Case Sharing-PMT bolsters China's burgeoning rail transit industry

Today, the global rail transit industry is booming through constant exploration of new technologies, new materials, new processes, and new equipment. Railway bogies are an essential part of the train. The bogies support the mass of the vehicle, use the wheels to guide it along the track and provide some degree of cushioning against the shocks transmitted from the track during motion, keeping the train stable and cozy.

Challenges

Railway bogies easily wear, deform and cause inner stresses due to the wear of components and external forces after the train runs a certain kilometer. In addition to shot blasting and flaw detection, a dimensional inspection on the bogies is necessary to check wear deformation and remove inner stresses.

Before the introduction of PMT ALPHA portable measuring arm, customers often used manual measuring tools, such as caliper, tape measure and inside micrometer. These traditional methods require very high demand for specialized skills and can not help customers see GD&T results more distinctly. Other disadvantages include higher workload, long time consumption, limited data collection and manual errors.

Therefore, the usage of ALPHA portable arm in railway bogies size measurement plays a vital role for the production, assembly, and maintenance of rail locomotives.

Background of the project

As of early 2023, China had 27 rail transit lines in operation in Beijing, with a total mileage of 807 kilometers, ranking first in the country and second in terms of mileage. The Beijing Metro Management Company was planning to extend metro lines and upgrade current lines to meet the growing market demand. In the meantime, there is an ever-increasing demand for train maintenance work due to a steady increase in the country’s vehicle ownership.

In this context, in order to ensure the safe performance of railway bogies, Hebei JingChe Rail Transit Vehicle Equipment Co., Ltd. actively engaged and pushed the collaboration between PMT and CRRC Corporation Limited on the real-time dimensional inspection of rail transit parts. Headquartered in Beijing, CRRC Corporation Limited (CRRC) is the world's largest supplier of rail transit equipment with the most complete product lines and leading technologies. This cooperation boosted Beijing’s rail transit and addressed the huge needs.

Solutions

Whether it is in a laboratory with constant temperature and pressure or in the on-site assembly under changing environmental conditions, the PMT measuring machine can provide flexible and multi-angle solutions for the visible parts of the train such as bogies. In this way, it efficiently avoids manual errors in large, greatly improves the accuracy of measurement, and is more in line with the needs of modern rail transit testing.

• Key points of the measurement:

1. Measure the parallelism, plane and surface of the four axle box parts of the bogie;
2. Measure the size of the axle box diagonal (mostly ≥ 4000mm);
3. Analyze data for compliance with technical requirements and instruct the assembly jobs;
4. Provide professional measurement report at any time.

• Advantages:

1. Measurement range/configuration: 4.0m/6-axis；
2. Operating temp range: 5 - 45℃；
3. Inspect whenever, wherever, without moving the bogie；
4. Archived measurements for data traceability and analysis.

By adhering to the principle of “Promoting original innovation, leading green and intelligent development, embracing an innovation-driven development model, and expanding international cooperation”, the rail transit industry is thriving in China. The comprehensive measurement solutions offered by PMT guarantee a smooth running of bogies, optimize the quality control system of locomotives, and are beneficial for high-efficient development of production capacity structure.