The working principle of the external gear pump is illustrated in figure 1. The fluid is been trapped in between the gap if the gear teeth and the casing and gets carried to the outlet and not through the engaging portion. A magnetic drive pump uses a balanced magnetic field to create the rotation of the fluid impeller. Liquid flows into the cavities and is trapped by the gear teeth as the gears continue to rotate against the pump casing and partition.
The gear pump working principle involves the rotary action of two gear toothed rotors which unmeshes at the suction end thus drawing in liquid carries liquid along the gear teeth and meshes at discharge end thus forcing the liquid out against discharge line pressure. A three screw pump operates on the same principle of intermeshing screws as the two screw pump, and can be configured as a double suction pump technically, a six screw pump. The trapped fluid is moved from the inlet, to the discharge, around the casing. Gear pump working, construction, maintenance marinersgalaxy. Selection of a positive displacement pd rotary pump is not always an easy choice.
Because internal gear pumps have only two moving parts, they are reliable, simple to operate, and easy to maintain. The working of the gear pump starts from receiving of fluid at the inlet. The close tolerance between the gears acts as a seal between the suction and discharge ports. Pumps can be classified into three major groups according to the method they use to move the fluid. Indicating lights check to make sure they are working properly. Basics concepts of operation, maintenance, and troubleshooting, part i. Each screw pump operates on the same basic principal.
Many external gear pumps use journal bearings to support the rotating shafts. As the rotor gear begins to turn, the idler gear rotates with the. The teeth are shaped so all of the teeth of the inner gear are in contact with some portion of the outer gear at all times. Though the construction, shape and design of gear, vane and globe pumps are a bit different, they fall under the same category of rotary pumps. The theoretical flow ripple of an external gear pump. Hydraulicspneumatics com sites hydraulicspneumatics com files uploads 2015 02. Liquid enters the suction port between the rotor large exterior gear and idler small interior gear teeth. The qxv unit is an internal gear pump for lowviscosity flu. The gear pumps are basically positive displacement rotary pumps which helps you to transfer liquid or fluid by using its gears. As the rotor gear begins to turn, the idler gear rotates with the teeth beginning to mesh.
Pg330 pg331 tutorial01 cast iron gear pump salami spa duration. Internal gear pumps can be used up to a continuous pressure of 315 bar 4550 psi depending on the frame size. Types of gear pump internal, external,gerotor, lobe pump. For double chamber vane pumps, the process of filling the chambers suction and emptying is in principle the same as for single chamber vane pumps. Externalgear pumps can be divided into external and internalgear types. Mar 01, 2000 however, the external gear pump uses two identical gears rotating against each other one gear is driven by a motor and it in turn drives the other gear. When using equivalent pump speeds, gear pumps have comparable shear imparted compared to progressive cavity pumps. Annual tests at least once a year, test the pumper to determine if it is capable of meeting the. Gear pumps galtech group 2 start pumps 12 tooth gears and consequent decrease in noise levels. The fluid is carried around the outside of the gears to the outlet side of the pump. Installation and service instructions excellence at work. In an internal gear pump, the rotor supports on one or two bearing and the design of the pump is bulky that makes it inefficient to work on high specification models. We will also learn how is the working of screw pump different from that of other types of pumps. Working mechanism of a centrifugal pump a centrifugal pump is one of the simplest pieces of equipment in any process.
Each individual pump is preset for rear connection to one or more pumps by interposition of the appropriate coupling flange. Pumps operate by some mechanism typically reciprocating or rotary, and consume energy to perform mechanical work moving the fluid. The rotating gears develop a liquid seal with the pump casing and create suction at the pump inlet. Gear pumps use the actions of rotating cogs or gears to transfer fluids. Liquid travels through the pump between the teeth of the gear withina gear principle. What is the most important application for internal gear pumps. Rexroths complete line of hydraulic pumps serve virtually every industry in manufacturing and technology applications such as railway engineering, chemical process plants, power and environmental engineering, automotive engineering, plastics processing machinery, paper industry, presses, test rigs and simulation systems, marineoffshore. The term positive displacement for gear pumps describes the fixed amount of fluid they move for each revolution. Jan 02, 2017 external gear pump flow through stephen stott. An external precision gear pump is usually limited to a maximum working.
