公开(公告)号：US2198401A

公开(公告)日：1940-04-23

申请号：US27444739

申请日：1939-05-18

申请人： JAMES W JENNINGS

发明人： ALLSTON HUGH C

IPC分类号： F04F5/14

CPC分类号： F04F5/14

公开(公告)号：US5464058A

公开(公告)日：1995-11-07

申请号：US405736

申请日：1995-03-17

申请人： James N. McCoy ,  Augusto L. Podio ,  James W. Jennings

发明人： James N. McCoy ,  Augusto L. Podio ,  James W. Jennings

IPC分类号： E21B47/00 ,  F04B47/02 ,  G01B7/12 ,  G01B7/16 ,  G01L5/00

CPC分类号： F04B47/02 ,  E21B47/0008 ,  G01B7/12 ,  G01B7/16 ,  G01L5/0061 ,  F04B2201/121

摘要： In a pumping well, oil is normally lifted to the surface by a rod which extends from the surface to a downhole pump. A transducer is attached to the rod at the surface to sense the deformation, i.e., the change in diameter or circumference of the rod to determine change in rod loading. The transducer includes strain gauges which produce output signals proportional to the change in the diameter or circumference of the rod which occurs due to changes in load on the rod. The transducer may also include an accelerometer. The change in load on the polished rod over a pump cycle is used in conjunction with data produced by the accelerometer to calculate a downhole card. The downhole card showing change in pump load is adjusted to reflect absolute rod load by determining an appropriate offset. Various ways to determine the offset are available. Since the pump plunger load is zero on the downstroke when the traveling valve is open, the value necessary to correct the calculated minimum pump value to a zero load condition may be used as the offset. The offset can also be estimated by either a calculation of the rod weight, a predetermined rod weight measurement or an estimated load value by the operator.

摘要翻译： 在抽油井中，油通常通过从表面延伸到井下泵的杆将其提升到表面。 传感器在表面处连接到杆上以感测变形，即杆的直径或圆周的变化，以确定杆负载的变化。 换能器包括应变计，其产生与杆的直径或圆周的变化成比例的输出信号，其由于杆上的负载变化而发生。 换能器还可以包括加速度计。 泵循环上抛光棒上的负载变化与加速度计产生的数据结合使用，以计算井下卡。 通过确定适当的偏移，调整显示泵载荷变化的井下卡，以反映绝对的杆载荷。 可以使用各种确定偏移量的方法。 由于在行程阀打开时，下冲程中的泵柱塞负载为零，所以将计算出的最小泵值修正为零负载条件所需的值可以用作偏移量。 偏移量也可以通过计算杆重量，预定的杆重量测量值或操作者的估计负载值来估计。