1、液压管路冲洗程序Hydraulic pipes flushing procedure1. 目的/Purpose为了保证公司产品的液压系统正常工作，在系统投入使用之前,对系统进行全面、细致的油冲洗，以保证液压系统清洁度-清除系统制作、安装过程中潜伏在系统内部的污染。In order to the hydraulic system is running smoothly, we need flush the inside of hydraulic pipes and to clean the dirty.2. 冲洗的理论依据/ The theories of flushing2.1. 层流和紊流概
2、念/ Laminar flow and Turbulent flow层流是各流体微团彼此平行地分层流动，互不干扰与混杂。此时，液体流速较低，粘性力起主导作用；Laminar flow: the fluid of stratified flow in parallel to each other, each other without mixed. At this point, the liquid flow rate is low, viscous force plays a leading role.紊流是各流体微团间强烈地混合与掺杂、不仅有沿着主流方向的运动，而且还有垂直于主流方向的运动。
3、此时，液体流速较高，惯性力起主导作用。Turbulent flow is the fluid between strongly mixed micelle and doping, not only the mainstream direction of movement, but also in the direction perpendicular to the mainstream. At this point, the fluid velocity is higher; the inertial force plays a leading role.2.2. 雷诺数概念/Reynolds
4、 number雷诺数（Reynolds number）一种可用来表征流体流动情况的无量纲数，以Re表示，Re=vd/，其中 v、 分别为流体的流速、密度与黏性系数，d 为一特征长度。它是表征流体流动特性的一个重要参数。1Re is a dimensionless number of the fluid flow situation. Re=vd/; v is fluid speed, is fluid density, is coefficient of viscosity, d is length.流体流动是层流还是紊流由临界雷诺数 Rea判断。当流体流动的雷诺数 Re小于临界雷诺数 Rea
5、时，液流为层流；反之，液流为紊流。The fluid is laminar flow or turbulent flow, it is judging by Re. when Re is less than Rea (Critical Re), the fluid is laminar flow, otherwise, it is turbulent flow.一般管道雷诺数 Re4000 为紊流状态，Re=23004000为过渡状态。When Re is less than 2300, the fluid is laminar flow; when Re is more than 4000,
6、 the fluid is turbulent flow. From 2300 to 4000, it is transition stage. 2.3. 冲洗设备的选择要求/Requirement of flushing tools冲洗设备主要参数的合理选择对冲洗效果致关重要，其选择必须考虑以下两点：It is important for flushing that the data of flushing machine is defining; we need take care of below two points: 2.3.1 冲洗设备的流速、压力和温度/Flow rate, pr
7、essure and temperature of flushing machine 流速/Flow rate在任何冲洗回路中流速不应小于 23m/s，这可防止颗粒残留在管道内部。For each rout of flushing, the flow rate is more than 23m/s. it can clean the pipe inside. 温度/Temperature2冲洗回路最冷的部位温度应高于 50，这可通过提供 60的冲洗油达到，冲洗介质的温度对冲洗效果影响较大，通常冲洗温度控制在 50-6O，但不得超过65以上。The temperature is more tha
8、n 50 where is coldest area of pipe inside, the temperature can be keep by 60 hydraulic oil. The temperature of hydraulic oil is 506O, but it is less than 65. 压力/Pressure清洗回路的压力应大于 3bar。 为保证所有区域都得到有效的清洗，液压元件应处于全开状态。冲洗时要时刻注意滤油器进口压力与出口压力之差，当压差大于0.35Mp时就要更换滤芯。The pressure of flushing route should be big
9、ger than 3bar. In order to get the good result of flushing, all hydraulic components need be open. Before the filter, the pressure is bigger than 0.35Mp, please change the filter.2.3.2 过滤系统应有足够的容量和较高的性能，以便能在一个合理的时间内滤去固体颗粒和水分，并达到清洁度要求。过滤器(滤芯)的过滤比 x应大于100，本液压系统中原有的过滤器不要用来做冲洗过滤器。The filter should be bi
10、g, so that have enough time to filter the water and small dirty. The filtration ratio should be bigger than 100.3. 系统冲洗准备/Prepare for flushing3.1 管道机械清洗/Machine cleaning钢管的切割和弯曲，都可能在钢管中产生较大的颗粒。在热油清洗前，需要用工业压缩空气推动致密的泡沫子弹清除这些残留的颗粒。We use the soft material to clean the pipe inside, because when we cut a
11、nd bend the pipe, the dig filings is exist in pipe.3.2 回路中的重要元件/Important hydraulic components3 易被高流速、湿气、颗粒损坏的元件须采取短接；/Easily damaged by high velocity, moisture and particle components, should be short out. 流量调节元件会增加系统压力下降，应在冲洗回路短接；/Flow regulation components should be short out. 阀块、泵站、马达、油箱、组合件应按照特
12、定的程序进行冲洗。/Block, hydraulic unit, motor, tank and other assembling units should be flushing by special procedure.4. 热油冲洗/Hot oil flushing4.1 冲洗介质/Flushing medium冲洗介质必须与系统正常工作时的介质有很好的相容性，同时应给出在不同温度下的粘度。在实际操作时，通常选用工作介质作为冲洗介质。The flushing medium should be same with working medium.4.2 雷诺数的确定/Defining the
13、 Reynolds number对于表面粗糙的管道要求冲洗时的雷诺数根据公式计算，但至少应为 4000。对于表面光滑的管道，雷诺数为 20002300之间。For roughing surface of inner pipe, we need calculate the Re according to below formula, but the Re is 4000 at least. For smooth pipe, Re is 20002300.Re=d/ (黏性系数 =, 为流体运动粘度)，固 Re 也可以下公式计算：Re=d/。4.3 泵站和温度调节系统/Hydraulic unit
14、 and temperature adjusting system泵站应能提供足够的流量、流速、粘度和压力以清洗系统。根据雷诺数和管子内径确定满足排量的泵。泵站必须具有冷却系统。The hydraulic unit should be preparing the enough flow, flow rate, viscosity and pressure. Define the hydraulic pump according to Re and 4inner diameter of pipe. The hydraulic unit need include the cooling syste
15、m.4.4 管路连接/Flushing route根据管道尺寸规格，相近的规格尺寸连成一个回路。最好的是进油口在上，回游口在下，以便清洗完毕，更多的油能够流回油箱。According to the size of pipe, we can connect the similar size of pipe to one line. The entry port is in upper side and out port is in lower side so that the more oil can return the tank by gravity. 4.5 冲洗过程的温度和压力的检测位置
16、/Temperature and pressure check温度检测点/Temperature check position：A.初始油温测量油箱出口的位置，此处温度一般 60；The initial oil temperature B.回油路温度测量过滤器位置的温度，此处温度要大于 50。压力检测点 Pressure check position：A.第一个分流阀块位置检测油路压力；B.过滤器位置检测是否要更换滤芯。5. 冲洗过程中，系统清洁度的检测5.1 系统正常工作时的清洁度(NAS 或 ISO 4406)：根据设备制造商的要求确定。如设备制造商无明确要求，则建议为不低于 ISO4406 17/14或 NAS 8 级。5.2 系统冲洗的目标清洁度：比正常工作时低两个数量级。如正常工作时为NAS 8 级，则冲洗的目标清洁度应为 NAS 6 级。5.3 清洁度的检测：可在化验室进行，也可采用便携式清洁度检测仪现场检测。5PALL便携式污染度测试仪。5.4 清洁度检测周期：根据现场情况具体制定。5.5 取样：最好在回油总管回油箱处取样(需在回油总管上安装取样阀)。5.6 取样容器：清洁的取样瓶。