External gear pump free download as powerpoint presentation. An internal gear pump works on a similar principle except the two linking gears sizes are different with one revolving within the other. When the impeller rotates at high speed, the impeller drive a rotation of the liquid between the blades, due to centrifugal force, the liquid thrown from the center of the impeller outer edge of the impeller flow rate can be increased to 15 25m s, the kinetic. The pump head is now nearly flooded, just prior to forcing the liquid out of the discharge port. Operates a gear within a gear principle, whereby one gear the idler is positioned inside another gear the rotor. This is a function of the fluid viscosity, clearance between internal components, friction between mating components, and other variables. The vacuum is created in the vacuum pump by using a liquid seal,the most commonly used liquid sealant is water.
The three screw design utilizes a centrallylocated primary screw, or power rotor. I am sure that this book will serve the needs of electrical engineers working in the field of general services. Two identical gears positioned side by side, rotating into one another. Shipment shortages, checked against the transport documents, should be reported.
A gear pump uses the meshing of gears to pump fluid by displacement. Internal gear pump with detail explaination and animation in this video, you will learn about an internal gear pump working process. This pump principle features a compact design with particularly high energy density. We have medium pressure and highpressure pumps in our product portfolio.
Displacement d the displacement of a rotary gear pump is the volume displaced during one complete. The qxv unit is an internal gear pump for lowviscosity flu ids. One gear is driven by the motor and in turn moves the other gear. Thus, the pump has only two moving parts, the rotor and the idler gear. Flange and cover in aluminium or on request, cast iron. Worked out criteria and their boundary values allowed the defect classes creation and the defectsymptom diagnostics relation. Hi guys, this is an animation video on the working of crescent type pump or called as internal gear pump, charging pump etc. Liquid travels through the pump between the teeth of the gear withinagear principle. Gear pump is straight forward and simple in their working. Internal gear pump design for automotive oil pumps.
The chamber of the pump is divided into a set of control volumes cvs, whose effective volumes change along with the rotation of the gears. Liquid enters the suction port between the rotor large exterior gear and idler small interior gear. The pumping capacity of the internal gear pump is less in comparison to the external fear pumps. The gear mounted to this shaft driving gear engages the other gear driven gear fluid on the inlet side flows into and is trapped between the rotating gear teeth and the housing. Unlike a traditional centrifugal pump which has a direct drive connection between impeller and motor, a magdrive pump eliminates the direct drive mechanism and replaces it with a magnetic field. Numerous improvements have been made to the straightforward and robust design. S volumetric efficiency up to 98% by multistage principle. An internal rotary gear pump employs a positive displacement principle. As the rotor gear begins to turn, the idler gear rotates with the teeth beginning to mesh accordingly. When the fluid moves forward due to the vacuum created behind the teeth of the two gears, it starts getting trapped into the teeth of the gears. The gg series pumps use the internal gear design pumping principle see figure 1 to perform the positivedisplacement pumping action desired. One rotor of internally cut gear teeth will mesh with one externally cut gear.
In an internal gear pump fluid enters int the suction port between the rotor and idler it is a small interior gear teeth. An internal gear pump uses two gears to move fluid. It moves a fluid by repeatedly enclosing a fixed volume using interlocking cogs or gears, transferring it mechanically using a cyclic pumping action. Fluid shall be carried between gear teeth and shall be displaced when the gear teeth mesh. Pdf gear pumps represent the majority of the fixed displacement machines used. Gear pump working principle animation video a gear pump is a rotary type of positive displacement pump.
