Design of Composite Pipes with Different Fiber Orientations Evaluation of the Internal Pressure Capacity

Fiber reinforced composites pipes provide excellent strength and stiffness characteristics and high corrosion and erosion resistance. In addition, the possibility to tailor the strength and stiffness characteristics by optimizing the winding angle gives the designer extra flexibility to design different pipe based on the different working conditions. In the current work, GFRP pipe designed with four different winding angles have been tested under internal pressure. Four pipes were manufactured by filament winding with winding angles of [±45/ ±45/ ±45], [±55/ ±55/ ±55], [±63/ ±63/ ±63], and [±63/ ±45/ ±55]. Each pipe has internal diameter of 110 mm, wall-thickness of 3.8 mm, and length of 450 mm. The pipes were exposed to internal pressure to determine their capacities. Under internal pressure, the maximum failure pressure recorded (60 bar) was that for the pipes with [±55]3 winding angles. All specimens failed in the same way of initial leakage, governed by matrix cracking, which causes a drop in the internal pressure. Keywords—Composite, Pipe, Winding angle, Internal pressure