What are the structural and operational characteristics of Rexroth gear pumps?

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As we all know, Rexroth gear pumps have their own structural and operational characteristics. Different from gear pumps of other brands, what are the structural and operational characteristics of Rexroth gear pumps? Including some disadvantages? Structural features: (1) Simple structure, low cost ； (2) Low operational requirements, wide range of applications ； (3) The end cover and the grooves between the various teeth of the gears form numerous fixed sealing chambers, allowing it to be used only as a positive-displacement pump. The gears utilize a new technology at the international advanced level of the 1990s – the double-circular-arc sine curve tooth profile. Compared with involute gears, its most prominent advantage is that there is no relative sliding of the tooth profiles during gear meshing; as a result, the tooth surfaces do not wear out, operation is stable, there is no liquid trapping, noise levels are low, service life is long, and efficiency is high. By breaking free from the constraints of traditional design, this pump has opened up a new realm for gear pumps in terms of design, production, and use. The pump is equipped with a differential pressure safety valve for overload protection, the full return pressure of which is 1.5 times the pump’s rated discharge pressure. It can also be adjusted separately according to actual needs within the allowable discharge pressure range. However, this safety valve cannot be used as a pressure reducing valve for long-term operation; it can be installed separately on the pipeline when needed. The shaft end sealing of this pump is available in two forms: mechanical sealing and packing sealing, with the choice depending on the specific application conditions and the user’s requirements. Classification of pumps: In terms of their core component, the gear, they are mainly divided into external helical gear pumps and circular arc gear pumps. Public-normal gear pumps are more durable when transporting media containing impurities compared to arc gear pumps; arc gear pumps, due to their unique structure, produce less noise when handling clean media and have a longer service life. Each type has its own advantages. Working characteristics: Advantages: simple and compact structure, small size, light weight, good manufacturability, low cost, strong self-priming ability, insensitivity to oil contamination, wide speed range, capability to handle shock loads, easy maintenance, and reliable performance. Disadvantages: unbalanced radial force, large flow pulsations, high noise level, low efficiency, poor interchangeability of components, difficulty in repair after wear, and unsuitability for use as a variable pump.