Rolling stock painting technology with two-component polyurethane materials “base + varnish” (including “metallic”)

JSC Wagon-Service uses the latest technologies in rolling stock painting; these technologies are fully certified in cooperation with OJSC "VNIIZHT” and successfully implemented in our operational activity.

Painting technologies that involve two-component polyurethane materials have a number of important advantages, compared to alkyd painting technologies which are still widely utilized on railroads. Polyurethane coatings provide the painted surface with the following:

• qualities that expand coating service life up to 6 years;
• modern look;
• qualities that reduce discoloration, burn-out and soiling effects during the service;
• qualities that allow local body repairs, followed by local-only painting of the damaged parts;
• qualities that allow to complete paint jobs 3 times quicker for 2 – 3 color schemes.

Two-component polyurethane coatings (including “metallic) make the surface even more resistant to the environment, thanks to light-reflecting particles.

The application technology for polyurethane coating seriously contributes to time and resources saving. It makes possible to apply a second layer after only 20 minutes. This polyurethane property is particularly convenient for multicolor carriage painting.

The workflow of polyurethane paint application, according to technology implemented by JSC Wagon-Service, involves the following operations:

1. Shot-blast treatment.
2. Surface grounding with chromateless epoxyetherial primer.
3. Sanding of the surfaces under repairs. Sanding of damaged parts after heat-mechanic correction.
4. Surface cleaning and degreasing.
5. Body grounding with chromateless epoxyetherial primer after body repairs. Grounding of the body sections that underwent heat-mechanic correction.
6. Sanding of the surfaces under repairs.
7. Surface cleaning and degreasing.
8. Filling application.
9. Surface polishing.
10. Surface cleaning and degreasing.
11. Surface grounding with chromateless epoxyetherial primer.
12. Surface grounding with polyurethane primer.
13. Application of the finishing enamel on the carriage roof.
14. Grounded surface treatment.
15. Surface cleaning and degreasing.
16. Grounding of the polished-to-the-metal parts with epoxyetherial primer.
17. Body painting with the base color (or multiple colors in sequence in case of multicolor paint job)
18. Varnish application.

After these operations the rolling stock surfaces coating thickness increases to 245 – 350 Mm, which significantly prolongs its service life.

Utilizing NitroThermoSpray^TM system

In rolling-stock painting JSC Wagon-Service utilizes the Italian technology patented by EUROSIDER – NitroThermoSprayTM. It is state-of-the-art equipment.

The system uses 99,5 % nitrogen heated gas mixture for spraying, instead of commonly used air. This principle significantly reduces paint viscosity and reduces the use of thinner by 50%. It results in reduced amount of layers of paint and varnish; the whole paint job takes less time (by 50%) and resources. Even so the system meets the strictest ecological requirements due to low emission of organic volatile matter. It also reduces the influence on personnel health and helps to prolong painting rooms service life.