API 610 (Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas Industries)
API 610 is the American Petroleum Institute standard governing centrifugal pumps in petroleum, petrochemical, and natural gas service. It defines pump types by configuration (OH overhung, BB between-bearings, VS vertical-suspended, SP submersible), minimum design and construction requirements, allowable operating regions on the pump curve, materials of construction selection rules, vibration and bearing temperature limits, and the datasheet form used to specify pumps. The current edition is API 610 12th edition (2021); ISO 13709 is the identical international version.
What pump types does API 610 cover?.
API 610 defines five major pump-type families. OH (overhung) pumps mount the impeller on an extended shaft with no support bearing between the impeller and the driver; OH1 is foot-mounted, OH2 is centerline-mounted, OH3 is vertical inline. BB (between-bearings) pumps support the rotor between two radial bearings; BB1 is axially split single-stage, BB2 is radially split single-stage, BB3 and BB4 are multi-stage between-bearings, BB5 is barrel-cased multi-stage. VS (vertical-suspended) pumps hang from a discharge head over a sump or in a barrel; VS1 through VS7 cover specific column, bowl, and bearing configurations. SP (submersible) pumps mount the motor below the process liquid. The type selection drives casing pressure rating, materials availability, and the achievable head per stage.
What does an API 610 datasheet carry?.
The API 610 datasheet is structured into operating conditions (capacity at rated, normal, minimum continuous stable flow, and BEP), site and utility conditions, pump construction (casing, impeller, shaft, wear-rings materials), bearing arrangement, seal arrangement (referencing an API 682 seal plan), driver coupling and baseplate, lubrication, instrumentation, inspection and testing requirements, and a list of vendor data deliverables. The form is structured so two vendors bidding the same service can be compared field by field. Vendor-supplied performance curves at the rated and BEP points back the bid; site conditions (elevation, atmospheric pressure, ambient temperature) drive the NPSHa calculation that pairs with the vendor's NPSHr.
What changed in the 12th edition?.
The 12th edition (2021) increased the minimum efficiency expectations through alignment with the ASME PTC 8.2 efficiency test code, expanded the seal-plan selection guidance to align with API 682 4th edition, made variable-speed-driven pumps a first-class case (rather than an exception), and tightened the acceptable vibration range under ISO 10816-7. Condition-monitoring instrumentation (bearing-temperature RTDs, seal-leakage detection, vibration probes on certain pump types) moved from optional to standard. The datasheet form expanded by approximately 15% to accommodate the new fields.
Frequently asked.
Is API 610 the same as ISO 13709?
Yes. ISO 13709 is the identical international standard. The two documents share the same technical content; ISO 13709 is the formal ISO publication, API 610 is the American Petroleum Institute publication. Specifications written to API 610 are interchangeable with specifications written to ISO 13709.
What is the difference between API 610 and API 685?
API 685 governs sealless pumps (magnetically driven and canned-motor pumps) for the same industries API 610 covers. The two standards parallel each other in scope but apply to different pump construction. API 685 is used where seal leakage cannot be tolerated (light hydrocarbons, acutely toxic service, certain chemical processes).
Does API 610 apply to water-service pumps?
API 610 is specified by service and by purchaser preference rather than by fluid. Cooling-water pumps in a refinery may be specified to API 610 if the operator's specification calls for it; the same pump in a municipal water utility would typically be specified to ANSI/HI standards or to a vendor's commercial standard. The choice is driven by the operating philosophy and the criticality of the service.
What is the typical lead time on an API 610 pump?
Lead times depend on pump type, materials, and vendor production schedule. Standard carbon-steel OH-type pumps from major vendors typically run 16 to 28 weeks from purchase order to ready-for-shipment. Specialty materials (high-nickel alloys, duplex stainless), BB-type multi-stage pumps, and vertical pumps with long columns can extend to 40 weeks or more. Bid-stage planning typically anticipates 24 to 36 weeks for budget-grade procurement schedules.