Piping designers always want higher allowable nozzle loads to simplify pump piping designs, while pump manufacturers want smaller such loads to assure good alignment, higher reliability and fewer problems in operation. With long-term reliability a key factor, Amin Almasi recommends that users side with the manufacturer. The use of some common practices for general plant piping could lead to real problems in pump piping arrangements. In a pump system under ambient conditions, the dead weight of the piping should be entirely absorbed by suitable supports. Only nozzle loads induced by temperature, pressure and the transported medium (or similar operational loads) at the operating conditions can be compensated for by pre-stressing (or springing) the pipes. In this article, pump nozzle load limits, proper load optimization and correct pump piping are discussed.
展开▼
