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Delivery of perishable freights in proper quality essentially depends on the correct choice of a special vehicle and the correct calculation of the delivery time. According to the requirements of the Rules for the transportation of perishable freights by rail, all special vehicles by January 1, 2022 must obtain certificates of compliance with the standards established by the Agreement on the International Transportation of Perishable Foodstuffs and on special vehicles intended for these transports. This requirement applies to special vehicles used both in international traffic and for transport of perishable freights within the country. The article presents a brief classification of special vehicles used for the transportation of perishable freights. Formulas are given that allow calculating duration of transportation of such freights and average temperature of the outside air along the entire route. Procedure for choosing a special vehicle for the already known duration of freight transportation has been developed. It is concluded that the procedure proposed by the authors allows choosing the optimal special vehicle for the transportation of perishable freights. Using this sequence of calculations makes it possible to take into account the maximum number of external factors that affect the duration of transportation.

Satisfying the needs of the population in the delivery of perishable freight of good quality largely depends on the stable operation of specialized vehicles and the accuracy of calculating the deadline for transporting freight to the consumer. The main value used to calculate the deadline for the transportation of perishable freight by rail is the heat transfer coefficient of the body of an insulated car or container. The accuracy of estimating this value is especially important when using isothermal cars or containers that are not equipped with cooling or heating systems as specialized vehicles. In this paper authors assess the influence of some external factors on the value of the heat transfer coefficient of the body of an isothermal vehicle. The change in the heat transfer coefficient due to the influence of the speed of the isothermal vehicle and insolation is taken into account. The heat transfer coefficients from the internal and external building envelopes to the ambient air for the standing car and during its movement are determined to assess the change in the heat transfer coefficient from the criterion dependencies. Taking into account real external factors, in particular outdoor temperature, humidity, train speed, significantly affects the heat transfer coefficient of the body of an isothermal vehicle, the value was determined in stationary conditions of the workshop and underlying the calculation of the maximum permissible terms for the transportation of perishable freights. This value is excellent from the actual value. As a result of the calculations, a discrepancy of the value of the deadline for the transportation of perishable freights in comparison with the current method is 3–10 %.Changes to the existing methodology will reduce the risk of delivery of perishable freight of inadequate quality due to incorrectly calculated deadlines for transportation.

The main parameter determined in heat engineering tests of heat insulated cars superstructures or the locomotive operator’s cabs is the heat transfer coeffi cient К. The study introduces automated analysis technology for the heat transfer coeffi cient К of enclosure structures of the heat insulated transport means using a remote server. The underlying method provides coeffi cient K of the heat insulated transport means without additional work and time loss for complicated calculations. Personnel of test laboratories involved in heat engineering tests of vehicles possess tools for remotely calculating К, from any point in the world with internet access. To obtain К three controlled parameters measured during the heat engineering tests for 5.5 h including: the difference of the inside and outside temperature of the test object superstructure, total power of the electric heaters and geometric area of the heat transfer surface are sent to the server, after which the user promptly receives the calculated К. The economic effect of introducing the proposed technology for vehicle manufacture is the absence of required tests conducted at the test center; for an operating company — a signifi cant reduction of the idle time of the vehicle at the test center directly affects the loss of profi t. The proposed technology expands the area of operation of the test centers, while calculated К values are offi cially input into the data sheet of the vehicle.