Design Of Measure And Display System For Rail Tank Car

Following the development of society, rail tank car is more and more widely used in chemical industry. Chemical medium is usually explosive, flammable, corrosive and poisonous. Once they are leaking without notice, there will be great disaster. In present, since there is no automatic monitoring system on rail tank car, it is hard to discover the leak even it happens. It is difficult to estimate the loss results from the explosive, flammable, poisonous and corrosive medium leaked.Combining the techniques of reed switch magnetic gauge, integrated temperature transmitter, PIC SCM, LED digital display and flameproof, the author designs and realizes a system which can measure & show the liquid level, temperature, pressure, volume, load and transfer the data meteraged. It is an integrated part that consists of solid body (reed switch magnetic gauge, integrated temperature transmitter, piezovesistive transmitter), PIC SCM, data processing system and digital LED display. The data transferred by transmitters is processed by PIC SCM and then send to digital LED display for escort to observe and check the medium in the tank.When car owner needs to check the current preferences of the medium in the tank, first the power supply in escort room should be turned on that leads to operation of each transmitter which sends signals of liquid level, temperature and pressure into devices housing. Data received will be sent to CPU after magnifying, and A/D switching. Then current measured values are calculated in accordance with zero point & scale set in the devices and sent to decoder which turns on numeral tubes through driving circuit. For example, ifwe need to find out liquid load in the tank, the "liquid/load (or volume)" button should be pressed. Then CPU receives transforming command, inquiring about liquid level/ volume and density table, sending the load value coming from multiplying volume 8b density to decoder which switch the numbers in liquid level display window into load value through driving circuit. We can also turn on power supply on manhole lid and check the field display on device.The gauge and display system can provide conditions in the tank for escorts at any time, which helps prevent accident and lessen harms from leaking. The system permits us to find out problem quickly, to prevent them in time, to solve them as soon as possible. Owing to the system, operation accident of rail car decreases considerably and safety 8b punctuality can be ensured in rail tank car transportation. The system can satisfy real time monitoring single car in operation as well as car unit. The working condition of medium in the tank can also be monitored during charging.