公开(公告)号：WO2013063591A2

公开(公告)日：2013-05-02

申请号：PCT/US2012/062459

申请日：2012-10-29

Applicant: WEATHERFORD/LAMB, INC. ,  PONS, Victoria, M.

Inventor： PONS, Victoria, M.

IPC: E21B43/00 ,  E21B43/12

CPC classification number: F04B49/065 ,  E21B43/127 ,  E21B47/0008 ,  E21B2043/125 ,  F04B47/022 ,  F04B49/20 ,  F04B51/00 ,  F04B2201/121 ,  F04B2201/1211 ,  G05B13/042

Abstract: Diagnosing a pump apparatus having a downhole pump disposed in a deviated wellbore characterizes axial and transverse displacement of a rod string with two coupled non-linear differential equations of fourth order, which include axial and transverse equations of motion. To solve the equations, derivatives are replaced with finite difference analogs. Initial axial displacement of the rod string is calculated by assuming there is no transverse displacement and solving the axial equation. Initial axial force is calculated using the initial axial displacement and assuming there is no transverse displacement. Initial transverse displacement is calculated using the initial axial force and the initial axial displacement. Axial force and friction force are calculated using the initial displacements, and the axial displacement at the downhole pump is calculated by solving the axial equation with the axial force and the friction force. Load at the downhole pump is calculated so a downhole card can be generated.

Abstract translation: 诊断具有设置在偏斜井筒中的井下泵的泵装置表征具有四次的两个耦合非线性微分方程的杆串的轴向和横向位移，其包括轴向和横向运动方程。 为了求解方程，导数被有限差分类似物代替。 通过假设没有横向位移并求解轴向方程来计算杆柱的初始轴向位移。 使用初始轴向位移计算初始轴向力，假设没有横向位移。 使用初始轴向力和初始轴向位移计算初始横向位移。 使用初始位移计算轴向力和摩擦力，并通过轴向力和摩擦力求解轴向方程来计算井下泵的轴向位移。 计算井下泵的负荷，因此可以产生井下卡。