Difference between a vane pump and a gear pump

You may have heard of a vane pump and a gear pump and had an idea what it is about. This article seeks to shed some light on the matter. Keep reading for more details on the differences between these two types of pumps:

A Gear pump uses gears and a vane pump uses vanes

In high-pressure applications, gear pumps are more preferable than vanes which should be used in low-pressure. Conversely, vane pumps also operate at higher pressures.

Flow rates of liquid are increased by the use of gears in a gear pump and vanes in vane pumps. A gear pump is constructed with several interconnecting gears rotating at different speeds around their axes. These gears patterns allow fluid to pass through many gears rather than only one when it moves from one tooth to another in a row. By this way there is more flow for each gear because it has access to more volume.

Vanes are moved towards each other and apart so as to enlarge the area through which fluid flows between them in vane pumps. Nevertheless, the overall structure of a vane pump resembles that of a gear pump, except that instead of using gears; it employs two vanes that oscillate back and forth thereby creating an enlarged section for fluid passage between them.

Vane pumps can be used with more viscous fluids than gear pumps

The special feature of vane pumps is that they can pump higher viscosity liquids like honey, molasses and oil. Additionally, their flow rates are much greater than other kinds of pumps. Vane pumps are best suited for high pressure or high viscosity liquid pumping applications. Besides, unlike the other types of pumps, they do not require lubrication or seals hence easily cleaned.

Usually, vane pumps have a larger diameter than gear pumps but the overall volume is approximately that of a gear pump. Hence it means that these types will be able to transport more material at higher speeds and pressures compared to gear pump.

Vane pumps are generally more efficient at low speeds because they depend on vane rotation rather than gears or other mechanisms which may become less effective with time.

Vane pumps run quieter than gear pumps

That is why its shaft is off-centre and can be installed in a larger diameter housing which minimize the noise of the motor. The other cause of noise could also be due to vane pumps with smaller diameter housings which results into excessive vibrations that add to the noise level. Nonetheless, even other kinds of pumps such as impeller and centrifugal pumps are not as quiet as those of vane type.

In addition, there are situations where it is necessary to use machines that do not produce a lot of noise like vane pumps or when other types of motors or equipment may generate hums or vibrations. Moreover, for high pressure industrial processes without continuous power supply like that furnished by gear pump, we find these kinds of devices very useful.

Vane pumps can produce much higher pressure than gear pumps

Gear pumps can be used to power bigger systems and applications that demand a high flow rate. They have several merits including the availability of high head (pressure) at low flow rates. Additionally, they are highly efficient hence suitable for pumping concrete where they provide a high head at a low flow rate.

Compared to gear pumps, vane pumps can generate much higher pressure. These use large diameter shafts with several vanes revolving around them which enable it to rotate its pump shaft faster than gear pump hence achieving more pumping speed without compromising on efficiency.

Vane pumps have lower volumetric efficiencies than gear pumps

Gear pumps are more efficient because they rotate at a constant speed, unlike vane pumps. After installing a gear pump in your system and it starts to spin you will not see flow increase until it reaches its maximum rotational speed (which is slower than an impeller).

Vane pumps have fixed volumetric efficiencies that can not be changed from the manufacturer’s spec. In other words, when you increase system flow you may get less throughput per revolution of the pump.

Gear pumps are generally less expensive than vane pumps

The explanation as to why gear pumps are more efficient is that they can produce the same amount of horsepower at a lower cost. Gear pumps differ from vane pumps in the sense that they can be utilized for both low and high pressure applications, and are constructed with better materials than vane pumps. In general, the cost of vane pumps is higher than gear ones but there are some things at which vane pump has an advantage, for instance it can operate at higher pressures.

Vane pumps are versatile and their application can be anywhere from hydraulic power to chemical industry

Petrochemical industry had not been using them much until recently, but now they are used extensively in this area. Apart from traditional uses, vane pumps are also serving as a motor for windmills and other machinery requiring high output torque at low speeds.

Vane pumps have different forms such as axial piston vane pumps, radial piston vane pumps, centrifugal vane pump etc. Axial piston pump and radial piston pump are the most commonly used types of vane pumps.

Axial Piston Pump: This type of pump is typically employed for water supply or waste water applications where the discharge pressure may be relatively high and the flow rate is relatively low. It consists of an enclosed rotor with several vanes aligned parallel to it. Arrangement of these vanes makes efficient distribution of flow into the discharge line while maintaining its velocity in vertical direction by applying counter-current flow technique.

Vane pumps are better for stationary applications, but gear pumps are best for portable equipment

A gear pump is a device that moves fluid from one place to another by means of a rotating shaft. These are made in a way that allows them to work at low speeds and high pressure values. The use of disc wheels or gear wheels enables the turning axis of a gear pump. Vane pumps are suited for stationary applications, whereas gear pumps are ideal for portable equipment.

A vane pump consists of two main parts; these are impeller and casing. The impeller has got two vanes that rotate around it and it is mounted on the shaft of the pump. This type of a pump has flow control through changing size vanes during rotation. A vane pump can operate at any speed, but they will give you more power once you make them spin faster because their flow rates are usually highest at higher speeds.

The only moving part in a gear pump is its shaft itself. We have not introduced other internal elements to affect how it works so if everything goes as planned, you can turn it around as fast as you want.

This blog post tries to provide brief explanations about geared and vane pumps; hopefully these few words may act as your guide in future.A happy reading!

Difference between a vane pump and a radial piston pump