A pair of gears with many teeth external to the gear and called an external gear pump in gear pumps or a few lobes in lobe pumps is demonstrated in fig. The gear pump manufacturing gpm worldwide office is located in cape town south africa and has specialized in the manufacture and assembly of sae mounted cast iron hydraulic gear pumps, piston pumps and associate components since 1985. Fluid, drawn into the pump, is enclosed within the cavities of its rotating gears and transferred to the discharge. High pressures high viscosity fluids are able to be pumped over long distances using external gear pumps, thanks to their ability to handle high pressure applications selfpriming capabilities gear pumps benefit from excelling selfpriming capabilities thanks to their rotating gears evacuating any air in the suction line, and forcing the liquid into the pump inlet. Gear pumps are the most popular type of positive displacement pump. There is no doubt that the gear type pump is the most widely used design in hydraulic systems. Many external gear pumps use journal bearings to support the rotating shafts.
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. To prevent leakage caused by the common crowning effect, permco shapes gears rather than hobbing and shaving them. Design analysis and testing of a gear pump research inventy. While they are often used on thin liquids such as solvents and fuel oil, they excel at efficiently pumping thick liquids such as asphalt, chocolate, and adhesives. Small gear pumps usually operate at a speed between 1,700 rpm and 4,500 rpm, and larger models most often. The results show that the curve of trapped volume is similar to a parabola and the pump designed with a large number of teeth, module, and pressure angle easily. Because seal leakage is the most frequent cause of pump downtime, the sg series minimizes shaft. Jul 18, 20 external gear pumps work external gear pumps are similar in pumping action to internal gear pumps in that two gears come into and out of mesh to produce flow. Apr 20, 2016 external gear pumps under the following two cases. Failures of the front pump are, in fact, limited to just a few specific modes such as overheating, overpressurization, shaft.
Gear pumps are invariably of fixed displacement type, which means that the amount of fluid displaced for each revolution of the drive shaft is theoretically. Failures of the front pump are, in fact, limited to just a few specific modes such as overheating, overpressurization, shaft failures, contamination and cavitation. Design of a hydraulic pump for construction with additive. Sg series pumps were designed to ensure reliability in industrial process applications. Internal gear crescent internal gear pump design for high viscosity fluids. The useful viscosity range of an internal gear pump is from 1cps to over 1,000,000cp. One gear is driven by the motor and in turn moves the other gear. External gear pumps can come in single or double two sets of gears pump configurations with spur shown, helical, and herringbone gears. This investigation can be an essential and simple tool to design high performance gear pumps. The pump is so named because it has two gears that are sidebyside or externalto each other. The external gear pump consists essentially of a pair of gears supported in bearing. Bathasme 2020 symposium on fluid power and motion control. You can interact with actual flash animation at the link given above. Proceedings of the bathasme 2020 symposium on fluid power and motion control.
Installation, operation, maintenance user instructions user instructions 71569246 2167be1. The outer gear of this pump rotates concentrically in the casing and is coupled to the driver. Design parameter simulation parameter pump layout window cadfem interface september 2011 14 pump. External gear pumps can be divided into external and internal gear types. This design does have more mechanical sealing faces that would normally result in increased losses however, the products tend to be higher priced that external gear pumps with the extra cost going to the higher quality manufacturing required. In order for these bearings to work, a minimum speed is required depends upon pressure of the pump. The design principles and the performance of hydrostatically loaded wear end plates in three highpressure external gear pumps were examined experimentally while the pumps were running under. Pdf flow characteristics of external gear pumps considering. The long life and nonpulsing flow of the external gear design are combined with the magnetically coupled, leakfree, seal less construction. The external gear pump is a positive displacement pd type of pump generally used for the transfer and metering of liquids.
Many details are similar to the external gear pump details above. Calculation of theoretical torque and displacement in an. First, the internal gear pump without crescent is described below. In addition to imposing limits on the operational speed, in many cases, the bearings determine the maximum pressure the pump. 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. Internal gear pumps internal gear pumps are exceptionally versatile. Power group of the university of parma has implemented a numerical code for the simulation of external gear pumps and motors. Our design gear pump generate noise level between 90db to 100db. External gear pump gd5 series eaton hydraulics pdf.
Gear pumps spa industrial pumps star pump alliance. Usually, these pumps are designed to work over a wide range of speeds and high delivery pressures as positive displacement units in hydraulic. Also, the effect of gear teeth radiusteeth tip length on the pump performance has been studied in various working pressures within a case study. Pdf in this work, the authors have developed a mathematical model that simulates the run in of external gear pumps, as an useful tool in the. China email protected li sun school of mechanical engineering dalian jiaotong university, dalian, p. Further configuration variants are given by different flanges, shafts, valve arrangements and multiple pump combinations. A design procedure for multistage external gear pumps fluid. This design does have more mechanical sealing faces that would normally result in increased losses however, the products tend to be higher priced that external gear pumps with the extra cost going to.
Investigation of leakage within an external gear pump with. In this last case the authors have also tested a new boundary condition for maintaining a good. The simulation tool hygesim a entire simulation of external gear machines pumps motors considering main physical phenomena tool versatile, useful for verification design purposes main features of the hygesim hydraulic gear machines simulator. An external precision gear pump is usually limited to a maximum working pressure of 210 bars 21,000 kpa and a maximum speed of 3,000 rpm.
