This summer, a large number of domestic and foreign tourists took EMUs to travel to the south of Caiyun. The number of passengers on the Yunnan Railway exceeded 23 million. Among them, many tourists took the China-Laos Railway EMUs to travel across the country. At peak times, the

This summer, a large number of domestic and foreign tourists traveled to Caiyunzhinan on EMUs. The number of passengers on the Yunnan Railway exceeded 23 million. Among them, many tourists traveled cross-border on the China-Laos Railway EMUs, with the number reaching more than 4,000 per day at peak times. Amid the lofty mountains of China and Laos, trains of CR200J power-intensive EMUs are speeding along, injecting a steady stream of vitality into the areas along the routes.

(Wang Chao led studio members to conduct on-site research, photographed by Chen Tunan)

The interweaving trains on the railway constitute "Mobile China". Behind the normal operation of the road network, there are silently dedicated railway craftsmen. Wang Chao, a vehicle electrician in the maintenance workshop of the Kunming depot of China Railway Kunming Bureau Group Co., Ltd., is one of them.

From overhauling bus electrical systems to repairing circuit motherboards, Wang Chao has been working on the front line for more than 20 years, constantly innovating methods and honing his skills. Wang Chao said: "I don't have any hobbies, I just like to repair trains. This work is meaningful and interesting to do!"

In the past five years (since April 2019 to date), Wang Chao has led his team to successfully repair the integrated boards of high-speed trains. There are 3,910 high-value accessories such as cards. He summarized and refined more than 30 difficult and troubleshooting methods such as "plc program database maintenance methods" and obtained 1 national invention patent and 12 national utility model patents. He won the "National May Day Labor Medal" Honor.

(Photo by Tang Chuanling as Wang Chao conducts board experiments)

Welding is reborn with unique ingenuity

"Wang Chao Skill Master Studio" is located in the Kunming depot on the outskirts of Kunming. Stepping into the studio, Wang Chao, the railway passenger car chip welder The "art master" in the field is concentrating in front of a power supply main control board under the car that is on the verge of being abandoned.

He held the welding gun steadily in his right hand and held the magnifying glass lightly in his left hand. As the soldering iron tip passed over the soldering feet, the soldering wire was like precise strokes, outlining precise patterns on the solder joints. The

cr200j power-concentrated EMU under-car power supply main control board carries more than 30 precision chips, among which the DSP chip is the core of the core, just like the central processing unit of a computer, commanding every pulse of the inverter. In this small space, Wang Chao used his craftsman's heart to challenge the almost impossible task - manual welding of DSP chips. This is not only a competition of technology, but also a test of patience and perseverance.

A chip smaller than a fingernail is densely covered with more than 200 solder pins. The distance between them is as thin as a hair. If you are not careful, all your previous efforts may be wasted. But Wang Chao, relying on micro-carving skills under a high-power magnifying glass, accurately "embroidered" each solder foot on the integrated circuit board, giving the circuit board a new lease of life and making the dream of independent maintenance a reality.

Looking back, Wang Chao’s technical journey was not a smooth one. Since he stepped into the Kunming depot in 2002, he has grown step by step from an apprentice who knew little about railway maintenance to the skills master he is today.

In the beginning, he followed his master to clean car lights and deal with daily faults every day, thinking that vehicle maintenance was just an accumulation of daily trivial matters.

One day, an insulation failure occurred in a car. It happened that the master was not on duty. Wang Chao was sweating profusely and could not solve the problem. When the master came back, he found the cause of the fault by looking at him three times, five and two. Wang Chao is deeply aware of the power of technology and his own shortcomings. From then on, he secretly made up his mind to develop excellent skills.

Before the end of 2012, Wang Chao worked in the vehicle and electrical group of the maintenance workshop, mainly responsible for the maintenance of electrical equipment of railway passenger cars. During this period, Wang Chao, who loves to ponder, can always quickly discover the fault of the under-car power host communication circuit of

, which is repaired by the technical research team, showing a skill level beyond ordinary people.

At the end of this year, he was transferred to the technical research team and began to learn the maintenance of the power supply host module. For countless days and nights, Wang Chao was immersed in the ocean of technology, asking his masters for advice and discussing with colleagues, and gradually mastered the skills of under-car power supply maintenance. Soon, the master's job was transferred. When faced with the important task of overhauling the power supply host module, he overcame one technical difficulty after another with an unyielding determination.

At that time, the relatively simple 8-pin chip welding technology was also a "stuck" problem in maintenance.With no experience to draw from, Wang Chao took the card board to the electronic repair market in Kunming and asked for help. He even asked mobile phone repairmen to help at his own expense, but he was rejected.

Wang Chao was not discouraged. He did not understand chip soldering, so he started learning from the most basic soldering principles. He collected scrap boards, looked up information, and purchased materials. He tried again and again, failed again and again, and stood up again and again. During this period, Wang Chao repeatedly tried to sharpen, flatten, and grind the welding head into a blade according to different welding conditions to practice his welding skills.

