Armstrong, HSC Pump, Horizontal Split Case Pump, Series 4600The Series 4600 is the state of the art Horizontal Split Case Pump – based on the "Tilted Parting" concept to minimize turbulence at the eye of the impeller by its straight laminar approach, thus maximizing efficiency. This also results in the lowest profile and minimum floor space of any HSC pump, lowering installation costs. Cartridge seals and bearing removal nuts ensure ease of maintenance.

Armstrong, HSC Pump, Horizontal Split Case Pump, Series 4600

Design Features

Cartridge style mechanical seal. Mechanical seal and seal plate are mounted on the shaft sleeve, as a single, cartridge style, assembly.

Service with ease. The one piece cartridge assembly is easily removed for service. The replacement assembly may be installed, just as easily, with no special seal adjustments necessary. Standard mechanical seal is an industry standard design, that is readily available at local seal supply houses.

Greater temperature and pressure parameters Various types of mechanical seals and packed glands, are available to extend the standard pressure and temperature parameters.

SERVICE OF BEARINGS: Bearings may be removed without disturbing top cover. Remove the bearing cover to expose the bearing for service.

Service with ease All bearings contain a removal nut on the impeller side of the bearing. Bearing removal is easy. Simply lock the shaft and rotate the removal nut, until the bearing is free.

No special tools or adjustments are necessary.

Typical Specifications

Pumps – Horizontal Split Case, Centrifugal

Provide Armstrong Horizontal Split Case pumps, single stage, double suction type, with pump characteristics which provide rising heads to shut off.

Refer to pump schedules for pump flows, heads, motor speed, enclosure, efficiency and power requirements.

Pumps shall be Armstrong Series 4600 Horizontal Split Case type, each with flexible type coupling and fully enclosed ANSI B15.1 Sect 8 and OSHA 1910.219 compliant guard and mounted, with motor, on a fabricated steel baseplate.

Pump Construction

Pump Casing – Cast iron, axially split, with suction and discharge connections located in the lower casing. The connections shall be flanged and of sizes indicated in the schedule and shall be drilled and tapped for gauge connections. Suction and discharge connections shall be on the same elevation. The top of the casing and the rotating assembly shall be removable for service without disturbing the piping connections.

Wearing Rings – The pump casing shall be fitted with replaceable bronze wearing rings.

Impeller – Bronze, double suction, fully enclosed type. 2-plane dynamically balanced.

Shaft & Shaft Sleeves – The pump shaft shall be carbon steel, designed for minimum deflection and vibration and be fitted with bronze shaft sleeves.

Mechanical Seals – Each seal chamber shall be fitted with a cartridge type mechanical seal. The seal component shall be of stainless steel construction with carbon vs silicon carbide faces and EPDM secondary seal. Each mechanical seal, shaft sleeve and seal plate shall be easily removable as a single component. Provide factory installed stainless steel braided flush lines.*

Bearings – Supply dust tight deep groove ball bearings, with permanently sealed grease type lubrication.

Bearings shall be mounted in cartridge type housings and shall be replaceable without opening the pump casing.

Bearings shall be removable by simply rotating the removal nut. No special tools or pullers are to be necessary.


Motor Horsepower ratings shown on the schedule are minimum acceptable and have been sized for continuous operation without exceeding full load nameplate rating over the entire pump curve, exclusive of motor service factor.

Mounting and Testing

Pumps shall be hydrostatically tested to 150% of the maximum pump working pressure.

The pump and motor shall be mounted and aligned at the pump manufacturer’s facility on a common baseplate designed to ANSI/HI 1.3.5 rigidity standards for freestanding bases. Final alignment shall be made, on site, after the pump is installed and brought to operating temperature. (If supplied) The drip pan tapped connection shall be piped to the nearest drain.

* Provide the following seal flush line environmental accessories:

1.Supply in each flush line to the cartridge mechanical seal a 50 micron cartridge sediment filter and sight flow indicator, to suit the working pressure encountered. Filters shall be changed, by the installing contractor, after system flushing and on a regular basis until turned over to the owner.

2.(For pumps with differential pressures exceeding 30 psig (2 bars) only): Supply in each flush line to the cartridge mechanical seal a cyclone type sediment separator, with sight flow indicator.

Series 4600 Product Information
Series 4600 I&O Instructions