1、 1 Study on Computer Assistant Test System of ServoValve Test-bed Abstract： According to the need of the static and dynamic characteristics ofthe test on servo valve , firstly this article introduces the necessary part of the system-the pump station. Next, it designs the corresponding hydraulic and
2、computer-aided test system and given the composition of software and hardware of the test system and the design process of software.In the end,we apply the designed system to actual production to prove that it achieve the requirements of the test on servo valve. Key words： servo valve, test rig, CAT
3、, dynamic and static characteristics 1. Introduction Electro-hydraulic servo valve is the frequently-used control component in measurement and control system. Due to the wide use of electro-hydraulic servo system in metallurgy, engineering machinery, and chemical industry, a large number of servo va
4、lves are also be applied in these industries.Affect by the facters of environmental， abrasion,aging and so on,servo valve will malfunction inevitably and need repairs after using a certain time.After maintenance and repair,we must detect the servo valve through some certain testing methods of dynami
5、c and static to decide whether its various properties meet the stipulated requirements or not. Thus,large enterprises establish independent servo valve test-bed according to the own needs.What is described below is a servo valve test-bed developed jointly by our unit and a university and the test-be
6、d is based on computer-aided testing. 2 2.Hydraulic pump station Hydraulic pump station also known as the pump station is an independent hydraulic device. It offers oil according to the requirements gradually and controlls the direction, pressure and flow rate of hydraulic oil, applied to the mainfr
7、ame and hydraulic devices separability of hydraulic machinery. After the purchase users just connect hydraulic station and host of implementing agencies (motor oil or fuel tanks) with tubing, and hydraulic machinery can be realize these movements and the work cycle. Hydraulic pump station consists o
8、f pump device, block or valve, tanks, a combination of electrical boxes.The function of each components are as follows: (1)Pump device is equipped with motors and pumps, is the source of power of the hydraulic station. It changes mechanical energy into hydraulic oil pressure energy. (2)Integration b
9、lock is assembled by hydraulic valve and channel body. It can adjust the direction, pressure and flow of the hydraulic oil. (3)Valve portfolio plate valve is installed in the board and channels connect with each other after the board witch is the same as integration valve. (4)Tank plate is a welding
10、 semi-closed container, and also located with oil filtering network and air filters used for oil, oil filters and cooling. (5)Electrical boxes have two patterns. One designs external fuse terminal plate； The other installs a full range of electrical control. Hydraulic station principle: motor driven
11、 pump rotation, and pump absorbs 3 oil from the oil tank and changes mechanical energy into hydraulic pressure energy of the station. Hydraulic oil through manifold (or valve combinations) realizes the adjusting of direction, pressure, flow .Then through external pipe to the cylinder hydraulic machi
12、nery or motor, so as to realize the changing of the direction , the size of the force and the velocity, to promote the machinery working of all kinds. 3. Hydraulic testing system and testing methods Test-bed can complete the test on static and dynamic characteristics of servo valve.Static characteri
13、stics of the test includes characteristics of unloaded flow, characteristics of pressure-gain, characteristics of flow-pressure and characteristics of leakage； dynamic characteristics are mainly the test on frequency characteristics of servo valve. The above testing results of characteristics need to be drawn out in the way of graph. Figure 1 is a schematic diagram of hydraulic test system.
