Excel Pipes – GRP Experts Excel Pipes offers FARATEC ® GRP pipes for underground (uniaxial) and aboveground (biaxial) applications for transport of water, sewerage, and corrosive liquids. Joints and … Excel Pipes offers FARATEC ® GRP pipes for underground (uniaxial) and aboveground (biaxial) applications for transport of water, sewerage, and corrosive liquids. Joints and …