C73 Reading the Railway Rules and Standards

At the meeting the next day, the Canada experts continued to talk about the key to railway technology: the allowed error in the railway engineering measurement project.

After a day of training, Zhao Cheng, Jianguo Su, and Jianjun Cheng sat together again and continued to read the knowledge they had learned today.

"Today's information is more important. Everyone, look, the main projects for railway engineering are the foundation, the bridge, the tunnel, housing and the line. The other parts, such as the connection network, the signal standard, the equipment, and so on, were all based on the circuit. In terms of precision, the precision requirement for the roadbed was the lowest, followed by the tunnel, and then the bridgehead and the building, with the highest precision requirement for the circuit; in terms of the number of measurements, the tunnel and the roadbed were the most numerous. The second requirement for the circuits is the building and the bridge configuration is the least. " Zhao Cheng pointed out what he was concerned about.

"If there is a measurement error, there will be areas that we need to pay attention to when we make trains, or rather, places that we need to pay extra attention to. It seems like the safety of the trains is not concentrated on the train itself. They are still at the foundation of the roads, bridges, and tunnels. " Zhao Cheng said in realization.

"Teacher Zhao is right. It's just the precision of the route and the bridge. However, judging from the frequency of the test, the road is more important to the location, and the route is also the most important location. Therefore, we should pay more attention to the basic infrastructure of the roadbed, as well as the important assistance of the route. But the route. . . How precise is it?" Su Jianguo did not understand.

"Coordination of the electricity grid. " Cheng Jianjun said without thinking.

"Skynet? What is this?" Su Jianguo asked curiously.

"Yeah. What is this?" Zhao Cheng was also puzzled.

"God, GPS coordinates and GPS satellites. . . Our China is developing our own satellite, and I have a classmate researching it. Electricity, GPS, GPS, GPS. . . High-voltage power grid, or special power grid, are power trains, city power supply, and network power generators. It was the Internet, in the near future. The Internet would become the living habits of people, and even the foundation of instant communication. The Heavenly Network can also help train locate the route. " Cheng Jianjun said.

"Ah, in the end, he graduated from Beijing Traffic University. His knowledge is different, I understand. " Su Jianguo nodded.

"So that's what it means. " Zhao Cheng understood as well.

"The circuit measurement is the most detailed of all the railway engineering. The location of the rail point is about 10mm along the route, which is still acceptable. The vertical line direction is at most 3mm, plus the construction error, it's already a lot. " Cheng Jianjun read the error and raised his head to look at Su Jianguo.

As the data needs to be rigorous, refer to Average error caused by the railway engineering measurement project. Author Zhang Yong.

"Other than the direction being correct, there is also a key error in the trajectory of the railway. However, how can we ensure that the direction is accurate?" Whether or not Cheng Jianjun was an engineer, what they needed to ask was the experienced Su Jianguo.

"Put two points at the fork, usually at the end of the fork and straight fork. It will be troublesome if there are more. It is best to control it at 1-2mm; at the curve of the line, The mileage control of each curve is very strict, but the vertical line direction can be appropriately relaxed; the adjacent point of the high distance is generally controlled within positive and negative 3mm. However, this was not something to be worried about. The eyes of experienced teachers in this field were as accurate as water calibrators. They usually liked to raise their heads in panic and then look for details in a more accurate manner. This way, they can basically control it up and down to 1-2mm. " Su Jianguo recounted his current method of operation.

"Is it accurate to be around 2-mm?" Cheng Jianjun asked.

"Currently, teacher and I are working with the engineers, the rest of the engineers don't know" Su Jianguo explained.

"I feel that perhaps we can transfer the information on the railway tracks from 1990 to 1997. If our error is at 2mm and we maintain a good traffic record and no accident record, perhaps we can make an experience plan, feedback upwards, and share the experience with our colleagues in other provinces?" Cheng Jianjun suggested.

"That's a good idea, I'll do it. " Cheng Zhao nodded. That's right, the Canada company gave them a lesson on the types and importance of the standard testing projects. They had to pay attention to the places they did well and sort out the areas that they did not do well.

"The 'Orbit Design Standard' today also mentioned the railway tracks and parts, the straight line had ballast tracks, the ballast tracks, the station tracks, the seamless lines, the seamless lines, and the auxiliary facilities as well as the regular materials. We have to investigate these things when we get back. Let's look at the matching guidelines for railway rail design and train design. " After all, Cheng Jianjun was a designer. When they heard the news, The first thing he thought of was to go back and compare the previous standards to make comparisons.

"Indeed, we lack the selection standards for the tracks. Increase the technical requirements for the tracks to be 60N and 75N, as well as the filtering of the iron grade standards. " Zhao Cheng was more familiar with the technical standards of Shanghai's railway department. He knew which parts were lacking.

"Teacher Zhao, all the guidelines of Shanghai's railway bureau are hidden in your head. But which part of it needs to be analyzed carefully when we go back? " Cheng Jianjun asked curiously.

[Technology needs, refer to the TB 10082-2017 Rail Design Standard published by the railway department, JJJG404-2015 Rail Racing Ruler Instrument]

"[The station line has the standard for ballast rail track design and parts of the hammer, pillow, and bed. There are also basic rules for seamless railway design. ]" Zhao Cheng thought for a moment and said.

"It seems that we have a lot of things to prepare. " Su Jianguo recalled the technical specifications as well. "It seems like there are also defects in the rail measuring tool. "

"Ah, yes, there are defects. " Zhao Cheng nodded.

"What do you mean?" Was Cheng Jianjun not an engineer for maintenance, or was he lacking in knowledge in this aspect?

"When determining the length of the workload pole, we will use a measure of uncertainty that is not greater than 0. 5mm to measure. But now it seems that it is not ideal. " Su Jianguo recounted his experience. "Using an uncertain measurement method that is not more than 0. 02mm to measure is more accurate. It is just that the cost and cost of this measuring device are there. There is still a need for further analysis and consideration. "

"If you want to do something, you must first use this measuring device. This measuring device is the key to the installation of the tracks, and it is the first requirement that Green Island Company has taught us. Looks like we have to think of a way carefully" Zhao Cheng also thought of a countermeasure.

"Also, the original ultra-high measuring ruler has a gap of 1505 mm between the two edges, and the super high measuring ruler has a high false value problem due to the vertical angle of the top of the measuring block. This problem is also very troublesome. " Cheng Jianjun thought of the problem he had encountered a while ago.

"This problem, recently my team and I have some experience with it. " Su Jianguo explained.

"Oh? What solutions do you have?" Zhao Cheng asked curiously.

"Rules on the level difference between each block, which is the parallel level of the workspace, allow a combination of no more than 3 pieces of the block; the last type of detector, the super high return value of a level 1 detector, does not exceed 0. 0001%. 06mm, the super return value deviation of the level 2 detector does not exceed 0. 0. 20mm. " Su Jianguo explained his solution.

"This solution. . . The requirements are a bit harsh. " Zhao Cheng said.