,低温条件下(4℃)PIBSI能够提高基浆的沉降稳定性能,基浆的黏度随PIBSI质量分数的增加先降低后增加。对于油基钻井液体系而言,在适当质量分数下(5号白油体系PIBSI质量分数为2%,3号白油体系PIBSI质量分数为0.2%),PIBSI能够有效降低体系低温条件下(4℃)的黏度,而对室温(25℃)和高温(65℃)条件下体系的黏度、动切力等参数影响程度较小。PIBSI质量分数越高,两种油基钻井液体系的高温高压降滤失量越低。

Effect of PIBSI on the Properties of Oil-Based Drilling Fluid

5# mineral oil and 3# mineral oil were used separately to prepare the basic mud and the oil-based drilling fluid system at room temperature. PIBSI（polyisobutylene succinimide） with different concentration were added to investigate the effect on properties of the basic mud and oil-based drilling fluid system under different temperatures. The results showed that, PIBSI can improve sag stability and viscosity of the basic mud changes with the concentration of the PIBSI under low temperature（4 ℃ ）. As for oil-based drilling fluid system, PIBSI can decrease the viscosity of the system under low temperature while showed little effect on the viscosity and the gel strength under room and high temperatures if the concentration of PIBSI was in the appropriate concentration （for the 5# mineral oil based drilling system, the appropriate concentration was 2#, while for the 3# mineral oil based drilling system, the appropriate concentration was 0.2%）. The larger the concentrations of the PIBSI, the lower the HTHP filtration loss will be.