PROSOFT MVI56-BAS 可编程应用

检查针阀的设置和补偿调整（见第4章，补偿调整）。5.在工作温度下，检查机油是否清洁，油位是否正确。液压调速器的大多数故障源于脏油。砂砾和其他杂质可能会随油一起进入调速器，或者在油开始分解（氧化）或变得粘稠时形成。内部运动部件由装置内的油持续润滑。由于油中的砂砾和杂质，阀门、活塞和柱塞会粘在孔中，甚至“冻结”。如果是这种情况，可以通过用燃油或煤油冲洗装置来纠正不稳定的操作和不良响应（如果磨损不严重）。不建议使用商用溶剂，因为它们可能会损坏密封件或垫圈。如有可能，每年更换机油并冲洗调速器两次。要更换机油，请拆下放油塞并排出旧机油，向调速器加注燃油以冲洗调速器，在原动机低速运行的情况下，打开针阀使调速器循环两到三圈。

即使补偿可能已经在工厂或调速器测试设备上预先调整过。尽管调速器的运行可能令人满意，因为机组在无负载的情况下以恒定速度运行，但调速器仍可能无法根据其控制的负载和发动机进行正确调整。负载变化或速度设定值变化后，高过速和低欠速，或恢复速度缓慢，都是补偿调节和针阀设定值不正确的结果。定义使用以下页面上的故障排除图表（表5-2）来确定故障操作的可能原因并纠正这些故障。图表中使用的术语定义如下：Hunt速度的有节奏的变化，可能源于调速器或原动机。（有关故障排除信息，请参见表5-2第1A段。）寻道的频率通常小于50 Hz/min。喘振以周期性间隔发生的速度突然变化，也可能源于调速器或原动机。（故障排除信息见表5-2第1A段。）调速器输出轴和燃油连杆的抖动A高频振动。不要将其与调速器的正常控制动作混淆。抖动的频率超过50赫兹/分钟。初步检查调速器故障通常表现在原动机的速度变化中，但不一定是调速器引起的。当出现不适当的速度变化时，应执行以下步骤：1。检查负载，确保速度变化不是超出原动机容量的负载变化的结果。2.检查发动机工作情况，确保所有气缸都正常点火，喷油器处于良好的工作状态并正确校准。3.检查调速器与燃油齿条或阀门之间的联动装置。决不能有束缚或空转。

 There must be no binding or lost motion. 4. Check the setting of the needle valve and compensation adjustment (see Chapter 4, Compensation Adjustments). 5. Check that the oil is clean and oil level is correct at operating temperature. The source of most troubles in any hydraulic governor stems from dirty oil. Grit and other impurities can be introduced into the governor with the oil, or form when the oil begins to break down (oxidize) or becomes sludgy. The internal moving parts are continually lubricated by the oil within the unit. Valves, pistons, and plungers will stick and even “freeze” in their bores due to grit and impurities In the oil. If this is the case, erratic operation and poor response can be corrected (if wear is not excessive) by flushing the unit with fuel oil or kerosene. The use of commercial solvents is not recommended as they may damage seals or gaskets. Change the oil and flush the governor twice a year if possible. To change oil, remove the drain plug and drain out the old oil, Flush the governor by filling it with fuel oil and, with the prime mover running at low speed, cycle the governor by opening the needle valve two or three turns.

 Jiggle A high frequency vibration of the governor output shaft and fuel linkage. Do not confuse this with the normal, controlling action of the governor. A jiggle has a frequency of more than 50 Hz/min. Preliminary Inspection Governor troubles are usually revealed in speed variations of the prime mover, but it does not necessarily follow that such variations are caused by the governor. When improper speed variations appear, the following procedure should be performed: 1. Check the load to be sure the speed changes are not the result of load changes beyond the capacity of the prime mover. 2. Check engine operation to be sure all cylinders are firing properly and that the fuel injectors are in good operating condition and properly calibrated. 3. Check the linkage between the governor and fuel racks or valve. 

 even though the compensation may have been previously adjusted at the factory or on governor test equipment. Although the governor may appear to be operating satisfactorily because the unit runs at constant speed without load, the governor still may not be correctly adjusted to the load and to the engine it Is to control. High overspeeds and low underspeeds, or slow return to speed after a load change or speed setting change are some of the results of an incorrect setting of the compensating adjustment and needle valve. Definitions Use the troubleshooting chart (Table 5-2) on the following pages to determine the probable causes of faulty operation and to correct these troubles.Terms used in the chart are defined as follows: Hunt A rhythmic variation of speed which can originate in the governor or in the prime mover. (See Table 5-2, Paragraph 1A, for troubleshooting information.) A hunt usually has a frequency of less than 50 Hz/min. Surge A sudden variation of speed occurring at periodic Intervals which can also originate in the governor or in the prime mover. (See Table 5-2, Paragraph 1A, for troubleshooting information.)