Research And Application On Perforators With High Shot Density And Deep Penetration

Perforation completion is the main means of establishing oil gas channel betweenreservoir and wellbore. If perforation effect is not so well, oil and gas productivity is notaccurate, which results in wrong decision-making and economic loss. Perforation effect ismainly related to perforating depth, size, density of the perforator,and so on. Usually deeperperforating depth, larger diameter, higher density, perforating effect is better, but theperforators with high density perforate shallow depth.Offshore oil and gas wells drilled inwestern South China Sea are mainly used OD177.8mm casing for completion,and OD127mm perforator for perforating.Two types of127perforators with high density or deeppenetration now are in common use, the former perforates too shallow deep, the latterperforates too low density, so there is no perforator with both characteristics of high densityand deep penetration to be used. Present perforators can satisfy basically the oil gas filedswith high porosity and permeability.But with the increase of exploration extent, many lowporosity and permeability reservoirs are discovered. The perforators are hard to be consideredboth high density and deep penetration, so deliverability of deeply contaminated reservoirsbeing perforated by high density perforators and low porosity-permeability reservoirs beingperforated by deep penetration perforators sometimes is not true,which leads to erroneousjudgement to reservoirs and economic loss from repeated testing, and is not conducive tomaintaining and development of oil-gas wells.Therefore, researching and developing theperforators combining high density and deep penetration has an important significance. Thecritical point is how to prevent charge interference and improve perforating depth. In thispaper, it uses the mature software and theory, develop designing methods about a set ofperfect high density and deep penetration. First, perforation optimization software and chargeinterference prevention theory are utilized to improve the high density and depth perforatinggun design theory, overall structure and determine the shape of the perforating gun charge.And focuses on the charge, analyze the influencing factors of charge from shaped charge jetforming and penetration theory. Use the numerical simulation software to design the shapedcharge liner material formula, structure, and finally optimize the charge internal structure.Using X-ray flash photography, orthogonal experiments to conduct perforatingexperiments, and choose the optimized charge design. And finally, conduct concrete targetperforation experiments according the API RP19B standards to verify that the perforator hasthe great performance.The perforator is used in WZ6-8-3well testing, achieved good results.Research and development of the perforator has filled up the blank of domestic and foreignperforators, the design method has important significance to improve national design level ofperforator.