论文部分内容阅读
小眼井钻井、大斜度井和水平井钻井数量越来越多。在这类井中如何有效地向钻头施加钻压就成为人们普遍关注的问题。在转盘钻井和井下动力钻具钻井中一般都是靠钻柱重量向钻头施加钻压的。然而，在大斜度井和水平井钻井中，这种传统的加压方法存在一些缺陷：①由于钻柱重力在井眼方向的分量小或近似为零，很难满足预先设计的钻压；②由于钻柱自重对井壁的正压力大，因此增大管柱摩阻和转盘功率损失。摩阻问题又是制约大斜度井和水平井发展的重要因素之一。为此，研制了一种新型的利用钻井液压力为动力的加压装置———水力加压器。它可以平稳地对钻头施加钻压，可以减少钻头的振动传向水力加压器以上钻柱，减少钻铤和钻杆的疲劳破坏，可提高钻柱和钻头的使用寿命，降低钻井成本。现场试验表明其可靠性、安全性高，不仅能有效地解决大斜度井、水平井中钻压不易施加的问题，而且能较好地改变钻具受力。
Small-eye wells, high-deviated wells and horizontal wells are drilling more and more. How to effectively apply the weight-on-bit to drill in such wells has become a common concern. In rotary drilling and downhole power drill drilling is generally based on the weight of the drill string to drill bit pressure. However, this traditional pressurization method has some shortcomings in high-deviated and horizontal well drilling: ① It is difficult to meet the pre-designed weight-on-bit due to the small or near-zero component of the drill string gravity in the wellbore direction; ② due to the weight of the drill string on the wall of the positive pressure, thereby increasing the column friction and turntable power loss. The problem of friction resistance is one of the important factors restricting the development of high-deviated well and horizontal well. To this end, developed a new type of pressure using hydraulic drilling fluid pressure device --- hydraulic pressure. It can smoothly apply pressure on the drill bit, reducing the vibration of the drill bit to the drill string above the hydraulic accumulator, reducing the fatigue damage of the drill collar and the drill rod, improving the service life of the drill string and the drill bit, and reducing the drilling cost. Field tests show that its reliability and safety are high, which can not only effectively solve the problem that the weight-on-bit can not be easily applied in horizontal wells and horizontal wells, but also can change the stress of the drilling tools.