Things You Should Know Before Buying A Dry Vane Pump
A dry vane pump is a positive displacement pump for gases and liquids for suction or pressure applications. It consists of a hollow cylinder (stator) in which another cylinder (rotor) rotates. The axis of rotation of the rotor is arranged eccentrically to the stator, the rotor touches the inner wall of the stator between the inlet and outlet ports. This point is a separating point of the suction and pressure chamber. Vacuum pumps according to this principle are often called oil pumps in chemical laboratories because they usually require large quantities of lubricating oil. However, the dry vane variant does not need an oil change, and hence, saves costs.
How Does A Dry Vane Pump Work?
In the pumps, there are one or more rotors, usually with radially arranged guides. In these guides sit the rotary valves. These sliders divide the space between the stator and rotor into several chambers. To compensate for the change in distance between the rotor and the stator during one revolution, the rotary valves can move in the guides. They are usually pressed by a mounted in the bottom of the slot spring against the inner wall of the stator. To ensure lubrication, usually, a small lubricating oil is generated within the pump through which the rotary valves run. Therefore, the pump always promotes a small part of the lubricant. This is usually deposited in the exhaust tract and fed back to the lubricant reservoir. Lubricant-free rotary vane pumps are also available.
Constructive and Functional Details:
Simple vacuum pumps are built virtually exactly as shown in the schematic drawing. In case of a dry vane pump, there is a variable volume, which has no connection to either the inlet or the outlet opening. The pumped medium is diluted during pumping in the closed conveyor track and recompressed. When used as a vacuum pump, however, a gas is promoted, which is usually diluted. The work needed for diluting or compressing the medium in the delivery tract is therefore small so that they can be taken in favour of a simple construction of the vacuum pump while purchasing. For other applications, in particular, the conveyance of incompressible media such as liquids, the remedy must be provided by constructive measures – usually by increasing the inlet and outlet opening:
- Inlet opening should be up to 90 °
- Outlet opening should be approximately higher than 270 °
Advantages of A Dry Vane Pump:
These pumps have the following benefits:
- Low Volume Flow Pulsation: This increases efficiency and minimizes chances of failure.
- Medium Noise Emission: The operations do not have any disturbing effect on the surroundings.
- Multidirectional: These pumps can work in both directions
- Flexible Volume: The delivery volume is adjustable and can be changed as per requirements
- Cost Effective: A dry vane pump is highly economical and saves costs as it does not need lubricant liquid.
- Excellent vacuum features the vacuum functions efficiently. As siding contact is involved, this type of pump is especially great for thin liquids.
A dry vane pump has a mechanism that avoids contact between its different internal parts. This removes the need for lubricants. Also, the pumps can compensate pressure and are highly durable. However, they are most suitable for liquids with low viscosity, like alcohol, solvents, etc. and gases like propane. Though they are a bit high priced as compared to other types of pumps like the variants which need lubricants, in the long run, they can save you a lot of money due to low maintenance costs, high durability and the lack of need for lubricants. You should look for a reputed company which specializes in this type of pumps.