Piping design creates the three-dimensional layouts, component specifications, and engineering documentation for piping systems connecting process equipment, utilities, and facilities. Effective design optimizes flow performance, installation cost, and operational reliability while meeting code requirements and project constraints.

Design process includes pipe sizing based on flow rates and allowable pressure drop, layout development routing pipes efficiently while maintaining accessibility, stress analysis ensuring flexibility for thermal expansion, support design for deadweight and dynamic loads, component selection including valves and specialties, and material specification for service conditions.

Design codes—ASME B31.1 for power piping, B31.3 for process piping, others for specific applications—govern design requirements including allowable stresses, minimum wall thickness, fabrication standards, and examination requirements. Compliance ensures piping safely contains design pressures and temperatures.

Layout considerations balance competing objectives: minimizing pipe length and fittings to reduce cost and pressure drop, providing access for equipment maintenance and piping inspection, accommodating thermal expansion without excessive stresses, meeting plot space constraints, and enabling constructability through accessible welding and reasonable spool lengths.