The fluidotech ig series positive displacement gear pump has been designed to handle viscous fluids with impurities in suspension and temperatures up to 200 c 392 f whilst delivering a smooth flow. The internal gear pumping principle was invented by jens nielsen it uses two rotating gears which unmesh at the suction side of the pump to create voids which allow atmospheric pressure to force fluid into the pump. Above figure shows construction exploded view of a typical flat plate type vacuum pump. Maintenance and service manual selfpriming internal gear. The gear pump is simple in its operating principle. An internal gear pump operates on the same principle but the two interlocking. The prv can be piped back to the suction side of the pump or into the supply tank.
They typically consist of a northern heavy duty gear pump, electric motor, shaft coupling, and coupling guard, mounted on a unit base. A directdrive gerotor motor consists of an innerouter gear set and an output shaft fig. Roots pumps, screw pumps, claw pumps or at the pumps high pressure. A pump is a device that moves fluids liquids or gases, or sometimes slurries, by mechanical action. Screw pumps are the only type of pumps which are different from other rotary displacement pumps because of the axial flow of the fluid through their pumping elements. The three screw design utilizes a centrallylocated primary screw, or power rotor, which intermeshes with two secondary screws, or idler rotors.
Advances in the manufacturing process have made it poss. This pumping principle produces a pulsating flow, rather than a smooth flow. External gear pump overview michael smith engineers. Gear pumps make good chemical additive dosing pumps provided material compatibility issues are addressed. Centrifugal fire pump principles of operation, inspection tests and troubleshooting guide. When using a gear pump a pressure relief valve must be fitted to protect the pump if deadheaded against a closed valve or blockage. Tandem and multiple pumps are available worldwide in more than variants. Note that if fluid slippage is substantial, the pump is not operating properly and.
Some internal gear pumps have an additional, crescentshaped seal shown above, right. Gear pumps are compact, high pressure pumps which provide a steady and pulseless fluid. Useful information on internal gear pumps what is an internal gear pump. Abstract the paper comprises research results of the gear pump typical failures and their connection with symptoms observed during the pump working. Construction, working, operation and maintenance of liquid. Most pd pumps can be adapted to handle a wide range of applications, but some types are better suited than. Sep 11, 2014 internal gear pump overview internal gear pumps are very versatile, with the ability to pump many different types of fluids at a wide range of viscosities and temperatures. It is a hydraulic machine which converts mechanical energy into hydraulic energy. The qx pumps are the 5th generation of bucher internal gear pumps, which have proven themselves in thirty years of service around the world. Gear pump components pump unit assembly northern pump is a full service gear pump manufacturer. This is an animation video on the working of an internal gear. As the gears come out of mesh, they create expanding volume on the inlet side of the pump.
As the gears come out of mesh on the inlet side of the pump, they create an expanded volume. It has more than two internal gears which create vacuum pressure to push the fluid in the pump. The pump features a casing in which a dual gear an outer rotor gear and an internal idler gear and crescent assembly is housed. A gear pump is a type of positive displacement pd pump. It may be calculated from the physical dimensions of the gears, or it. A pump may be driven by hand, by an electric motor, by an internal combustion engine, or by hydraulic or pneumatic means.
The arrows indicate the direction of the pump and liquid. All content contained herein is subject to change at the companys discretion without notice. Theyre also birotational, meaning that the same pump can be used to load and unload vessels. Gear pumps are positive displacement rotary pumps that transport liquids using rotating gears. In the analysis that follows, the numbers of teeth on each gear will be allowed to vary and therefore, in general, the two gears will not be identical. Viking pump pump innovations in liquid handling since 1911. They come in many different sizes and designs and a firefighter needs to know how to operate the pump efficiently at all times. By using several pump stages connected in series, pressures to 250 bar can be developed with high efficiency at viscosities of around 1 mm2s. The impeller of a typical radial flow pump and the flow through a radial flow pump are shown in figure 6. The crescent shape divides the liquid and acts as a seal between the suction and discharge ports. The fluid in screw pumps moves between the screw threads and is displaced axially as the screws rotate and mesh. Screw pumps also falls in the category of rotary pumps and have the same mechanism and principle.