External gear pumps with spur gears are classified as low. Internal gear pumps use a gear within a gear design. A vast knowledge of magnet, pump, and motor technology is utilized in the design, manufacturing, and application of our magnetically coupled pumps. Nov 11, 2020 the paper presents a cfd model of an external gear pump.
Their objective is to start the engine, to provide take off flow at the required pressure and to prime a fuel system. Hydraulic gear pump and motor failure analysis and repair. Two identical gears positioned side by side, rotating into one another. Pdf cfd model of an external gear pump researchgate. In these pumps water enters axially and is discharged by the rotor into a discharge pipe. It is simple in construction, reliable in operation and the most costeffective way of. Gear pumps are often used in pumping relatively viscous liquids, such as some viscous liquid hydrocarbons, liquid fuels, lubrication oil pumping in machinery packages, hydraulic units and fluid power transfer units. Rotary pumps use a variety of means to generate flow. What should we consider technically if we have to run our external gear pump for soft water with inject dye liquid. Gears permco pumps are cut in our own plant to extremely close tolerances. Displacement d the displacement of a rotary gear pump is the volume displaced during one complete. External gear pump working animation with detail explanation. Heisler et al 2 used the computational fluid dynamics cfd to better analyze the effect of modifying the design of an existing external gear pump. External gear pump overview michael smith engineers.
Apr, 2019 as a result, the pump overall performance increases with smoother outflow. Purdue university activities on gear pumps motors project 1. Albany gear pumps are available in many configurations, whilst they may look the same, there may be differences from one pump to another, and therefore supplementary instructions can be supplied. The fixed displacement gear pumps utilized by alamo industrial are of a proven design and will easily provide exceptional service for the life of the machine. Modeling and simulation of gear pumps based on modelicamworks. Scribd is the worlds largest social reading and publishing site. External gear pump design for hydraulic power applications. They have an impeller which rotates in a casing of a special shape. The objective of the study was to design a hydraulic pump suitable for additive manufacturing and thereby prove. A typical application of this is in the supply of hydraulic oil in power steering systems.
Pdf an investigation of external gear pump efficiency. A design procedure for multistage external gear pumps. To get the best from the pump, carefully read and understand this manual before installation and startup. The rotating gear carries the fluid from the tank to the outlet pipe. It is noisy in operation than either vane or piston pumps. The pump is composed of a driving gear an external tooth gear placed inside and a driven gear an internal tooth gear placed outside. Nasgp external gear pump nasgp 300 a 8 a 9 h 2 r e10 model code how to order port type. This work is focused on the optimization of the pump design with particular. Parker gear pumps power dense design produces an energy savings and provides oems a marketable advantage to improve revenues. In addition to imposing limits on the operational speed, in many cases, the bearings determine the maximum pressure the pump can operate at. Rotary pumps are usually classified according to the type of element that transmits the liquid, so that we speak of a gear, lobe, vane, or pistontype rotary pump. In this study, a mathematical modeling of gear pairs is deduced based on the meshing theory and a complete set of mathematical equa. To investigate the fluid flow phenomena that occur in external gear pumps, one of the commercial cfd software packages was selected.
Multiport gear pump design based on virtual prototyping technology xiaoyang yu school of mechanical engineering dalian jiaotong university, dalian, p. Grp operating principle delivery port cover plate mid plate base plate inner rotor outer rotor. Useful information on gear pumps michael smith engineers. 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. Hydraulic gear pump and motor failure analysis and repair guide. Positive displacement pumps allow liquid to flow into an open cavity trap the liquid in the pump transport liquid from the suction to discharge port mechanically force liquid out of the pump. China email protected abstract in this paper, the familiar structures of multiport gear pump are analyzed, and designed based on. Design and cfd analysis of external gear pump abdul wahab1 capital university of science and technology islamabad pakistan abstract gear pumps are commonly found in turbine engine high pressure part of fuel system. External gear pump free download as powerpoint presentation.
Centrifugal pumps develop pressure by increasing the velocity of the liquid liquid is literally flung out of the cutwater. Liquids containing solids are not really suitable for gearpumps unless the particles are really small. Gear pumps with integral valves in order to reduce external pipework it is possible to incorporate a flowcontrol valve or pressurerelief valve in the rear cover of the gear pump. Types of gear pump internal, external,gerotor, lobe pump.
Construction the external gear pump consists essentially of a pair of. Thus the discharge per unit revolution is a function of the size of the gears and the number of teeth. Gerotor pumps for automotive drivetrain applications. Gear pumps d series and xd series gear pumps technical. Modeling and simulation of gear pumps based on modelica. Gear pumps are less expensive but limited to pressures below 140 bar.
One of the gears is coupled with a prime mover and is called as driving gear and another is called as driven gear. You immediately receive a project drawing pdf format if. In this video we are going to see how external gear pump works. They can manage low viscosity liquids like alcohols, solvents or liquid gases as well as medium and high viscosity liquids like polymer melts, gumbase or rubber. Figure 3 shows another typical structures here n2,n3,n4. The displacements are graded by different gear widths. Highquality, heattreated alloy steel integral gears and shaft 2. External gear pump design, advantages and disadvantages. This nomenclature differentiates it from an internalgear pump, which has one gear positioned inside the other.
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