深水铺管张紧器橡胶材料静摩擦行为研究

张紧器是深水油气管线铺设的核心装备之一,能够保证管线铺设过程中管道以平稳的速度及适中的张紧力水平下放入水中。张紧器上橡胶垫块与管道外壁受压接触,所产生的静摩擦力对维持管线受力平衡起到至关重要的作用。利用自制的试验装置,测试了不同试验载荷条件下橡胶材料与管道试样间的最大静摩擦力,并对接触区变形进行分析。试验结果表明,最大静摩擦力水平随法向载荷增大而上升,静摩擦因数则逐渐下降; 在同一法向载荷条件下,最大静摩擦力随切向载荷增长率的增加而波动; 接触系统静摩擦因数的波动受接触面间的粘性接触力水平与橡胶材料本身粘弹特性共同影响,而粘性接触力水平的作用占据首要位置。因此,在铺管过程中,应重点关注静摩擦因数随管道夹持力变化的规律,同时应选择合理的铺设速度,使静摩擦因数处于较小的波动范围内,防止发生脱管事故。

Static Friction Behaviors of Tensioner Rubber During Pipe Laying Operation

Tensioner is one of key instruments for deep water pipe laying operation,which keeps pipeline into sea water with stable velocity and suitable tension during the whole operation.The static friction is generated from the contact between rubber blocks which are fixed on the tensioner and the out wall of pipe,to maintain the increasing deadweight of the pipeline.In this study,a series of experimental investigations are carried out with self-built friction testing rig to reveal the static friction behaviors of rubber-pipe contact which is under different loading conditions.The results indicate that the maximum static friction of contact increases with normal load,whereas the coefficient of static friction decreases. The coefficient of static friction fluctuates with different increasing rate of tangential load. The fluctuation of coefficient of static friction is influenced by adhesion force of the contact system and the viscoelastic property of rubber material,and the adhesion factor contributes more remarkable.Therefore,it is important to take the accurate tendencyof coefficient of static friction into consideration during pipe laying operation,and select suitable velocity of pipeline to avoid the range of drastic fluctuation of the coefficient of static friction.