When Wang Chao successfully found the technique of grinding the welding head into a knife head, he discovered that there were similar welding heads on the Internet. "It seems like we have done nothing, but through repeated practice, we found the best solution for welding with different welding heads, materials, and temperatures." Wang Chao said.

After more than 1,120 days of trial and error and more than 600 failures, I finally gained the joy of success. He mastered the welding technology of chips from 8 to 200 pins and solved the technical problems of board repair. With the continuous improvement of board maintenance technology, the maintenance work that originally cost tens of thousands of yuan to be completed by outsourcing has become an independent maintenance project that costs hundreds or even dozens of yuan, saving a lot of maintenance costs and making it more popular in the industry. Set a benchmark for technological innovation.

At the end of 2015, the Yunnan Provincial Department of Human Resources and Social Security named the "Wang Chao Skill Master Studio" in Kunming Depot after him, which is a full recognition of his technical strength and social contribution.

Technological innovation, scaling new heights

On the eve of the opening of the Yunnan High-speed Railway in 2016, Wang Chao was given a special mission - to go to Wuhan and Fuzhou for further studies, to participate in high-speed rail train mechanic training, and to prepare skills for the opening and operation of the high-speed rail.

Wang Chao is full of passion and longing, ready to welcome a new chapter in his career. However, fate seemed to have played a joke on him. He was informed that he needed to continue to stay in his original position because no suitable candidate was found to replace him.

Faced with the sudden change, Wang Chao did not give in. Instead, he turned this regret into a deeper study and love for technology.

At that time, the dc600v conventional inverter for railway passenger cars was facing the challenge of upgrading. The test bench in the maintenance warehouse could not conduct on-site testing. The entire power box needed to be disassembled and transported to the test bench with a forklift for testing. Such a complicated process , only one vehicle can be inspected every day, but the inspection task is 4 vehicles, which cannot meet the growing inspection demand at all. I went to the

unit to find a manufacturer to help solve the problem. The other party suggested purchasing a new test car worth 1 million yuan. Faced with this problem, Wang Chao took the initiative to stand up. He knew that only technological innovation could break through the bottleneck. With the encouragement and support of the workshop director, he led the team to face the difficulties and began a long and arduous road to technical research.

The hard work paid off. After half a month of hard work day and night, Wang Chao and his team finally developed a test device capable of on-site bicycle testing. The maintenance efficiency increased to more than 5 vehicles per day. This innovation greatly improved It improves maintenance efficiency and saves enterprises a lot of costs.

When the news came back to the manufacturer, even the manufacturer’s after-sales staff couldn’t help but give a thumbs up, and specially sent personnel to Kunming to ask Wang Chao for advice. When Wang Chao told the other party's technician that he solved the problem using the mutual power supply principle of the inverter, the other party expressed his sincere admiration for the talent and perseverance of Wang Chao's team.

It has become Wang Chao’s work pursuit to develop the maintenance technology of “I have what others don’t have, and I have what others have”. Over the years, six thick work notebooks recorded his growth. His skills were not only recognized by his colleagues, but also won the honorary titles of Yunnan Provincial Technical Expert, All-Road Technical Expert, and National Technical Expert.

However, Wang Chao's footsteps did not stop because of this. He knows that the exploration of technology will never end. Subsequently, he led the team to develop a communication function test device for railway passenger car network control components, which is equivalent to building a network system for two carriages. The application of this maintenance method and technology effectively solved the problem of under-car power communication function testing and passenger car testing. Network accessories testing and power supply troubleshooting issues.

This innovative achievement is like giving a pair of wings to the field of railway maintenance, making maintenance work more efficient and precise. This saves millions of yuan in maintenance costs every year, and this research and development achievement has also won the national invention patent.

In the summer of 2017, Wang Chao, as the only youth representative, participated in the World Youth Skills Day event jointly organized by the Ministry of Human Resources and Social Security and Yunnan Province, showing his superb skills in the field of comprehensive maintenance of railway passenger cars to skilled talents and media from all walks of life. skill. At that moment, he became a "star" in the spotlight, but what made him even more proud was that he could use his own hands to contribute to the railway industry of the motherland.

Wang Chao said: In the journey of technology, there is no end but only a starting point; as long as you have dreams and have the courage to climb, you can continue to surpass yourself.

Challenging the limit, innovation leads

In 2021, when the China-Laos railway is about to be opened for operation, Wang Chao faced new fields and challenges without flinching. Instead, he resolutely devoted himself to it and worked silently for the smooth opening of the China-Laos railway. However, with the official operation of the train, a series of unknown challenges followed.

When the heater control board of the cr200j power-concentrated EMU failed, causing uneven temperatures in the carriages and affecting the comfort of passengers, Wang Chao and his team stepped forward to develop a test bench with fearless courage and superb technology. , peeling off the cocoon, and finally found that there are subtle flaws in the design. This discovery of

not only quickly fed back to the manufacturer, promoting the optimization and upgrading of the product, but also demonstrated his pursuit of technological excellence and his high emphasis on passenger experience.

