Improving the Cuttings Transport Performance of Water-based Mud Through the Use of Polypropylene Beads

This research work presents the experimental results of the effect of polypropylene beads' concentrations in waterbased mud on wellbore cleaning.A comparative study of cuttings transport performance (CTP) of water-based mud and water-based mud with polypropylene beads were carried out at different hole angles of 0°, 30°, 60°.75° and 90° in a 13 ft (3.96 m) acrylic concentric annulus flow test section, having a 2 in (50.8 mm) casing ID and a fixed 0.79 in (20 mm) inner pipe OD.A total of 100 runs had been accomplished using fine sands (from Tanjung Balau, Johor Bahru, Malaysia), of size ranging from 5/127 -6/127" (1.0 -1.2 mm) and density 2.4 g/cc (2400 kg/m 3 ), with the mud density and viscosity maintained at 9 ppg (1078 kg/m 3 ) and 5 cp (0.005 Pa.s), respectively, in a flow velocity of 2.1 ft/s (0.64 m/s).Polypropylene beads used in this study have the following properties: 290 kg/cm 2 of tensile strength at yield, 0.86 g/cc (860 kg/m 3 ) density, 4 mm (20/127") size, 82 R scale Rockwell hardness, 13,500 kg/cm 2 flexural modulus, 85°C heat deflection temperature at 4.6 kg/cm 2 , 4 g/10 min melt flow rate at 230°C and spherical in shape.The experimental findings showed that commingling the basic mud with polypropylene beads has successfully introduced a buoyant force which was found to have improved the cuttings transport performance by more than 10% when weight concentration of the polypropylene beads was increased to 1.5% as compared with the performance obtained from the basic water-based mud.The improvement of cuttings transport performance was found to be more significant in a vertical hole.