As an industrial product, pump has gained more and more extensive application in transportation medium and power source, and more and more marine pumps, fire pumps, sewage settlement pumps, submersible pumps and the like are suitable for various special occasions. Some special pumps, such as fire pumps, the rapid development of increasingly high pressure, high flow direction, the original single pressure pump also appeared in the low pressure, high pressure or high pressure pump development trend, some of the original test The device has become incompatible, therefore, in order to pump product quality can be effectively controlled and improved, the design and construction of some new testing device is particularly necessary. A complete pump test device should include the following major components: power source; drive system; measurement and control system; auxiliary system; the design elements of each component. (1) power source: a. Clear the test object to determine the power source power unit design test device for different purposes, and some just for the unit's products for testing purposes, and some need for a variety of pumps (such as the test center), so the power Source of power should be based on the actual situation to determine. The calculation formula is as follows: P move = P pump / (η tooth × η twist × η from × η pump) = Q × P × H / (102 × η tooth × η twist × η from × η pump) Where: P move Required Power Source Output Power KW P Pump Pump Water Power KW η Gearbox Efficiency η Torsional Torque Meter Efficiency η η Clutch Efficiency% η Pump Efficiency% Q Pump Flow m3 / s H Pump's Head m V Water Kg / m3 We can take η pump as a reference, by calculating the relationship between P and P pump curve can be assumed in the calculation of η teeth, η twist and η were 0.95,0.98 and 0.98. When the P pump and the η pump are known, the output power can be determined from the power source required for the determination. b. Power source type: There are two common motor and diesel engine. The former generally not speed, suitable for general industrial pumps. Due to the difference in the rotational speeds of various industrial pumps, the parameters such as flow pressure and pressure of the pump generally need to go through the measurement values ​​under a specific rotational speed (motor speed) to the corresponding values ​​at the specified rotational speed of the pump, resulting in amplification of the measurement error. The former for speed, DC motor available SCR speed, AC motor speed control available, but the higher the cost. Of course, the use of motor has relatively low noise, no other pollution advantages; the latter applies to the fire pump, fire pump because there are changes in conditions require speed changes. Diesel engine speed more convenient. Regulate the throttle size and then with the gear box, you can get a larger speed range, and the cost is relatively low. The use of diesel engines there is noisy, flue gas emissions. What kind of power source should be selected depends on the design purpose of the test device and the unit's location, funding and existing relevant conditions. (2) transmission system: the use of diesel engine pump inspection device, there are transmission problems. Transmission system is mainly composed of clutch and gear box. The gearbox design, the main two issues should be considered: a. Speed ​​ratio to determine, for industrial pumps, the center of high 800mm below the pump, the speed is generally 1450r / min and 2900 ~ 2950r / min. Fire pump, its speed vary widely, usually 2000 ~ 4000r / min. Determination of gearbox ratio, it is necessary to consider to meet the test requirements of different speed pump, but also consider allowing the engine to work near the maximum torque point. According to the analysis, the following five speed ranges basically cover the test requirements of various fire pumps and industrial pumps: 1450 r / min, 2000 2400 r / min, 2900-2950 r / min, 3000-3600 r / min, 3600 ~ 4000 r / min. After selecting the right engine, depending on the engine speed and the above five speed ranges, the corresponding speed ratio can be determined. b. Output shaft steering, pump forward pump, reverse pump of the points, taking into account the versatility of the test device requires the output shaft of the gearbox in a variety of fixed speed range can be forward or reverse. Taking the system shown as an example, in order to realize the automated testing, the system should be composed of sensors, secondary gauges, computers, interface boards, servo mechanisms, collectors, combination screens and microcomputer software to realize the diesel engine starting in the control room, Start, emergency stop, diesel acceleration and deceleration and electric valve control; to achieve high temperature diesel engine, high oil temperature, low oil pressure and gearbox low oil pressure, high oil temperature alarm; automatic pump parameter acquisition and processing. Here are some specific issues described below: a. In addition to the pump operating parameters (speed, flow, pressure or lift, power) and housing temperature, the measurement should include the engine operating parameters (water temperature, oil temperature, oil pressure, engine speed), gearbox pressure, Oil temperature and auxiliary equipment related parameters (such as power temperature, fuel tank height, battery voltage, etc.), should also include the gear box gear and steering display. b. Measurement accuracy, and measurement of pump performance parameters corresponding to the sensor and the secondary instrument, the system's measurement accuracy should be consistent with GB3216 "centrifugal pump, mixed flow pump, axial flow pump and the vortex pump test method" provisions of the accuracy of various other measuring instruments Determined according to need. Should include: pump start, diesel engine start, emergency stop, speed increase or decrease; electric valve control (control flow); Pump condition switching and then the implementation of the test program control; Power between the cooling device automatic start control; Diesel water temperature, oil temperature, oil Pressure and gearbox oil temperature automatic monitoring and alarm. d. Matters needing attention: In order to improve the degree of automation of measurement, need to be equipped with electric valve to regulate the flow. Electric valve should ensure that the provisions of the pressure can be two-way operation (flow gradually increase or decrease), a jogging adjustment of 0.1 / s is appropriate; test site and control room should have pumps and engines, gearbox operating parameters Of the display, to ensure safe and reliable operation; when the pump does not check the case, the pressure gauge should be set before the valve, in case of vacuum instrument damage; strong, weak should be separated, so as not to interfere with each other, affecting the measurement accuracy; measurement Pump housing temperature, due to the rotating parts near, magnetic temperature probe should be used to avoid injury to test personnel; as much as possible the use of voltage regulator device to improve the accuracy of pressure measurement; secondary instrument output signal should be the same type, the same standard output Signal range, easy to connect with the collector, the computer interface: Automated measurement, telemetry data is transmitted through the secondary instrument into the data collector. Due to the negative voltage levitation of the second instrument transmission voltage, the multiplex voltage transmission signal and the data collector can not be directly connected. In this case, the isolation module method can be adopted to make the multi-channel signal reach the negative electrode after being transmitted by the isolation module, Send signal and data collector connection. Although this connection can achieve data transmission, but the secondary instrument transmit data superimposed ripple voltage can not be improved, resulting in large fluctuations in the value of the data show. In order to process the ripple in the process of communication between the telemetry data and the data collector, a level conversion method interface board can be designed to suppress the ripple in the level conversion process to ensure the data display value is stable. (4) Auxiliary system: Since the connection between the engine, the gear box and the torque meter are fixed, that is to say, when the position of the torque meter is fixed, the center height of the output end is fixed. In order to meet the high center of the pump test requirements, there is a need to install a pump lifting platform, the platform can be free to lift to a predetermined height, and then by pad and pump axial movement to adjust the pump input shaft and The degree of centering of the output shaft of the torque meter and the requirements of parallelism and clearance between connecting flanges. According to this installation feature of the test pump, it seems unnecessary to completely automate the height adjustment of the lifting platform. However, it is too complicated to adjust completely by padding and the like, which affects work efficiency. Therefore, the design of a semi-automatic pump lifting platform is appropriate. When the pump to be tested is an industrial pump, the motor should be used as the power source. When the pump to be tested is a fire pump, the diesel engine should be used as the power source. The problems in the measurement control, as described in the "Measurement and Control System" section, Design should cause enough attention; simple semi-automatic pump lifting platform is a suitable choice.