Flowserve Worthington LPN API 610 BB1 Axially Split Pump

Flowserve LPN API 610 BB1 axially split double-suction pump

The Flowserve LPN (Worthington LPN) is a single-stage, axially split, double-suction pump designed to ISO 13709/API 610 as a BB1 between-bearings machine. Flowserve positions it as the medium-pressure choice with side-and-side nozzles, favoured for hydrocarbon and water transfer. The near-centerline mounting suits refinery services governed by API selection criteria for flammable or hazardous fluids with a specific gravity above 0.70 and temperatures below 200 °C. Seven Star LLC supplies the LPN in Oman and the GCC as an independent supplier in Muscat.

A double-suction impeller draws liquid into both sides of the eye, which balances axial thrust hydraulically and gives a low NPSH requirement that a single-suction overhung pump cannot match. That makes the LPN a natural fit for transfer pumps taking suction from tanks or low-level vessels, and for large-flow water services.

What the LPN, LPN-V and LPN-H variants mean

LPN technical specifications

How the LPN is built for reliability

The double volute minimises radial hydraulic loads even at minimum flow, which reduces shaft deflection and extends bearing, seal and wear-ring life. The stiff shaft operates below its first critical speed. Nozzles are integrally cast in the lower casing half, so the rotor, seals and bearings can be serviced by lifting the top half without disturbing the piping. A confined gasket design gives metal-to-metal contact for correct gasket compression, which also prevents corrosion of bolts and nuts. The bearing housing is carbon steel with 180-degree bolting to heavy-duty brackets and standard labyrinth seals; bearing isolators are optional.

Bearing and lubrication choices on the LPN

Three bearing arrangements are offered. The standard design uses ball bearings with an oil slinger system, which draws oil into the bearings without foaming. It is applied while the energy density (power times rated speed) stays at or below 4.0 million kW·rpm (5.4 million hp·rpm) and the thrust bearing life and speed are within ISO 13709/API 610 limits. Above those limits the sleeve radial bearing with tilting-pad thrust bearing and forced-feed lubrication is used; the oil can come from a shaft-driven pump or from separate lube-oil pumps. A ring-oil sleeve/ball variant sits between the two. Cooling is by fan, water or the pumped product, so bearing temperature can be held on hot services.

Where the LPN fits among Flowserve API pumps

The brochure lists the DVS and DVSH BB1 pumps, the UZDL two-stage BB1, the HDX and HED-DS BB2 radially split pumps, the PVXM vertical in-line pump and the HPX OH2 pump as complementary designs. The DVSH, UZDL, PVXM and HPX are covered on other pages of this site. Pick the LPN when you need a flow up to 15,000 m³/h at moderate head, and the DVSH when higher pressure or head are needed.

Selection and ordering checklist for the LPN

• Rated, minimum and maximum flow and the differential head.
• NPSH available; the double suction allows low NPSHR.
• Liquid, specific gravity, temperature and solids; reject services above 204 °C or SG below 0.70 against the stated scope.
• Casing rating: LPN to 25 bar or LPN-H to 50 bar, and flange Class 150 or 300.
• Horizontal, or LPN-V vertical, based on available space.
• Seal arrangement and bearing design including cooling.
• Rotation direction, driver, baseplate type and test requirements.

Installation, commissioning and maintenance

Baseplate options include welded steel for grouting, skid type non-grouted, three-point support and pre-grouted designs. Check coupling alignment hot and cold on high-temperature services. Because the top casing half lifts off, sufficient crane access over the pump is needed. Typical maintenance includes seal and bearing service and wear-ring replacement at planned outages. Pump packages with lube oil piping, seal system, monitoring instruments and driver mounting are available to specification.

Typical applications of the LPN in Oman and the GCC

Flowserve lists hydrocarbon and water transfer, petroleum refining, petrochemicals, pipeline duty, power generation, gas scrubbing, firefighting and cooling water as applications. In Oman and the GCC it is a candidate for crude and product transfer at terminals, cooling-water circulation in power and desalination plants, and fire-water pump systems where large flow and low NPSH matter.

Information to send with your LPN RFQ

• Liquid, temperature, specific gravity and vapour pressure.
• Flow range and differential head or pressure.
• Suction conditions and NPSH available.
• Casing pressure class and materials.
• Driver, speed and frequency; seal and bearing plans.
• Delivery site and inspection requirements.

Documents and quotation

The Flowserve LPN brochure PS-20-5 is attached on this page. Send your duty data and the LPN variant you need, and we will confirm availability and lead time. Seven Star LLC is an independent supplier and does not claim any official status with the manufacturer.