... the gaseous liquid column at the bottom of the well. Processing this acoustic signal allows the depth and fall velocity of the falling plunger to be determined. Fig. 1 shows the plunger-fall velocity decreasing smoothly as a function of time. Although there seems to be some scatter of velocities...

... annulus areas at various pressures. The gradient correction factor indicates the amount of liquid present in a gaseous liquid column compared with a completely liquid column. This curve was prepared by W. E. Gilbert and is presented in Ref. 1. Application of Gilbert's Curve to Producing Oil Wells When...