Within the marine industry the pumps are suitable as:
- Fresh and seawater cooling pumps
- Bilge and ballast pumps
- General service pumps
- Transport of slightly aggressive liquids with low viscosity such as diesel and lubricating oils.
Within industrial and utility applications the pumps are suitable for:
- Industry water circulation
- Cooling tower distribution
- Diesel transfer
- District heating
- District cooling
The DESMI NSL pump meets the special marine and industrial market requirements for:
- High efficiency
- Low NPSH values
- Easy installation/service
- Specific materials
- Compact design
- Standardized to modular design
- Outstanding hydraulic design performance
- Spacer-coupling options for easy maintenance
- Robust shaft design
- High efficiency impeller with low NPSH values
- Self-priming ability with a separate built-on priming pump
|Nominal diameter (DN)||65 to 400|
|Flow rate||Up to 1800 m³/h (7900 US gpm)|
|Head||Up to 220 m (720 ft)|
|Pressure||Up to 25 bar (363 psi)|
|Temperature||Up to 150°C (302°F)|
|Motor||Standard and EX motors|
|VFD||Direct or Bulkhead/Wall-mounted|
Technical Product Specifications
The design of the NSL pumps is for medium/high flow capacities up to 1800 m³/h (to 7,900 US GPM) & medium head up to 220mLC. The pump can be configured as vertical and be of the radially split, single stage centrifugal pump type with connecting flanges according to international standards or as horizontal in-line and radially split, single stage centrifugal pump with connecting flanges according to international standards acc. to DIN, ANSI or JIS.
Material construction of the pump casings needs to be ductile cast iron GGG40 EN1561-GJL-400/DIN1693 for plain water, which shall be able to manage a working pressure of 16 bar (tested 1,5 x working pressure). For seawater applications, the pump construction of the casing shall be RG5 bronze EN1982 CC491K/DIN17656.
The pump casing shall be equipped with a NiAlBz EN1982 CC333G/DIN17656 replaceable sealing ring. Material of the shaft shall always be of high quality duplex stainless steel AISI329/1.4460. The pumps to be fitted with bearings at both top and bottom to give a robust construction, designed for trouble free continuous duty.
The pump needs to be fitted with dynamically balanced impellers acc. to ISO1940/1-1986 (E) G6.3 that incorporates advanced double-curved blades to ensure low NPSH-values and high efficiency resulting in lower energy consumption and therefore lower running costs.
The construction material of the impeller shall be NiAlBz EN1982 CC333G/DIN17656 (as standard) or duplex stainless steel AISI329/1.4460. The seal type shall be a single acting, mechanical shaft seal, which seals off the liquid cavity at the motor shaft.
The pump can be equipped with a spacer coupling, which is a combined distance and flexible coupling between drive unit and electric motor. This makes it possible to remove the complete bearing housing with shaft, bearings, shaft seal and impeller – without dismantling the motor or pump from the piping. This represent significant advantages to the end user, who with this pump solution secures his installation trouble free maintenance with minimum down time.
NSL Centrifugal Pump
NSL Centrifugal Pump (Monobloc) – overhaul video
DESMI Overhaul video NSL Centrifugal Pump NSL 200 265 14