fax 01-972-952-9435. AbstractWith surface measurements alone, liner cementing operations are difficult to interpret because of the dampening effects of the mud and greater overlaying pressure events such as cement free fall. In April 2001, an operator in the North Sea started to use downhole memory pressure gauges in the liner running string to gather pressure data for evaluation of liner equipment performance and cement placement. The collected data has shown downhole pressure effects that have not been seen with surface pressure measurements. This data also allows comparison of actual and simulated downhole pressure, which can improve cement job simulations.