S 125-500 Horizontal Split Case Pump

S 125-500(I) Reference Configuration

The duty point and added power/suction data refer to S 125-500(I) in the S-Series catalogue (11 March 2026), original page 23. See APP-S-CONFIG Rev. A for the selected configurations. Family ranges combine variants and impeller diameters from APP-S-DAT Rev. A; range endpoints are not paired duty points. Select the curve and motor for the actual operating range.

Shaft power is the power absorbed by the pump at this point. Catalogue motor rating is the listed driver size. Compare system available NPSH with the selected NPSHr and required engineering margin.

Compact discharge, higher-head reference

The 328 m³/h at 76 m reference is useful for an initial higher-head comparison in the DN 125 group. Confirm the actual duty, suction conditions and impeller rather than selecting from discharge size alone.

The nominal designation describes a size family. Provide actual flow, head, speed, liquid and temperature so engineering can check the proposed operating point against the individual curve, impeller trim, power and NPSHr.

Current duty and suction conditions

Include minimum and normal operating points, source level or suction pressure, liquid temperature, suction-pipe losses and the intended speed-control arrangement. These inputs help establish whether this model is suitable for the system.

Performance Curve, GA and Replacement Fit

Request the size-specific Q/H, efficiency, power and NPSHr curves for the proposed trim and actual speed. A family coverage field and this reference table are screening aids; the selected curve establishes the duty review.

For an installed-pump replacement, send the full existing designation, nameplate and available GA. Compare suction and discharge flanges, drilling and facing, nozzle centerlines, shaft height and extension, rotation, coupling and anchor-bolt pattern. Matching numerical size codes alone do not establish interchangeability with KSB Omega or another brand.

Materials, Seals and Supply Scope

Catalogue casing options include HT250 grey cast iron, QT400-18 ductile iron and ZG230-450 cast steel. Impeller and wear-component options include the listed bronze, iron, silicon-brass and stainless grades. Choose the construction against the actual liquid, temperature and project specification.

Specify a bare pump when the existing driver is intended for reuse, or a pump, motor and baseplate set for a coordinated supply. Include the required material standard, EN 10204 3.1 records, dimensional checks and witness or third-party inspection requirements in the inquiry.

Questions About This Model

Request S 125-500 Engineering Review

Open the inquiry with S 125-500 already selected, describe the required duty and attach any available curve, nameplate or drawing. The engineering team responds within 24–48 hours with the review status and next required inputs.