Flowserve SVCN 7 Installation Operation & Maintenance Download

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SVCN 7 INSTALLATION, OPERATION, & MAINTENANCE

NOTE

An operating procedure, condition, etc., which is essential to
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1.3 CONSTRUCTION

The SVCN 7 pump has these basic design features: it is centrifugal and single suction; it has a
cantilever rotor and a centerline-supported, radially split case which is either single- or double-
voluted. Its major components are case, head, rotor, ball bearings, bearing housing, and mechanical
seal or packing. The case houses the impeller, the head contains the packing gland with packing or
the seal parts, and the bearing housing supports both radial and thrust ball bearings. (The radial
bearing is on the impeller end of the rotor; the thrust bearing is on the coupling end). There are
renewable wearing rings on the impeller hub and skirt, in the head, and in the case; all are held in
place by either tack welds or set screws that are staked in place. Holes are drilled in the impeller for
balancing the hydraulic thrust load. Commonly a hook-type shaft sleeve prevents the packing or
mechanical seal from wearing into the shaft. Cartridge seals are also used.

The following paragraphs contain a brief description of each optional feature with an engineering
drawing reference that identifies its relevance to your pump. Some of the features are alterations of
basic components such as the case, the head, and the bearing housing.

1.3.1 PUMP CASE

Options in case design provide double-voluted construction for the case with a 4-in (100 mm)
discharge nozzle and larger and single-voluted construction for the case with a 3-in (75 mm) or
smaller, discharge nozzle. Vent, drain, and gauge connections are optional. Those incorporated in the
case are shown by the pump and motor driver OUTLINE drawing. Drains are drilled through the
inner volute of the double-volute pump. With any case design, all major parts of the pump can be
removed as a unit (once the coupling spacer is removed) without disturbing the position of the case,
the discharge and suction piping, or the driver.

1.3.2 BEARING HOUSING

An air cooled bearing housing that incorporates a fan on the radial end of the bearing housing is
standard on the SVCN 7 pump to expose more surface area to ambient air. This design improves heat
dissipation generated by the bearings. In some sizes, an additional fan to provide forced air
circulation is located at the bearing housing thrust end. SVCN 7 pumps with two fans are designated
as "fan cooled". SVCN 7 pumps are available with water cooled bearing housings. The water cooled
housing incorporates a sump cooling tube located in the bottom of the bearing housing. Water
continuously flows through this tube and removes bearing generated heat which is dissipated in a heat
exchanger or by some other means provided at the plant.

The bearing housing is drilled and tapped to provide for either pure mist or purge mist lubrication
connections. Threaded holes are provided in the bearing housing for viewing oiling rings and are
normally plugged with pipe plugs. These same holes may be used to connect a pure mist lubricating
system.

1.3.3 BEARINGS

The standard radial bearing is a single row, deep-groove (Conrad type) ball bearing. The standard
thrust bearing is a duplex, single-row, 40-degree angular contact type (7000 series), installed back to

DO2604-13

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