About Industrial Application Of Internal Gear Pumps
Internal Gear Pumps can pump fluids of almost any viscosity, but for thicker materials, the speed must usually be reduced. They are not suitable for materials containing solids because they can cause premature wear. Internal gear pumps are self-priming and can be used for low NPSH applications. They usually provide smooth and continuous flow. In theory, at least they are bidirectional. They can provide individual or combined fluid power systems in series design.
Internal gear pumps have a wide range of applications in many industries: food manufacturers use them to deliver thick pastes and seasonings; the petrochemical industry deploys them in high-pressure metering applications, and engine manufacturers use them for oil transportation. They are used as delivery pumps. Special designs can be used for aerospace applications. The hydraulic pump should meet the SAE bolt hole requirements.
In the early 1990s, automobile engine manufacturers switched from external gear pumps to internal gear designs, including cycloid and two-tooth differential. The crescent type is particularly suitable for delivering large amounts of liquid at low speeds. As the distributor-based ignition system and associated camshaft gears disappeared, some of the pumps were driven directly from the camshaft.
Internal gear pumps can be manufactured for hygienic design of food, beverage and pharmaceutical services. The rotor can be suspended, supported by a single bearing or a pair of bearings outside the housing, and provides various seals. These internal pump components can be accessed through the cover plate so that sterilization can be performed directly. Can provide tight connection and no seal design.
Gerotor's geometry can be designed according to inventory or customized according to customer requirements. The viscosity of the fluid to be pumped will affect the backlash of any given cycloid pair or secondary cycloid. Although it is usually an internal component that drives the outer ring, special designs can be used where the outer ring is driven. Generally, the fewer lobes, the higher the speed. The more lobes, the smoother the flow. Although a three-lobed rotor can be used in theory, it is not practical for several reasons, so the four-lobed rotor is set as the minimum starting point.
Compared with external gear pumps, the initial cost of internal gear pumps is usually higher, but the wear rate is lower, which can extend the service life. Although advanced cycloidal gear manufacturing methods make these pumps extremely adaptable and cost-effective, the design is more complex. One disadvantage of internal gear pumps is the overhanging load imposed on their bearings. However, this makes disinfection simple.
A common disadvantage shared by all gear pumps with other positive displacement pumps (such as vane pumps) is that they cannot provide variable flow at a given input speed. In the case of this requirement, a workaround is to use a drive with speed control function, although this is not always a feasible solution.
Finally, although rotary displacement pumps can pump water, their main application is in oils and viscous liquids, because it is necessary to maintain the lubrication of friction surfaces and it is difficult to seal very thin fluids. For most water-based applications, centrifugal pumps or dynamic displacement pumps are the clearer choice.
Zhejiang Yongling Hydraulic Machine Co , Ltd . is a professional China manufacturer and supplier of internal gear pumps and Vp Series Variable Displacement Vane Pumps . Our products are widely used in cutting, plastics, forging, engineering, leather, pressure, metallurgy, agriculture, transportation machinery and machine tools, hydraulic stations, automatic production lines, etc. Welcome to buy: https://www.china-vanepump.com/product/internal-gear-pumps/