Preparation Of The Internal Coating For Natural Gas Pipeline And Research On Its Drag-reduction Performance

Pipeline is the major way of natural gas transportation. Reducing the frictional resistance in the process of pipeline transportation is an important method to raise the transportation efficiency. In this paper, Silane coupling agent KH-560and titanate coupling agent DN-102were adopted to modify the pigment fine iron oxide red (Fe3O4) powder to improve the dispersing performance of the powder in the organic system. The solvent-free epoxy coating for long distance natural gas pipeline was prepared and the performance of coatings was studied. The physical properties of coating specimens such as adhesive force, abrasive resistance, and bending property were tested, and the anti-corrosion performance was researched by Electrochemical Impedance Spectroscopy. Then a drag-reduction evaluation device was designed and established according to the flow states similarity principle and the drag-reduction performance of coating was tested.The experiment results indicated that the comprehensive performance of fine iron oxide red modified by1.5%titanate coupling agent DN-102was outstanding. The lipophilic degree was improved, the dispersion of Fe3O4powder was also enhanced in coating system The physical properties of solvent-free epoxy coating met the standards of natural gas pipeline internal coating. In order to optimize drag reduction property of the coating, this paper employ orthogonal method to design the drag reduction coating formulations for long distance natural gas pipeline, and optimum coating formulations in the end. For the optimized formula, in the experimental range, when Reynolds number of pipes reached complete turbulence zone, the drag-reduction rate of the coating was up to28.57%, and the throughput increased by17.14%.