...R. Kyle Chambliss; James Christian Cox; James F. Lea A theoretical calculation is needed to predict pump slippage in a rod pumped well. Slippage lubricates the pump plunger and barrel and prevents galling of metals. Additionally, an estimate of plunger slippage is necessary to calculate pump...

...Jose´ W. Vanegas Prada; Antonio C. Bannwart The use of core-annular flow pattern may be attractive as an artificial lift method in heavy oil wells. This flow pattern can be induced by the lateral injection of relatively small quantities of water, in order to get a lubricated oil core along the pipe...