Gear pumps - Overview
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Classification
Gear pumps are positive displacement pumps,
There are various designs, primarily external gear pumps.
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Construction
Pump head with gearwheels mounted on both sides. Drive unit usually consisting of coupling and gear motor. However, there are also other designs such as direct-coupled gear pumps, often in combination with a magnetic coupling.
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Functionality
Two synchronously rotating gear wheels, with the gear wheel connected to the drive shaft driving the other, convey the liquid medium horizontally or vertically, depending on the orientation of the pump head. The gear wheels are lubricated by the medium.
The size, module and design, in combination with power and speed, determine the flow rate. The flow rate is variable by speed control or bypass solutions. The delivery pressure is determined by the back pressure on the pressure side of the system and is limited by the power limit of the machine and the gap losses.
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Power range
Pressure: up to 120 bar
Flow rate: 0.01 to 300 m^3/h
Viscosity: up to 0.7 - 150,000 mPas
Temperature: - 60 to 450 °C
Power: 200 kW
Solids content: up to X % (non-abrasive - soft solids)
Solids size: variable (depending on pump type)
Suction height: up to 6 m
Heating: electrical, thermal oil, steam, water
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Applications
Gear pumps are suitable for pumping primarily clean, non-abrasive media. As positive displacement pumps, these machines are suitable for pumping low to high viscosity liquids. Different gear wheel shapes ensure optimum delivery of the liquid
Gear pumps are self-priming and can also be used as metering pumps.
In the field of positive displacement pumps, gear pumps are considered to be low-pulsation/free, which is decisive for many dosing processes.
By using external bearings and special material combinations, non-lubricating media can also be pumped.
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Sealing technology
Stuffing box packing, lip seals, single-acting mechanical seals, double-acting mechanical seals, magnetic coupling (also possible heated)
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Materials
Grey cast iron, cast steel, steel, stainless steel, Hastelloy, Duplex, Super Duplex, bronze, aluminium, titanium, tantalum, plastic, other special alloys on request
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Keywords
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