ANSI and API pumps

API pump is designed per API standard 610 for refinety and petrochemical applications or heavy duty users. Not like ANSI standard, API pump standards are written for many diJTcrent pump configurations. Most API pumps use closed impeller. Since most hydrocarbon service is not corrosive, the material selection of API pumps is much less comparing to that of the ANSI pumps. [1 ] 

In general API pumps cost more than ANSI pumps. 

---