关键词: 溶解氧, 钻具腐蚀, 除氧剂, 缓蚀剂, 配伍, 集输系统

Abstract: Focusing on corrosion of drilling tools caused by the combined effects of CT and dissolved oxygen from the brine drilling fluid system used in Shell Changbei Block, CQ-ACAP well preservatives for oil wells are developed indoors, which include oxygen scavengers (G713-CY) used for oil and gas fields and drilling fluid inhibitor (G709-ZHY). These two products can be directly added into drilling fluid according to the proportions to suppress corrosion of drilling tools while removing dissolve oxygen. Dynamic cycle oxygen-removing rate reaches 99 percent. The dissolve oxygen content of the system can be reduced to 0. 1 mg/ L in one hour. The “zero oxygen” effect can last 72 hours. Dynamic corrosion inhibiting rare is higher than 88 percent. The products are obviously superior in technology, price and environmental protection as compared to the same products both at home and abroad. They have been continuously used in Shell Changbei Block for six years, showing a good compatibility with Shell brine drilling fluid system. Meanwhile, they can suppress pitting corrosion and erosion and effectively protect drilling tools to extend their service life, significantly reducing production cost. These products can be also used in the water injection manifolds of oilfields, gathering systems and complex annular protection fluid, thus having a broad market prospect for application.