Study On Structure Of Heating System For Railway Viscous Oil Tank Car

In China, the important energy sources such as crude oils and heavy oils are mainly transported by viscous oil tank cars. As the transported medium has high freezing point and needs to be discharged under heating condition, therefore the heating systems are generally installed for this type of tank cars. The performance of the heating system on the viscous oil tank car, one of the main economic and technical specifications for the tank car, is related to the safe running, transporting efficiency and energy utilization.In this thesis, the study on the structure of heating system for viscous oil tank cars in China is undertaken, and the development history of the tank car heating systems in China and foreign countries are discussed. Through the analysis for the heating mechanism of the tank cat heating device, the main factors which affect the viscous oil discharging and thermal exchange are given, and the structure design methods for tank car heating system are suggested. The oil leaking problem happens on interior heating coil of G17B tank car in operation. Through survey, failure analysis of breaking parts, water discharging simulation test, and "ice-bulge" test etc, the main reason of leaking is found as: flange sealing failure of the heating coil;heating coil broken resulted from icing of the pipe;the "water hammer" phenomenon may appear in the heating coil. Taking the heating structure for 70t viscous oil tank car as a study platform, a new heating structure with row pipes which fits the viscous oil tank car is presented. On the basis of steam allocation calculation for heating pipes, the thermal efficiency comparison tests between 70t viscous oil tank car and G17B tank car are carried out, which including thermal field distribution of pipe structure, temperature increase rate, energy source utilization ratio, steam allocation and condensate water discharging, and so on. Through tests, the comprehensive performancesof row pipes structure are validated, and the problem on existing interior heating system is solved, which can provide the reference for heating system modification of G17B tank car.For the particularity of rail tank car heating system, we can not completely copy the theory and structure design of thermal exchanger of chemical industry. The heating system for rail tank car should be made safer, more reliable and more economical to provide a strong back-up for the development of rail tank car through continuous practice and exploration.