Research On Nanometer Blocking Technology For Drilling Fluid

During drilling,especially during shale drilling,a major problem that plagues smooth drilling is instability of the borehole wall.Shale is rich in nanometer-sized pores and fractures.How to block these nanometer pores and prevent drilling? In the process,drilling fluid or drilling filtrate enters the formation through these tiny holes to prevent damage to the formation caused by hydration or capillary force,and then to prevent the collapse of the well wall is the fundamental solution to the problem of well wall stability.At present,many nanometer plugging materials have been researched at home and abroad for plugging pores of nanometer level in the formation,and there are many evaluation methods about nanometer plugging materials.On the basis of comparing the plugging evaluation methods at home and abroad,Utilizing laboratory-developed nanomaterials through medium-pressure dehydration experiments,high-temperature and high-pressure experiments,laboratory-developed pressure transfer experiments,and observation of microscopic changes through scanning electron microscopy,and other experimental methods,a practical and economical set of nanometer-pore seals was finally established.Evaluation method.In the previous experiments and on-site conditions,one of the most important reasons for the instability of water-sensitive borehole walls was that drilling mud caused water loss through the borehole wall under the effect of drilling pressure.Through daily experiments,it is found that there is a certain pattern of this type of water loss.In this paper,by setting different mud pressures,a series of experimental studies on water loss under different mud pressures have been conducted.The final experimental results show that the amount of mud loss is at the same time.The internal pressure decreases first and then increases as the pressure increases.As the pressure on the mud increases,the proportion of water loss in the early stage gradually increases.The quality of the mud cake obtained in the experiment increases linearly with the increase in pressure,and the standard water loss increases.As the mass of mud cake increases,the amount decreases first and then increases.