KSB Omega Axially Split Volute Casing Pump

Overview

The KSB Omega is a single-stage axially split volute casing pump with a double-entry radial impeller, built for horizontal installation and, as the Omega V, for vertical installation. It moves large volumes of water at moderate head: KSB gives flow rates up to 4,400 m³/h, heads up to 210 m, operating pressures up to 25 bar and fluid temperatures from 0 to 140 °C, depending on material and size, with discharge nozzles from DN 80 to DN 400. Its main applications listed by KSB are waterworks, desalination plants, pressure boosting, water transport, service and cooling water for power stations and industry, irrigation and drainage pumping stations, fire-fighting systems, shipbuilding, and district heating and district cooling.

Seven Star LLC supplies the KSB Omega to water utilities, desalination and power plant operators, district cooling providers and EPC contractors in the Sultanate of Oman and the GCC. Our Muscat engineers help translate your duty point, NPSH available, fluid and drinking-water requirements into the KSB designation code covering size, impeller type, material variant, shaft seal, bearing lubrication and generation.

Operating Principle of the KSB Omega

In the KSB Omega water enters a suction branch in the lower casing half and is split into two streams that reach the double-entry impeller from both sides. Because the impeller draws equally from each side, the axial thrust is balanced hydraulically, which reduces the load on the rolling element bearings. The impeller discharges into a double-volute casing that balances the radial forces on the shaft, so vibration stays low across the operating range. A short, rigid shaft that stays completely dry, with shaft protecting sleeves in the seal area, carries the impeller between two bearing housings.

The double-entry layout also gives a low required NPSH for a given flow, which makes the pump suitable for suction from reservoirs, wet wells and seawater intakes. KSB notes that the hydraulic system is optimised for high speeds and that the double-volute casing and rigid shaft enable a compact, energy-efficient design, so a single pump can replace several smaller end-suction units in a large station. For even larger flows KSB directs users to the RDLO type series.

Engineering Design of the KSB Omega

The casing is split axially along the shaft centreline, with integrally cast pump feet on the lower half and replaceable casing wear rings; optional impeller wear rings are available. Removing the upper casing half by its hexagon head bolts gives direct access to the rotor without disturbing the suction and discharge pipework or the motor alignment, and self-centring components such as the rotor, mechanical seal, upper casing half, bearing housings and seal housing make reassembly fast. Mating dimensions follow EN or ASME. Horizontal pumps use grease-packed rolling element bearings sealed for life; the Omega V Generation 2 uses life-greased rolling bearings top and bottom.

KSB Omega material variants include nodular cast iron casing with bronze impeller (SB), nodular cast iron with stainless steel impeller (SC), grey cast iron options, and full duplex stainless steel (DD35) for seawater and brackish water. Shaft seals are single or double mechanical seals, balanced (carbon/silicon carbide) or unbalanced (silicon carbide/silicon carbide), with gland packing available on Generation 1. Drinking-water designs to ACS, WRAS, NSF/ANSI 61 and 372 and UBA are offered, and coatings range from epoxy for indoor use to polyurethane for outdoor and marine atmospheres, with a drinking-water approved epoxy interior coating.

Key Features of the KSB Omega

The KSB type series booklet lists these benefits for the KSB Omega.

• Double-entry impeller that balances axial thrust and reduces bearing loads.
• Double-volute casing that balances radial forces for low vibration in operation.
• Short, rigid, completely dry shaft with spring-loaded bearing arrangement for long bearing, seal and coupling life.
• Axially split casing with a solid split flange for reliable sealing and direct access to the rotating assembly.
• Self-centring rotor, seal, casing half and bearing housings for fast, accurate maintenance.
• Corrosion and abrasion-resistant wear rings, sleeves and impellers, including a duplex stainless steel DD35 variant.
• Horizontal Omega and vertical Omega V versions with DN 80 to DN 400 discharge nozzles.
• Drinking-water designs and coatings to ACS, WRAS, NSF 61/372 and UBA requirements.

Industrial Applications

Large water movements are central to Oman’s infrastructure, and the KSB Omega is built for exactly these duties. Water transmission pumping stations that carry desalinated water from coastal plants at Barka, Sohar, Sur and Salalah to inland reservoirs need high flow at a steady head, while desalination plants use the pump for seawater intake, product-water transfer and brine discharge, where the duplex DD35 material resists chlorides. Irrigation and drainage pumping stations, stormwater networks and treated-effluent reuse schemes are further typical uses.

District cooling plants serving Muscat developments use axially split pumps for condenser water and chilled water circulation because of their efficiency and easy maintenance, and power and petrochemical plants in Sohar and Duqm rely on the KSB Omega for cooling-water and service-water circuits and fire-fighting water mains. Seven Star LLC supplies the pump and its wear parts and seals with engineering support in Muscat, alongside smaller units such as the KSB Etanorm end-suction pump for auxiliary duties.

Technical Specifications

The KSB Omega data below are from KSB type series booklet 1384.5/17-EN (Omega / Omega V, Generation 1 and 2). Limits depend on size, material variant and design.

How to Order

To request a quotation for the KSB Omega, send Seven Star LLC your flow, head, NPSH available, fluid and temperature, preferred material variant, seal type, horizontal or vertical installation and any drinking-water approval required. Our team in Muscat will confirm the designation code and motor, advise on stock and delivery for Oman and the GCC, and the KSB type series booklet can be downloaded from this page. For high-pressure duties see the Grundfos CR vertical multistage pump and for borehole supply the Grundfos SP submersible pump.