管线上卷极限弯矩分析

The limit moment analysis of reeling-on pipeline

利用弹塑性理论对卷管施加弯矩载荷时的截面屈服过程进行了理论分析,得出了卷管上卷时卷管所能承受的极限弯矩;通过实例分析得出X65钢在发生塑性应变为2.5%时的卷管两端截面夹角为1.98rad、滚筒直径为5.05m、极限弯矩为99.2kN m。根据DNV-OS-F101和API-RP-1111的相关规定,可将99.2kN m界定为对卷管施加弯矩的上限值;卷管弯矩上限值对应卷管上卷时的滚筒直径上限值,表明卷管上卷时可通过滚筒直径来限制卷管弯矩值。本文结果可为深水管线卷轴铺设的应用提供理论依据。

Plastic strain deformation exists on pipelines during the reel-lay progress.In order to ensure the safe plastic strain deformation before entering into water,bending moment of the reel pipe must be controlled.Bending moment formula derivation on different bending periods is conducted with the help of elastic-plastic theory in the paper.When plastic strain of X65 steel is 2.5%,the maximum value of bending moment is worked out through example calculation,equals to 99.2kN.m.And higher limit of bending moment is reasonably proposed,which provides a theory basis for the application of reel-lay technique in deep water.