Through the analysis for the process of Walsh modulation and demodula tion,the adaptive error-limiting method suitable for the Walsh code shutting multiplex ing in the mine monitor system is advanced in this article. ...Through the analysis for the process of Walsh modulation and demodula tion,the adaptive error-limiting method suitable for the Walsh code shutting multiplex ing in the mine monitor system is advanced in this article. It is proved by theoretical analysis and circuit experiments that this method is easy to carry out and can not only improve the quality of information transmission but also meet the requirement of the system patrol test time without the increasement of system investment.展开更多
The concern on formation damage control of high permeability sandstone reservoir has been growing in oil industry in recent years. The invasion of particles and the filtrate of drilling fluid are proven as one of the ...The concern on formation damage control of high permeability sandstone reservoir has been growing in oil industry in recent years. The invasion of particles and the filtrate of drilling fluid are proven as one of the key factors accounting for reservoir damage. Based on the ideal packing theory, the practical software has been developed to optimize the blending proportion of several bridging agents, and the core flooding tests were conducted to evaluate return permeability of core samples contaminated with different drilling fluids. Experimental results show that the ideal packing approach can reduce the dynamic filtration rate, improve the return permeability and drawdown the breakthrough pressure, indicating that this kind of drilling fluids can meet the demands of formation damage control for high permeability sandstone reservoirs. Some applying procedures for formation damage control are also proposed in this paper.展开更多
文摘Through the analysis for the process of Walsh modulation and demodula tion,the adaptive error-limiting method suitable for the Walsh code shutting multiplex ing in the mine monitor system is advanced in this article. It is proved by theoretical analysis and circuit experiments that this method is easy to carry out and can not only improve the quality of information transmission but also meet the requirement of the system patrol test time without the increasement of system investment.
文摘The concern on formation damage control of high permeability sandstone reservoir has been growing in oil industry in recent years. The invasion of particles and the filtrate of drilling fluid are proven as one of the key factors accounting for reservoir damage. Based on the ideal packing theory, the practical software has been developed to optimize the blending proportion of several bridging agents, and the core flooding tests were conducted to evaluate return permeability of core samples contaminated with different drilling fluids. Experimental results show that the ideal packing approach can reduce the dynamic filtration rate, improve the return permeability and drawdown the breakthrough pressure, indicating that this kind of drilling fluids can meet the demands of formation damage control for high permeability sandstone reservoirs. Some applying procedures for formation damage control are also proposed in this paper.
