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Product code: NR-RPP Rotary Piston Pumps

North Ridge NR-RPP Rotary Piston Pumps

Pump Type - Rotary Piston

Max Flow Rate - 64M³H

Max Head - 50M

Pump Materials - AISI316, Bronze, Cast Iron

Max Temp - 300°C

Max Viscosity - 200,000 cst

Max Solid Passage - 0mm

Self Priming - Y

Inlet/Outlet Sizes - 9mm to 100mm

Drive - AC Electric, Bareshaft

Max Suction Lift - 8M



North Ridge NR-RPP Rotary Piston Pumps

Flow Rate

Up to 64 m³/hr

Head (Pressure)

Up to 5 bar

Sizes Available

From 3/8” to 4”

Operating Temperature

Up to 300°C


Up to 200,000 cSt

Drive Options

Electric Motor, Hydraulic Motor, V-Belt

Construction Materials

Cast Iron, Stainless Steel and Bronze


The North Ridge NR-RPP Rotary piston pumps are positive displacement volumetric self-priming pumps, with fantastic self-priming capabilities, they can also be used in reversed meaning the suction can become the discharge side if required a feature extremely helpful for loading, offloading and mixing applications, these pumps are capable of handling a quite large variety of  fluids from low (10 cSt) to high viscosities (200,000 cSt) and a max. temperature of 300 °C. These pumps can maintain a high volumetric efficiency even when pumping extremely viscous fluids this along with their high suction capabilities make our rotary piston pump range the most suitable selection for most process, transfer, decanting and mixing applications.



Design Features/Benefits:


        ATEX Certified

        High Efficiency Even with Highly Viscous Fluids

        Temperatures Up to 300 °C

        High Self-priming Capabilities

        Capable of Handling Viscosities Up to 200,000 cSt

        Reversible – Clockwise and Anticlockwise

        Capacity achieved is directly proportional to their working speed



Typical Applications/Fluids:

        Food - edible oils, chocolate, tomato paste, jams, honey, butter, mayonnaise, molasses, cake batter, dry food etc.


        Cosmetics and more - detergents, soaps, toothpaste, beauty creams, perfumes, acetone etc.


        Fuels and oils - thermal oils, mineral oils, kerosene, diesel, fuel-oil, gasoline, white spirits, toluene, gasoil etc.


        Industrial fluids - adhesives, emulsions, grease, resins, paraffin, asphalt, bitumen etc.


No, definitely not! Rotary piston pumps will incur damage even after short periods of dry running. Firstly, the piston requires lubrication from the pumped fluid, for example fuel and oil. Dry running without these will cause fast and irreversible damage. The mechanical seal requires lubrication and cooling while the pump is operating. Without the presence of fluid, the mechanical seal will overheat and crack, and this may cause the pump to leak and fluid to enter the motor. There is also the possibility that the motor will burn out. Our advice is to ensure that the pump always has access to fluid while running, the vessel or sump on the inlet side of the pump must never run out of fluid while the pump is active. Level sensors or a float switch can be installed in the fluid chamber ensuring that the pump is turned off in the event there is no fluid. Another way of protecting the pump is to fit a dry running device, this will turn the pump off if it detects that no fluid is entering the pump. If you think that dry running is inevitable, then please speak to us and we will try to select a more suitable pump for your application.
A pump must be primed in order to operate correctly, this means that the pump casing and inlet pipe must be filled with fluid and the air removed before operation. This needs to be done manually by the pump operator for a non-self-priming pump each time the pump is used to avoid damage from dry running. A self-priming pump removes these issues by completing the priming process automatically. The air is removed from the inlet pipework and pump casing when the pump is activated. Self-priming pumps are particularly useful for installations with a suction lift on the inlet side of the pump, the pump will draw the fluid up the pipework by creating a vacuum and removing any air that is present. In ideal conditions, a self-priming pump can lift fluids up to around 8m on the inlet side, however this figure is affected by fluid viscosity, pipework bore and other installation conditions, therefore this figure can be much lower from case to case. Allowances must also be made for wear and tear; suction lift capabilities will be much lower for older and worn pumps.
Please be aware that the figures displayed relate to the largest pump from this range of products, not specific models. For details on viscosity for specific models, please refer to datasheets or contact a member of our sales team.
A clear picture of the pump system is required to make an accurate selection. The main pieces of information required include; a description of the application, bore of pipework, the fluid, viscosity, size and type of solids, flow rate and pressure/head. With these pieces of information, a pump can be sized correctly to ensure it delivers the required flow rate and pressure and that is also operates at its best efficiency point to lower lifetime costs. Knowing if the pump is running intermittently or continuously also allows the correct motor speed to be selected. For instance, a pump running continuously 24/7 will require a slower speed motor rather than a full speed motor. Running the motor slower and oversizing the pump will reduce wear of the motor and the pump, therefore lowering maintenance costs during their lifetime.
An integral bypass is designed to protect the pump and system from overpressure for small periods of time. It is typically set to around 10% higher than the working pressure, it will open and recirculate the fluid inside the pump head when the set pressure is achieved. An integral bypass is only a temporary solution and cannot operate indefinitely, an additional external bypass that runs back to the fluid source is always recommended as a more permanent solution.
ATEX is an abbreviation of “Atmospheres Explosibles”. It is a regulation set out by the European Union to ensure the safety of products that are used to handle flammable products or are installed in environments containing flammable gases, vapours, mists or combustible dusts. For instance, if the pump is being installed in an explosive environment, then only the motor needs to meet the Atex standard stopping it from causing a spark during operation and igniting the atmosphere. However, if the fluid being pumped is flammable, then the pump will also need to meet Atex standards to ensure that no sparks are caused inside the pump itself when the fluid goes through it. It is crucial that an Atex rated pump or motor are used for applications involving explosive environments or flammable fluids, using a non-Atex pump or motor in these situations is extremely dangerous and contravenes health and safety standards.
NPSH is an acronym for Net Positive Suction Head. NPSH measures the absolute pressure present in a fluid.

There are two main ways that NPSH is expressed in a pump system

NPSHa - This is the amount of Net Positive Suction Head available at the pump inlet. NPSHa demonstrates the amount of pressure acting on a fluid as it enters the pump. This measures the amount of pressure between the liquid staying in its current state and forming vapour bubbles (beginning to boil).

NPSHr - This is the amount of Net Positive Suction Head that the pump requires to operate without experiencing the damaging effect of cavitation, thus causing a dramatic reduction in pump performance.

It is very important to pay attention to these values when making a pump selection. Selecting a pump that requires more NPSH than is available in your system will cause fast and long-lasting damage to the pump and thus you will incur large repair costs and downtime.