微灌直动式减压阀设计及其参数对预置压力影响研究

Design of Direct-acting Pressure Reducing Value and the Effects of the Parameters on Its Preset Pressure

微灌系统中,在各支管进口处安装减压阀,可以改善灌水均匀性,提高灌溉质量。设计了一种预置压力可调且能实现开关功能的灌溉用直动式减压阀,由阀体、运动组件、弹簧控制组件和开关组件4大部分组成。结果表明,阀芯直径对减压阀预置压力的影响较小,弹簧刚度、弹簧初始压缩长度、膜片受力面直径和阀芯到挡板下侧壁面初始间距等4个因素影响显著,与减压阀预置压力都有较为明显的线性关系,并建立了4个因素与预置压力之间的定量关系式,根据该关系式,并结合试验,定型开发了一种减压阀,该减压阀调压性能良好。

It would greatly improve irrigation uniformity and enhance irrigation quality by installing pressure reducing value at the inlet end of the manifold in the micro-irrigation system.A direct-acting pressure reducing value was designed,including value body,motion components,spring control components and switch components.The value had the function to adjust its preset pressure,also the function to open or close itself.Through theoretical analysis,the main factors affected the preset pressure were obtained：the spring stiffness（K）,the initial length of the compression spring（K）,the diameter of the value plug（d_1）,the diameter of the diaphragm＇s stress surface（d2）,the distance between the value plug and the lower wall surface of the apron（h）.A series of experiments were processed;the results showed that the value＇s preset pressure had a weak relationship with the factor d1 and had strong linear relationship with other four factors.In addition,the regression model described the quantitative relationship among the four factors and the value＇s preset pressure.Based on the relationship and experiments,a kind of presure reducing value was developed,which had good performance.