Step 1: Line and Vehicle Survey
After the grinding plan is determined, the engineering section provides the on-site investigators with relevant information on the line, rails and running vehicles. Based on this information, the investigators conduct a detailed investigation of the normal state sections and key disease sections of the rails, record the state of the rails, and collect their profile data. The investigation covers a wide range of topics, including various diseases, wear conditions, corrugation conditions and crack conditions of the rails. The vehicle profile collectors also investigate the main running vehicles on the line, collect the vehicle profile data of passenger and freight vehicles in the wear state, and provide a basis for the personalized rail grinding profile design.
Step 2: Grinding Target Profile Design
The personalized rail grinding profile design team deeply analyzes the problems and rail diseases found in the line investigation, and processes the collected vehicle profile data. Based on the wheel-rail creep minimization and wheel-rail coupling contact theory, they use relevant dynamic simulation software to establish a real-parameter vehicle-track coupling system dynamic model of the main running vehicles and line data of the current line. Complex grinding profile design calculations and verifications are carried out to finally obtain the personalized rail grinding profiles for different sections.
Step 3: Grinding Scheme Design
After the grinding profile design is completed, the scheme design team compares the design profile with the actual rail profile and formulates grinding schemes for different sections. The design process is based on the principle of minimizing the amount of grinding to ensure that the grinding vehicle can directly use the design scheme to grind the rail profile to the design requirements. For sections that require repair grinding, the design scheme gives priority to dealing with defects, while taking into account the profile requirements while solving the defects, so as to achieve the purpose of both solving the defects and optimizing the profile.
Steps 4 and 5: Technical Explanation, Grinding and Optimization
Before the grinding operation begins, the on-site service personnel conduct technical explanations with the engineering section and the large machine section, and discuss in detail the feasibility of the grinding scheme and the precautions in implementation. After the grinding operation begins, the on-site service personnel follow the vehicle to record the state of the rails before and after grinding and collect relevant profile data. Since the grinding capacity of different grinding vehicles and the actual state of the rails may differ, within 2 to 3 days after the start of the grinding operation, the technicians need to confirm and optimize the plan to ensure the grinding quality.
Steps 6 and 7: Result Acceptance and Follow-up Observation
After the grinding operation is completed, the grinding results are inspected to ensure that the rail state meets the expected requirements. The on-site service personnel organize the acceptance with the engineering section and the large machine section to strictly evaluate the grinding quality. During the acceptance process, the acceptance of the rail profile adopts the GQI index score management method, and a comprehensive inspection is carried out on other acceptance contents to ensure that the grinding results meet the expected requirements.
After the grinding and acceptance of each line is completed, observation points are set up in some important sections and regular measurement and tracking are conducted. In this way, the state changes and grinding effects of the rails are continuously observed, analyzed and summarized. Targeted guidance for line maintenance and the next stage of grinding work is also provided based on the observation results.
Frequently Asked Questions
What does the line survey collect? Rail diseases, wear, corrugation, cracks and the profile data of the running vehicles.
How is the target profile designed? By dynamic simulation of wheel-rail contact using the survey data to minimize creep and stress.
What is the principle of scheme design? Minimizing the grinding amount while solving defects and optimizing the profile.
How is the grinding result accepted? By the GQI index score method for profile and comprehensive inspection of other items.
Why is follow-up observation needed? To track the grinding effect and provide guidance for maintenance and future grinding.
