Identification
Horizontal single-stage overhung process pump to API 610 / ISO 13709 type OH2 by Flowserve: casing supported at the centerline (the construction difference that defines the OH2 — the casing expands symmetrically in hot service, preserving alignment) and a seal chamber per API 682. It is the severity step above the B73.1/ISO 5199 chemical platforms: hydrocarbons, high temperature, high pressure, a 20+ year design-life requirement.
Position on the six axes
| Axis | Position |
|---|---|
| Hydraulics | Radial (single-stage) |
| Stages | 1 |
| Configuration | OH2 (centerline-mounted) |
| Sealing | Sealed — API 682 chamber, full piping plans |
| Standard | API 610 / ISO 13709 |
| Service | Refining, petrochemical, O&G |
Ranges and construction
| Parameter | Catalog value |
|---|---|
| Flow | up to ~2,000 m³/h |
| Head | up to ~350 m |
| Pressure | up to ~80 bar |
| Temperature | −160 °C to +450 °C |
Centerline support for nozzle loads beyond API 610 requirements; a suction-nozzle guide vane (uniform inflow — NPSH margin); materials across the API classes (S-6 to A-8, incl. duplex). The cryogenic end (−160 °C) covers LPG/light LNG service.
Line variants
| Variant | What it solves |
|---|---|
| HPX | The standard refining OH2 (ranges in the table above) |
| HPXM | Low flow / high head (up to ~30 m³/h and ~215 m) with dedicated hydraulics and a stable rising curve down to minimum flow — the duty that would ruin a standard OH2 far from BEP |
| HPX-V | The same platform as a vertical in-line (API 610 OH3) — minimal footprint |
| HPX6000 | Solids-handling (slurry) execution of the same family |
Materials across the API 610 classes (carbon steel, chrome, austenitics, duplex), per service datasheet.
Differentials and points of attention
- Optional inducer: for installations with tight NPSHa, the high-suction-specific-speed axial inducer cuts the set's NPSHR — the catalog solution to the problem treated in the cavitation note.
- Suction-nozzle guide vane: uniform inflow at the impeller eye — NPSH margin and part-load stability.
- Centerline support sized for nozzle loads ABOVE API 610 requirements — preserves alignment with hot piping.
- Point of attention: like every API platform, the value shows in severe service — in cold, mild service the HPX is the classic overspec the API itself discourages (paying for B73.1/ISO 5199 solves it).
Where it stands out / limitations
Stands out exactly where B73.1 stops: hot service (the OH1's foot mounting misaligns with thermal growth — the centerline does not), hydrocarbons with critical sealing (native API 682), O&G design audits (full API datasheets). Limitations: an acquisition cost several times an equivalent chemical pump — specifying API 610 for cold, mild service is the classic overspec the API itself discourages; for head beyond the range, the path is a multistage BB (e.g., Sulzer MSD).
Official documentation
- HPX product page — Flowserve — specifications and literature.
- Official technical brochure (PUBR000427) and IOM in the Flowserve literature library (D05 — always the official source).
Reliability
No catalog MTBF, like the whole category — but it is for this class that the best field benchmarks hold: well-run refineries operate API pumps at 3 to 10 years MTBF (Bloch), and API 610 exists precisely to buy that longevity by design (margins, nozzle loads, 682 sealing). Failure hierarchy and critical reading in "Reliability in numbers" in the Centrifugal Pump handbook.