连续管夹持力学特性研究  

Study on Mechanical Properties of Coiled Tubing under Clamping State

作　　者：胡志强[1] 杨高[1] 刘菲[1] 张富强[1] 颜家福[1] 刘平国[1] 

机构地区：[1]中国石油集团钻井工程技术研究院江汉机械研究所

出　　处：《石油机械》2016年第11期89-93,共5页China Petroleum Machinery

基　　金：国家科技重大专项"致密油气连续管侧钻钻井技术与装备"(2016ZX05022003)

摘　　要：研究连续管夹持状态下的力学特性,对夹持块设计和优化,确定最优夹紧压力等具有重要意义。建立了夹持块-连续管系统力学模型,分析了连续管在夹持状态下内部应力和表面正压力分布规律,探讨了连续管夹持椭圆系数和壁厚对连续管夹持力学特性的影响。研究结果表明:连续管与夹持块之间的正压力随夹持椭圆系数增大而增大,接触面积随夹持椭圆系数的绝对值增大而减小;当夹持椭圆系数大于3.2%时,需要调整夹紧压力或更换夹持块来避免连续管表面受损;夹持椭圆系数为0.8%时,连续管应力最小,且表面正压力较大;壁厚越大的连续管,夹持椭圆系数对其夹持力学特性的影响越大。研究结果对夹持块设计优化、确定夹紧压力以及提高注入头可靠性等具有积极意义。Analyzing mechanical properties of coiled tubing under clamping state are important for design and optimization of clamping block and determination of optimal clamping pressure. In this paper,a mechanical model was built for the clamping block-coiled tubing system to analyze the distribution pattern of internal stress and surface positive pressure of the coiled tubing under clamping state. Then,the effects of coiled tubing clamping ellipse coefficient and wall thickness on mechanical properties of the coiled tubing under clamping state were discussed. The study results indicate that the positive pressure between the coiled tubing and the clamping block rises with increase of clamping ellipse coefficient,and the contact area decreases with absolute value of ellipse coefficient increasing. If the clamping ellipse coefficient exceeds 3. 2%,surface damage of the coiled tubing can be avoided by adjusting the clamping pressure or replacing the clamping block. If the clamping ellipse coefficient is 0. 8%,the coiled tubing would be subject to minimum stress and the larger surface positive pressure. Effects of the ellipse coefficient on mechanical properties of clamping rise with increase of the wall thickness. The results are of positive significance on clamping block design optimization,clamping pressure determination and injection head reliability improvement.

关 键 词：连续管 夹持力学特性 夹持椭圆系数 壁厚 表面正压力 有限元 

分 类 号：TE921[石油与天然气工程—石油机械设备]