Chemical resistance and mechanical properties of glass fiber-reinforced plastic pipes for oil, gas, and power-plant applications

Glass fiber-reinforced plastic (GFRP) composite pipes are used in many diverse applications, including oil, gas, and power plants. These pipes are subjected to various harsh service conditions during their service life. The evaluation of mechanical properties and chemical resistance of these pipes is essential to assess their long-term performance in specific applications. The results of a study to evaluate the chemical resistance and mechanical properties of GFRP pipes for application in oil and gas plants are presented in this paper. Pipe specimens were preconditioned by filling them with 7.5% HCl, 8% H2SO4, and a mixture of 2% NaOH and 2% KMnO4 solutions maintained at 63°C. The preconditioned and fresh pipe specimens were exposed to clean and oily water [a mixture of 10% toluene, 10% kerosene, and 80% brine water (30 g/L NaCl)] maintained at 93°C and 1.5×106 Pa (15 bar) pressure for 1,000 h. The fresh, preconditioned, and exposed pipe specimens were tested to evaluate their axial and hoop tensile strength, water absorption, and loss on ignition. The experimental results did not exhibit major change in the properties of evaluated pipes owing to exposure to clean and oily water at high temperature and pressure. There was minimal or no loss in the axial and hoop strength of the preconditioned or exposed pipes. The absorption and loss of ignition did not increase significantly both due to pre-conditioning and evaluated exposure conditions. The results indicate that GFRP pipes are suitable for application in the oil and gas industry.