Jul 18, 20 the arrows indicate the direction of the pump and liquid, 2. Centrifugal fire pump principles of operation, inspection. Tooth profile, external gear pumps, mathematical models, control volume. Learn more about viking pump industry leader and innovator since 1911. A pump is a machine, powered by an external source, which imparts energy to a fluid or gas. Internal gear gerotor pump design for high viscosity fluids. Useful information on gear pumps michael smith engineers. We frequently build and assemble pump unit assemblies, or skids as they are sometimes called. The fluid travel through the pump between the the teeth of the gearwithinagear principle. Sep 05, 20 centrifugal pumps generally driven by the motor, before starting the pump, the pump and the suction pipe is filled with liquid. Some manufacturers produce gear pumps with higher working pressures and speeds but these types of pumps tend to be noisy and special precautions may have to be made. This seal forces the liquid out of the discharge port.
A rotor gear on the outside and a smaller, idler gear nested inside. Modeling and simulation of gear pumps based on modelicamworks. The working principle of gear pump the structure of the gear pump is very simple, that is, it is the most basic form of two dimensions of the same gear in a tight fit the shell body of a mesh with each other in the rotation, the shell of internal similar 8 glyph, two gear installed inside, outside diameter of gear on both sides and the shell and tight fit. Precise by design, they deliver accurate and repeatable performance, a smooth flow and a pressure up to 18 bar 260 psi. Pumps operate on the principle whereby a partial vacuum is created at the pump inlet due to the internal operation. These pumps are positive displacement pumps and anything drawn into them will be forced out. Each gear is supported by a shaft with bearings on both sides of the gear. Internal gear pump fluidotech ig series positive displacement internal gear pumps are designed to work in harsh environments, with unfiltered, abrasive fluids and in a wide temperature and viscosity range. Typically, gear pumps have efficiencies around 85%. A drive gear that is driven by a motor rotates an idler gear in the opposite direction. Gear pump manual original instructions albany pumps. What is a double chamber vane pump and why you need it. External gear pump overview external gear pumps are a popular pumping principle and are often used as lubrication pumps in machine tools, in fluid power transfer units, and as oil pumps in engines.
The gear pump is a precision machine with extremely tight fits and tolerances, and is capable of working against high differential pressures. Sep 07, 2019 liquid ring vacuum pump working principle. The positivedisplacement principle is well illustrated in the reciprocating type. Useful information on gear pumps what is a gear pump. Information on gear pumps including how gear pumps work, the main features. We model the whole working process of an external gear pump. Rotor and idler teeth mesh completely to form a seal equidistant from the discharge and suction ports. Flat plate type vacuum pumps have a port plate configuration rather than a cone, but the working principle is the same. Liquid ring vacuum pump working principle and pumping system. The straightforward and rugged construction guarantees long service life without the need for extensive maintenance. Back to basics w hen i left university, i found that i needed addi.
A screw pump is a positivedisplacement pd pump that use one or several. An internal rotary gear pump can handle fluids with a viscosity of 100,000cst. The arrows indicate the direction of the pump and liquid, 2. External gear pumps can come in single or double two sets of gears pump configurations with spur shown, helical, and herringbone gears. The working of all these pumps are based on the same principle, i. Gear pumps use toothed gears turning inside a close tolerance housing to drawin liquid and then squeezing it out ahead of them. Fixed displacement vane pumps hydraulic pumps and parts. The internal gear pump is nonpulsing, selfpriming, and can run dry for short periods. An internal rotary gear pump is typically specified for viscous fluids such as oils, bitumen, fats, syrups, chocolate and resins as the more viscous the product is, the more efficient the displacement aspect of the working principle becomes.
Experts in internal and external gear pumps, general pumps, and liquid handling. The qxv is being used with great success to pump aviation jet fuel, automotive fuels, paraffin oilkerosene, brake fluids, pentosin and. Design and per formance of gear pumps with a noninvolute tooth pro file. Scribd is the worlds largest social reading and publishing site.