The Most Optimization Gap Of The External Gear Pumps And The Research Of Vibration And Noise

The gear pump is an essential component in hydraulic system . This type of pump featuring the ease in realizing multi-unit design , high resistance to contamination ,workability under adverse conditions as well as its well-known compact construction ,light weight and low cost has become one of the most reliable and most popular hydraulic power sources .Since the use of hydraulic pressure technique ,high pressure research of gear pump has never interrupted .Yet with the pressure ascend ,the effectiveness of gear pump cuts down ,inner leakage adds ,make drive power loss .Since sixty percent of ordinary hydraulic pressure system input energy has been transformed to the heat energy and used up .But the power without work not merely creates energy resources waste ,but also transform to amount of heat ,and causes the oil temperature generate heat .Moreover arouse greater vibration and noise .It makes grave effect to gear pump work stability and service life .Therefore contemporary hydraulic pressure system design ,the total effectiveness of raise ,cut down the energy consumption was thought of as the significant indicator of quality .The hydraulic pump as the energy transformation unit ,has great effect to total efficiency of hydraulic pressure system .But the effectiveness is decided chiefly by the element physical design .But the gear pump effectiveness consists of volume efficiency and mechanical efficiency mainly .The volume efficiency is against three direct ratios in the gap ,and the mechanical efficiency succeeds the inverse proportion against the gap .So there is indispensability to carry on the parameter optimization .At the same time ,the external gear pump noise is comparatively greater .As main noise source of hydraulic pressure system ,there is about seventy percent of vibration and noise that comes from gear pumps .But vibration and noise have become the main obstruction to high pressure and high rotation .Hence the analysis of the noise ,influential factors and method of control is necessary.In order to raise gear pumps' effectiveness, we should analysis energy loss .The gear pump energy loss chiefly consists of the volumetric loss and mechanical loss .The volumetric loss acts as leakage . Leakage is divided into inner leakage and outward leakage .The outward leakage chiefly happen at the junction surface between the before and back lid .It is aroused by two seals badly airtight .The outward leakage should be averted, or decrease up to the lease degree .Inner leakage is mainly through the gap .The main method of inner leakage is :gear end face gap leakage ;gear radial gap leakage ;tooth contact part leakage ;reliance loss when liquid compressed .The main embodiment of mechanical loss is friction loss .Mainly including :the viscosity friction loss of tooth peak with liquid ;viscosity friction loss of gear end face with liquid ;the friction loss of shaft and bearing ;the friction loss of gear coupling;,the friction loss that shaft and shaft seal .To external gear pumps of CBZb2 set , in total leakage, is about 48%-60% , is about 37%-49%, is about 2%-3%.Comparing with , ,the energy loss at , , is little ,hence we merely consider the loss ,that have something to do with the gap . The volume efficiency is against three direct ratios in the gap , and the mechanical efficiency succeeds the inverse proportion against the gap .In order to make drive power minimal ,we should control the gap .But the total loss is the sum of the volumetric loss and that of viscosity friction .So it must have the optimum gap of two that make energy loss minimal .For this reason ,we put up the energy loss equation of axial gap and radial gap:(â… )Energy loss in end face gap :It consists of the end face leakage loss and the viscosity friction loss. = (â…¡)Energy loss in radial gap :It consists of the radial leakage loss and the tooth peak viscosity friction. =In order to obtain the most optimization gap , we suppose, ,thenThe most optim...