Products > Surface centrifugal pumps > Self priming pumps with open impeller, for dirty liquids

VARISCO has become a household name around the world for reliable pumps for difficult applications. Born as a family company, it is now part of an international group fully committed to growth in niche markets. Continual investments in latest generation machine tools make the factory at Padova one of the best in its field. Main advantages of VARISCO self priming pumps are :
- Rapid self-priming: without standing valve. Once filled with water, the pump is automatically primed to a height of 7.5 m.
- Simple construction: only one moving part: the impeller. Open-blade impeller allowing the passage of wide solid bodies and easy inspection
- High resistance to abrasive liquids: the wear plate is easily replaceable.
- Axial mechanical seal lubricated from the outside: no leaks or infiltration of air along the shaft.
- Easy to install: only the suction pipe needs to be immersed in the liquid. The pump can be located above and in a dry place, in the most suitable location for service and control.
- Long life: the parts subject to wear can be easily replaced, a number of times when necessary, restoring the original performance of the pump.

SELF PRIMING PRINCIPLE
The air is drawn into the pump due to the negative pressure reated by the moving impeller and is emulsified with the liquid contained in the pump body. The air-liquid emulsion is forced into the priming chamber where the lighter air is separated and leaves through the discharge pipe; the heavier liquid drops back down into circulation. Once all of the air has been expelled from the suction pipe, the pump is primed and works like a normal centrifugal pump. The pump can also work with an air-liquid mixture. The non-return valve has a dual function: it prevents the suction pipe from emptying when the pump is off; in the event of accidental emptying of the suction pipe, this holds a sufficient amount of liquid in the pump body to prime the pump. The discharge pipe must be free to expel the air coming from the suction pipe.
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VARISCO E series

Economic series without self-lubricating mechanical seal. Mainly available in close-coupled version with electric motors but also available in bare shaft version or close coupled to petrol/diesel engines.
SPECIFICATIONS
• For dirty liquids with solids in suspenstion 8-38mm
• Max flow 100 m3/h, max head 27m
• Max water temperature 60°C
MATERIALS
• Pump body and impeller in cast iron
• Stainless steel shaft
• Mechanical seal carbon/ceranic/nbr
• On request, mechanical in seal tungsten carbide
MOTOR DATA
• 2 pole motor (2900rpm)
• Isolation class F, protecton IP54
• Voltage 3~ 230V/400V 50HZ
• E50 size is also available in 1~ 220/240V 50Hz

VARISCO J series

Nine sizes availabe from 1 1/2" to 12". Very wide range of applications and many options for the materials of construction.

Heavy duty casing in cast iron, bronze or stainless steel. Easily opened priming, drain and impeller inspection covers. Ductile iron, aluminium bronze or stainless steel open impeller handling large diameter spherical solids. Easily replaced cast iron, oil and abrasion resistant rubber faced cast iron, bronze or stainless steel wear plate(s). Externally lubricated mechanical seal. Can run dry on high vacuum even when pumping highly abrasive liquids. Silicon or tungsten carbide seats (graphite rotating seat for versions for petroleum products). Bearing housing with heavy duty bearings suitable for direct or V-belt drive. Standard diameter shaft extension bored and tapped to facilitate the assembly of couplings or pulleys.
SPECIFICATIONS
• For dirty liquids with solids in suspenstion 11-76mm
• Max flow 1200 m3/h, max head 65m
• Max water temperature 60°C
• Most types also available in ATEX version

VARISCO J TRM series

Same features as J series, but with mag drive. For liquids like acetones, polyol, ammonia, coustic soda, nitric acid etc.

Why mag drive?
The growing demand for pumping systems that make it absolutely impossible for pumped liquids and relevant vapours to pollute the surrounding atmosphere and vice versa - resulting in chemical-physical reactions liable to alter the fluid used in the process irreparably - persuaded Varisco to come up with these new magnetic drives to be applied on the already widely popular, tried and tested internal gear rotary pumps.

VARISCO ST series

Super heavy duty series for big solids handling. Big ports for easy inspection and cleaning of the internal parts. Sizes 2" to 8" available.
SPECIFICATIONS
• For dirty liquids with solids in suspenstion 38-76mm
• Max flow 400 m3/h, max head 30m
MATERIALS
• Pump body and impeller in cast iron
• Stainless steel shaft
• Sel lubricating mechanical seal in silicon carbide

MA series

Economic self priming series with open impeller.

SPECIFICATIONS
• For dirty liquids with solids in suspenstion
• Max flow 70 m3/h, max head 45m
MATERIALS
• Pump body in cast iron
• Bronze impeller
• Stainless steel or hardened steel shaft
• Soft packing or mechanical seal

All bare shaft pumps are also availabe as complete units with electric motors.