Highlights of Urban Rail Transport Coatings after Motor Vehicle Accidents

With the Beijing-Shanghai high-speed rail's “colony nest” incident, a series of safety issues that have been exposed by Shanghai subway screen doors during repeated “self-detonation” incidents, especially the investigation of the Wenzhou train accidents, have also sparked public concern about motor vehicles, high-speed rail, and urban rail transit. Questioning and concern about safety. Taking rail transit as an example, China's urban rail transit has entered a period of gold development, and the scale of urban rail transit investment is large. Therefore, there are strict approval procedures for examination and approval. At present, the average construction cost per km of urban rail transit in China reaches 500 million yuan*** . As of the end of 2010, China has 12 cities including Beijing, Shanghai and Guangzhou. It has completed and opened an urban rail transit line and has operated 1,395 kilometers. In addition to coating materials for subway cars, investment in supporting facilities such as platforms and tunnels will generate huge market demand.

Highlights of Urban Rail Transport Coatings After an EMU Accident So, generally speaking, what performance requirements are needed for coatings used in urban rail transit to meet the need for safety?

Enough security to deal with accidents such as fire. Due to the continuous operation of vehicles in the rails, large passenger flow, and passenger flow enclosed in a narrow space for a certain period of time, the urban metro has many characteristics such as a large number of people per unit area. Once a fire accident occurs, it can easily result in group casualties and serious economic problems. Loss and bad social impact. In order to avoid or reduce the occurrence of such disasters, extremely high requirements have been put forward for the subway fire safety system. Subway stations must have good hardware facilities, such as a full range of monitoring systems and smoke alarm facilities. The non-metal fittings and decorative materials in subway stations and locomotives must achieve Class A fire rating. According to the provisions of GB50222-1995, the fire protection grade of decorative materials for large-scale public buildings must reach class A.

In addition, in the event of a fire at a subway station or vehicle, if the surface coating or other decorative materials fail to meet the AQ1 fire rating required by the national standard, the toxic and harmful gases generated by the burning of decorative materials in the event of a fire will be extremely high. Reduce the time for passengers to escape and cause personal injury.

Has good material weatherability. The subway station is a place where there is a dense flow of people. Pedestrians and luggage are inevitably scratched and bumped with the decorative sheet. Therefore, the standing material for the subway must not only have good scratch resistance but also have good stain resistance. , not easy to paste and graffiti. Even if there is slight pollution, it must be easy to clean in order to keep the station tidy.

For the safety performance of architectural coatings, the industry has always emphasized environmental protection, especially the emission of harmful substances such as VOCs and formaldehyde. For rail vehicle interior coatings, it is necessary to ensure the air cleanliness and personnel safety in a space-limited station, in particular that the number of people in a certain space is much higher than that of the building body, and it is a relatively confined space for harmful substances. Emission or radiation release requirements will be more stringent.

In addition, it needs to be both economical and aesthetic. In tunnels and other environments where subways pass through, it is generally necessary to face environments with relatively high humidity and relatively high carbon dioxide content. This requires coatings to have a long life cycle and reduce maintenance costs. The tunnel is very humid, paint is easy to mold off, and the subway coating also requires no reflection, searchlights shine on the wall to absorb light, so the requirements of the subway coating than ordinary wall paint requirements are much higher. Previously, it was reported that a Changsha citizen specifically found a new material research institute in Shanghai and tried to add a preservative and elastic emulsion to ordinary subway paint and developed a new type of subway paint. According to the report, the coating used in the subway tunnel is very viscous and can be sprayed directly on the tunnel wall. It will not be moldy and fall off when it is rainy or covered with water. For the exterior coating of the subway, it is required to have a variety of colors, elegant texture, soft gloss and other decorative. After all, as a kind of public transportation, its appearance must conform to modern design concepts and people's aesthetics.

The environmental protection of traffic coatings for aviation, aerospace, automobiles, ships, and rail transit has become the current direction of development, and the coatings and painting technologies for traffic use are also the most technically demanding types in industrial coatings. Due to the weak R&D and production capabilities of China's coatings and coating technologies, high-end traffic coatings have been monopolized by foreign companies. For coatings used in China's high-speed rail vehicles, including motor vehicles, CRH1's main paint supplier is Akzo Nobel, CRH2 uses Dainippon ink, CRH3 uses DuPont paint, CRH5 uses Akzo Nobel paint and a Paints from France. As an important part of traffic coatings, with the use of domestically-made locomotives, the development of urban rail transit coatings is expected to keep pace with the times and move into “domestic” paint. However, from the current situation, we still need to give A little time and confidence.