Effect of Material Type and Size Distribution on Performance of Loss/Seepage Control Material

Abstract

Abstract Circulation losses have always been a serious and expensive problem to drilling industry. Even with the best drilling practices circulation losses do occur. In order to reduce such losses to acceptable level fluid Loss Control Material (LCM) or Seepage Control Material (SCM) is used. The objectives of this study have been to evaluate and compare the performance of different LCM/SCM and determine the effect of size distribution on their performance. Twenty-four different LCM/SCM samples made of various materials and blends of material having different size distributions were tested with three different types of mud. The three mud types used were water base mud, regular oil base mud, and environmentally safe oil base (Synvert) mud. With each mud three tests were conducted, one with the base mud and two with LCM/SCM concentrations of 5 and 10 lbs/bbl. The experiments were conducted in a Permeability Plugging Apparatus (PPA) at a differential pressure of 2500 psi and 250 °F, using ceramic disks. The performance of each LCM/SCM sample was determined based on the amount of spurt loss and total fluid loss of the mud according to the recommended procedure for PPA. The experiments show that amount of fluid loss depends on the mud type, LCM/SCM material, concentration and size distribution. This paper presents details of the experiments, the collected data and the analysis and discussion of the results obtained.