Piping Systems are closed tubular arrangements that move gases, liquids, and solids (as slurries) through industrial processes (especially in refining); to users (distribution of natural gas, oil, and water); and from users back to treatment (sewage). Piping systems include compressors and pumps to keep material moving, valves to control and direct flows, and sensors to track volumes/deliveries. Engineering concerns in piping systems are materials, safety, security, and seismic risks.ping Systems are closed tubular arrangements that move gases, liquids, and solids (as slurries) through industrial processes (especially in refining); to users (distribution of natural gas, oil, and water); and from users back to treatment (sewage). Piping systems include compressors and pumps to keep material moving, valves to control and direct flows, and sensors to track volumes/deliveries. Engineering concerns in piping systems are materials, safety, security, and seismic risks.