Alfa Laval LKHPF High-Pressure Hygienic Centrifugal Pump

Alfa Laval LKHPF high-pressure hygienic centrifugal pump

The Alfa Laval LKHPF is the LKH hygienic centrifugal pump reinforced for high inlet pressure. It is designed for inlet pressures up to 40 bar (600 psi) and for cleaning in place, which makes it a booster and feed pump for membrane filtration lines. Seven Star LLC supplies the LKHPF in Oman and the GCC as an independent supplier in Muscat.

In the part name, LKH is the premium hygienic pump family and the added letters mark the high-pressure filtration version. The pump page describes it as particularly suited to nanofiltration and reverse osmosis installations, and it is also the family member to consider wherever the suction side is already pressurised.

LKHPF technical specifications

How the LKHPF copes with high inlet pressure

The pressure capability comes from the structure rather than from the hydraulics. A heavier casing and backplate, special internal seals and a bolted arrangement with multiple heavy-duty studs hold the pump together when the suction side is already at filtration pressure. The wet end otherwise follows the LKH design: a semi-open impeller whose vane shape gives low NPSH required and reduces cavitation risk.

Balance holes in the impeller improve circulation around the shaft seal and reduce axial forces. The seal is mounted outside the product zone, with spring and washers on the atmospheric side, and the balanced design limits the chance of the seal opening during a pressure shock, which is a real consideration on membrane plants where valves close quickly.

Where the LKHPF fits in a filtration system

The pump is normally used as the circulation or feed pump around a membrane skid. It sits next to the standard LKH pump, which handles ordinary hygienic duty at lower inlet pressure. If the pressure at the suction flange never approaches the high range, the standard LKH is simpler. For air-laden CIP return use LKH Prime, and for ATEX areas the LKHex.

The wide performance envelope can remove the need for parallel or serial pump arrangements, which saves piping and instrumentation on a skid. Whether a single pump is enough still depends on the duty point and should be checked against the curve.

Selecting and ordering the LKHPF

• Suction pressure at the pump flange, including the highest value during start-up and cleaning.
• Required flow and differential pressure at 50 Hz or 60 Hz.
• Fluid, temperature and cleaning programme, as filtration plants often clean with hot chemicals.
• Seal type: single, flushed or double.
• Elastomer grade matched to product and cleaning chemicals.
• Motor and mounting arrangement.
• Number of units, if parallel operation is under consideration.

Installation, commissioning and maintenance of the LKHPF

Check that every upstream and downstream component matches the pressure level: a pump rated for 40 bar inlet is of no use in a skid whose flanges or clamps are not. Tighten studs evenly according to the manual. Vent the pump before starting and verify that flush connections are supplied when a flushed seal is used.

Seal change is quick because the seal is front-loading, and the same LKH single shaft seal fits many LKH models. Alfa Laval provides service videos on its pump page for changing flushed, single and double seals. Record the serial number and keep the standard spare seal kit and gaskets in stock.

Practical points for high-pressure service on the LKHPF

A pump on a membrane circuit is rarely alone: a pressure relief device, a non-return valve and a flow control element often sit around it. Think about what happens at start-up, when the circuit is not yet pressurised, and at shutdown, when pressure may trap between closed valves. Both situations change the load on the seal and the studs. Make sure the sequence in the control system follows the manufacturer’s instructions and never runs the pump against a closed discharge for long.

For a replacement project, note the existing pump size and impeller from the nameplate and compare it with the new duty. A plant that has changed its membranes may now need different pressure than the original selection.

Typical applications in Oman and the GCC

Membrane filtration is common in dairy, juice and beverage processing, and in biotechnology and pharmaceutical purification. In Oman and the GCC the same pump class is relevant wherever concentration or clarification is done with nanofiltration or reverse osmosis on hygienic products. Ambient heat in the utility area increases cooling demand for motors, so allow sufficient ventilation around the drive.

LKHPF against the other LKH variants

Information to send with an RFQ for the LKHPF

• Part name LKHPF and, if known, the pump size.
• Maximum suction pressure and discharge pressure.
• Flow, frequency and fluid data.
• Seal, elastomer and motor options.
• Nameplate data of an existing pump.
• Delivery location and date.

Documents and quotation

Send us the part name and your pressure data, and we will confirm which manufacturer documents are available for your duty.

Seven Star LLC will then prepare a quotation for supply in Oman and the GCC.