Detailed information on Rexroth gear pumps of the AZPS series — shared by Autos

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Features of the Rexroth gear pump AZPS series: – Nominal pressure of 280 bar – Uses sliding bearings, making it suitable for heavy-duty applications – Drive shafts meet ISO or SAE standards – Multiple pumps can be combined together – Pipe connections: flanged fittings – Pressure fluctuations are optimized, thereby reducing noise emissions and vibration in the system – Enhanced design of the shaft and material used for the pump cover extend its service life – Consistent high quality is achieved through mass production – Various configuration options are available. Overview of the Rexroth gear pump AZPS series: An important function of external gear pumps is to convert mechanical energy (torque and speed) into hydraulic energy (flow rate and pressure)； External gear motors are exactly the opposite. These devices must have high efficiency to avoid generating unnecessary heat. This high efficiency is achieved through precise manufacturing processes and pressure-sensitive gap sealing. Moreover, in this low-noise silent pump, this double-flange principle helps to reduce flow pulsation by up to 75%. The sealed area of the gear pair, in combination with the rotation mode of the drive shaft, results in the flow characteristic curve shown in the left diagram (schematic). In a standard hydraulic pump, each time a pair of gears meshes, there is a pulsation on this characteristic curve. After adopting the double-flange structure, the flow pulsation of this silent pump was reduced by 75% – which in turn reduced the flow pulsation on the components in the downstream system – with the new frequency being equal to twice the fundamental frequency. During this process, the gear pair exhibits a smaller backlash on the rear tooth surface; as a result, hydraulic sealing is provided not only by the front tooth surface of the driven gear but also by its rear tooth surface. In this way, liquid flow is discharged alternately from the front and rear tooth surfaces. Furthermore, by adjusting the shape of the metering orifice, the hydraulic action line can be expanded to half that of a standard hydraulic pump. Structure of the Rexroth AZPS series gear pump: This external meshing gear pump is primarily composed of a pair of gears supported by bearing bushes, as well as a pump casing equipped with a front cover and a rear cover. The drive shaft extends outward from the front cover of the pump and is sealed by a shaft seal. These supporting forces on the bearings are absorbed by specialized bearing bushings ； Due to the sufficient elastic force of the sliding bearing, a surface contact is formed rather than a line contact. As a result, this also ensures excellent wear resistance of the pump—especially when operating at low speeds. These gears each have 12 teeth, which helps to minimize flow pulsation and noise in the gear pump. Internal sealing is achieved through compensating forces, which are proportional to the output pressure. By using this compensation method, optimal efficiency can be ensured. These bearings provide sealing for the ends of the gaps (that is, between the gear teeth that convey high-pressure oil). By applying working pressure to the rear part of the bearing bush, the sealing area between the gear teeth and the bearing can be controlled. These specialized seals form the boundary of this area. As for these radial gaps at the top of the gear teeth, sealing is achieved through the force that pushes the gear inward toward the pump casing. Precautions for Rexroth AZPS series gear pumps: Most failure cases of external meshing gear pumps are caused by contaminated hydraulic oil. Given that the warranty terms do not cover wear caused by contamination, we recommend using filtration methods that meet the ISO 4406 cleanliness levels of 20/18/15, in order to reduce contamination in terms of particle size and concentration to an acceptable level. We suggest that full-flow oil filters should always be used. According to the requirements of ISO 4406, the basic contamination level of hydraulic oil shall not exceed grades 20/18/15. Past experience shows that new oils often exceed this limit. In this case, an oil injection device equipped with a dedicated oil filter should be used. KraussMaffei AZPS series gear pump order codes: Order Code Page Number 0 517 215 001 190 517 215 301 190 517 225 001 220 517 225 002 230 517 225 301 220 517 225 302 230 517 315 001 190 517 315 301 190 517 325 001 220 517 325 002 230 517 325 301 220 517 325 302 230 517 415 001 190 517 415 301 190 517 425 001 220 517 425 002 230 517 425 003 240 517 425 301 220 517 425 302 230 517 515 001 190 517 515 002 190 517 515 302 190 517 515 303 190 517 515 304 200 517 515 306 200 517 525 001 220 517 525 002 220 517 525 003 230 517 525 004 230 517 525 301 220 517 525 302 220 517 525 303 230 517 525 304 230 517 525 306 250 517 565 011 260 517 615 001 190 517 615 002 190 517 615 003 210 517 615 301 190 517 615 303 190 517 615 303 200 517 625 001 220 517 625 002 220 517 625 003 230 517 625 004 230 517 625 301 220 517 625 302 220 517 625 303 230 517 625 304 230 517 665 007 270 517 665 304 260 517 665 305 260 517 715 001 190 517 715 002 190 517 715 003 190 517 715 301 190 517 715 302 190 517 715 303 190 517 725 001 220 517 725 002 220 517 725 003 220 517 725 004 230 517 725 005 230 517 725 006 230 517 725 008 250 517 725 301 220 517 725 302 220 517 725 303 220 517 725 304 230 517 725 305 230 517 725 306 23