National Pump has a complete line of API-610 type VS-0 submersible, VS-1 sump, and VS-6 canned vertical turbine pumps for the Petroleum market conforming to the latest edition of the API-610 standard. Applications include:
Does National Pump stock Stainless Steel impellers?
Yes, National Pump stocks both 304 & 316 grade stainless steel impellers, up through 15” designs with NO performance corrections.
What is NPSHR (Net Positive Suction Head Required) mean on the performance curve?
NPSHR is the minimum pressure required at the first impeller of the pump to keep the pump from cavitating (i.e. turning water to water vapor in the pump). This differs from NPSHA (available) which is the absolute pressure at the pump suction. Both values are represented in ‘feet’ of pressure. NPSHA must be a minimum of 3 feet more than NPSHR.