| 摘要 |
<p>The invention relates to a process and installation for thermally insulating the railway tank wagons meant for the transport of liquids, mineral water, aqueous saline, acid or basic solutions of low or medium concentration (maximum 50% concentration), of aliphatic hydrocarbons, of oil products (petroleum, fuels, benzines, diesel fuel) and of the mineral oils. According to the invention, the process consists in previously cleaning by sand blasting the metal surface of a tank wagon at a temperature of minimum 15 C and maximum 30 C, preferably 20 - 25 C, in spraying a mixture comprising two highly reactive components, a polyol component (A) and an isocyanic component (B), in a 1 : 1 flow rate ratio, at a temprature of 20... 40 C, preferably 25 - 30 C, the spraying of the reactive mixture, still in liquid phase, being performed by means of the compressed air, at a pressure of 4 - 10 bar, preferably 5 - 7 bar, with a stationary foaming equipment (6), in whose head there is made the mixture of the two components, the tank performing, during the spraying operation, a rotation motion with a peripheral speed of 5 - 90 m/min, preferably 10 - 50 m/min and a translation movement with a speed of 5 - 25 mm/sec, preferably 8 - 20 mm/sec, followed by the application of 3 - 5 successive layers of rigid polyurethane foam, and finishing the surface of the obtained insulation layer, by means of a rotary abrasive device, and coating the finished surface with a polyurethane, epoxy or polyester resin containing an UV stabilizer for the protection against the photochemical degradation because of the ultraviolet radiations.</p> |
