By dividing the rewinding process of a three-roll rewinder into three zones, mathematical equations were formulated and diagrams were drawn to determine the structure factors of the rewinder, such as the diameters and...By dividing the rewinding process of a three-roll rewinder into three zones, mathematical equations were formulated and diagrams were drawn to determine the structure factors of the rewinder, such as the diameters and spatial distribution of the rewinding rolls. The qualitative and quantitative analysis results show that the roll gap of the first two rewinding rolls and the angle between the line that connects the center points of the first two rewinding rolls and the vertical line play an important role in determining the ideal log diameter, which is related to the production capacity of the rewinder. Additionally, the ideal roll gap has a significant effect on the spatial distribution of the three rewinding rolls, the rewinding dead zone, and the rewinding quality of the log, which should be taken into full consideration when designing and improving rewinders to enhance production efficiency and satisfy ultra-high quality requirements.展开更多
Natural carbonate core samples with artificial fractures are often used to evaluate the damage of fractured carbonate formations in the laboratory. It is shown that the most frequent error for evaluation results direc...Natural carbonate core samples with artificial fractures are often used to evaluate the damage of fractured carbonate formations in the laboratory. It is shown that the most frequent error for evaluation results directly from the random width characterized by the artificial fractures. To solve this problem, a series of simulated fractured core samples made of stainless steel with a given width of fracture were prepared. The relative error for the width of artificial fracture decreased to 1%. The width of natural and artificial fractures in carbonate reservoirs can be estimated by image log data. A series of tests for formation damage were conducted by using the stainless steel simulated core samples flushed with different drilling fluids, such as the sulfonate/polymer drill-in fluid and the solids-flee drill-in fluid with or without ideal packing bridging materials. Based on the experimental results using this kind of simulated cores, a novel approach to the damage control of fractured carbonate reservoirs was presented. The effective temporary plugging ring on the end face of the simulated core sample can be observed clearly. The experimental results also show that the stainless steel simulated cores made it possible to visualize the solids and filtrate invasion.展开更多
文摘By dividing the rewinding process of a three-roll rewinder into three zones, mathematical equations were formulated and diagrams were drawn to determine the structure factors of the rewinder, such as the diameters and spatial distribution of the rewinding rolls. The qualitative and quantitative analysis results show that the roll gap of the first two rewinding rolls and the angle between the line that connects the center points of the first two rewinding rolls and the vertical line play an important role in determining the ideal log diameter, which is related to the production capacity of the rewinder. Additionally, the ideal roll gap has a significant effect on the spatial distribution of the three rewinding rolls, the rewinding dead zone, and the rewinding quality of the log, which should be taken into full consideration when designing and improving rewinders to enhance production efficiency and satisfy ultra-high quality requirements.
文摘Natural carbonate core samples with artificial fractures are often used to evaluate the damage of fractured carbonate formations in the laboratory. It is shown that the most frequent error for evaluation results directly from the random width characterized by the artificial fractures. To solve this problem, a series of simulated fractured core samples made of stainless steel with a given width of fracture were prepared. The relative error for the width of artificial fracture decreased to 1%. The width of natural and artificial fractures in carbonate reservoirs can be estimated by image log data. A series of tests for formation damage were conducted by using the stainless steel simulated core samples flushed with different drilling fluids, such as the sulfonate/polymer drill-in fluid and the solids-flee drill-in fluid with or without ideal packing bridging materials. Based on the experimental results using this kind of simulated cores, a novel approach to the damage control of fractured carbonate reservoirs was presented. The effective temporary plugging ring on the end face of the simulated core sample can be observed clearly. The experimental results also show that the stainless steel simulated cores made it possible to visualize the solids and filtrate invasion.
