How to start a centrifugal pump with opened discharge valve??

[sunny_ahanwu]

Use, here You have a great diference blecaute the circuito is pressurized, só the centrifugas pump have a compressivos pressure and the pump can status without valve because the pump flor is determinated by This pressure

Thanks for your reply.
In API 610 11th, clause 7.1.6,"Some pumps are equipped with bypasses, in which case alternative starting conditons should be used", what does it mean? It means to start the pump with VFD??