Application of Metal Surface Shot Blasting Technology in Inspection and Repair of Railway Vehicle Bogies

Through the analysis of the mechanism of the shot blasting technology on the metal surface, it has been flexibly applied in the technical demonstration of the surface cleaning in the inspection and repair of railway vehicle bogies, and it has achieved good results. Especially in the comparison of several surface cleaning solutions for vehicle bogies, the shot blasting technology is selected as the best solution, which provides an important reference for the selection and sizing of railway vehicle maintenance technical equipment.

The vehicle bogie is an important part of the vehicle. The cleaning of the bogie surface is an important part of the decomposition and maintenance of the vehicle. The quality of the metal shot blasting technology directly affects the quality of the subsequent inspection and maintenance procedures. In recent years, the surface cleaning technology of vehicle bogies has been continuously adjusted and improved, but it has always failed to achieve the desired results. Therefore, we are required to optimize the best solution as soon as possible to solve the problem of cleaning the surface of the vehicle bogie.

The current status and problems of bogie surface cleaning

The vehicle bogie is the support and running part of the vehicle, and the metal surface shot blasting technology and the surface blasting machine play a vital role in the safety of the vehicle. Therefore, the bogie should be derusted, descaled, and paint removed during the decomposition and maintenance of the vehicle to facilitate the appearance quality inspection and flaw detection of the bogie.

Over the years, the technology for cleaning the surface of vehicle bogies has been continuously improved in an effort to improve the quality of the surface cleaning of the bogies, facilitate operation, and reduce pollution. These techniques are nothing more than chemical methods, thermal methods, mechanical methods and different combinations of these three methods. The initial stage is pure boiling and washing, that is, a combination of chemical and thermal methods. The bogie is placed in a certain concentration of NaOH solution to cause alkali to chemically react with the rust, dirt and paint on the bogie. After the alkali water is heated and boiled for a certain period time, the bogie is hung from the alkali water, and the bogie is washed with clean water to achieve the purpose of cleaning the surface of the bogie. After the boiling and washing method, it has been developed into a pass-through (reciprocating) or rotary washing, that is, a combined chemical, thermal and mechanical method. Pull the bogie into the washing equipment, spray the bogie with the certain temperature and concentration of NaOH solution under a certain pressure, so that the rust, dirt and paint on the bogie will react chemically under the action of alkali (The heated alkaline water accelerates the chemical reaction), and under the impact of the alkaline water under pressure, the separation of rust, scale and paint from the metal surface of the bogie is accelerated. After a certain period time, the bogie is pulled out of the washing equipment (or in the equipment with cleaning) for cleaning to achieve the purpose of cleaning the surface of the bogie. This technology is the development of the boiling and washing methods, and the effect is better. However, with the rapid development of new vehicle technologies, alkaline water is forbidden during surface cleaning with the increase of rubber parts on vehicle bogies, and high-pressure clean water jets are used instead. However, while solving a contradiction, it also brought another problem, that is, the quality of the surface cleaning of the bogie decreased. This high-pressure clean water washing technology tries to use mechanical principles to clean the surface of the bogie but ultimately failed to achieve the desired results. 

In the comparison of various technical solutions, the surface sand cleaning technology of metal castings has attracted our attention. This is the metal surface shot blasting cleaning technology. However, whether the shot blasting of metal surfaces can be effectively applied and achieve the desired results in the cleaning of vehicle bogie surfaces is the subject of our research.