The wheel of time is rolling forward, and it is July 2023 in the blink of an eye. The EMU maintenance work of the China-Laos Railway has encountered a new problem - the main control board failed frequently during the inverter ground maintenance test, which was like the sword of Damocles hanging over the safety of the train.

Faced with possible long-term shutdowns and problems with parts replacement, Wang Chao once again showed his "nimous energy". He led the team to conduct in-depth analysis, dismantle the test bench, verify the circuit day and night, and finally upgraded the test bench, which not only greatly shortened the maintenance cycle, but also won valuable time for the smooth operation of the China-Laos Railway.

In November of the same year, the Laos "Lancang" EMU embarked on its first maintenance trip to China. Wang Chao and his studio members welcomed guests from afar and carefully formulated a detailed maintenance plan for key components.

In two weeks, they efficiently completed the maintenance of key components such as the pis compartment controller, under-car power integrated board, and liquid level sensor, building an impenetrable line of defense for the safe operation of the "Lancang". This professionalism and dedication have not only won high praise from domestic and foreign counterparts, but also brought the maintenance technology of the China-Laos Railway to a new level.

While doing maintenance work, Wang Chao also shoulders the important task of scientific research and technological innovation. He has presided over the completion of 3 scientific research projects and 29 technical research projects, and independently developed more than 20 projects including "board card multi-channel signal multi-channel output and feedback device" and "railway passenger car 39-core communication socket alignment device" Workwear results.

He also participated in the compilation of 7 electrical maintenance operation instructions for the China-Laos railway cr200j power centralized EMU, pushing Chinese technical standards to the international stage and contributing to the technical exchange and cooperation of the China-Laos railway.

One problem is overcome, and another problem comes one after another.

In 2024, on-board mechanics reported that the undervoltage board of the charger of the cr200j power-concentrated EMU unit was burned out, resulting in no power on board. Wang Chao once again led the team to study the control principles and conduct technical research. After discovering design flaws in the undervoltage board of the charger, he promptly replaced the circuit components and fed back to the manufacturer for optimization.

"Although the passengers do not know us repairmen, we repairmen have to think about the passengers." Wang Chao said that his communication with thousands of passengers is achieved through running trains. More and more people It is his greatest compliment that more passengers choose to travel by train.

According to statistics, since the China-Laos Railway was put into operation in December 2021, as of August 19, a total of more than 55,000 passenger trains have been operated, carrying more than 38 million passengers. In places where passengers cannot see them, Wang Chao uses innovation and dedication, writing a new chapter in China-Laos railway maintenance technology.

Building dreams across borders and building bridges with ingenuity

Wang Chao's skills have not only won widespread praise at home, but also left warm friendships in foreign countries.

In the early summer of 2024, under the night sky in Laos, the China-Laos Railway "Lancang" EMU was parked quietly on the platform, but Chinese technician Xu Wei was anxious. A small socket failure was like an anthill that stood between him and safe operations. In the loneliness and helplessness of a foreign country, he dialed Wang Chao's phone number. Although the

socket is small, its importance cannot be ignored. It is related to passengers’ riding experience and is the key to safe train operation. On the other end of the phone, Wang Chao quickly analyzed the fault situation and proposed a detailed solution: replace the power board and send the faulty parts back to China for in-depth maintenance.

A few days later, the board carrying hope traveled across thousands of mountains and rivers and arrived at the "Wang Chao Skills Master Studio". Here, Wang Chao used his skillful hands to investigate one by one, finally found the source of the fault and successfully repaired the board.

Wang Chao knows very well that the real technological inheritance lies in communication and sharing. In addition to the repair work, he had in-depth communication with Laotian technicians through remote video calls. He patiently answered every question and explained the technical points and maintenance methods in detail." Under his careful guidance, Lao technicians not only mastered the skills to repair similar faults, but also took a substantial step in the field of technical research.

Since the opening of the China-Laos Railway, Wang Chao and his team have always been on the front line of technical support. They have not been afraid of difficulties and have bravely climbed to the top, and have successively helped the Laos Railway Department solve the problem of driving safety monitoring host boards and under-car power supplies. There are more than 20 difficult and complicated problems in the operation of the trains, such as board card maintenance. These achievements and efforts not only ensure the safe operation of the trains, but also deeply impress the Lao colleagues.

In June 2024, four Lao train mechanics were on board. Traveling thousands of miles to Kunming, Yunnan, they visited the Wang Chao Skill Master Studio and had face-to-face discussions with the legendary "Teacher Wang" on the related skills of train maintenance.

In a relaxed and pleasant atmosphere, they not only learned valuable experience. He also formed a profound friendship with Wang Chao. This cross-border friendship is as strong and lasting as the China-Laos railway.

Wang Chao always maintains a normal heart in the face of honors and praises. He often says: "I am just a person." An ordinary railway worker did what he should do. "In his view, every technical research and every cross-border assistance is a reflection of his love and loyalty to the railway industry. He uses his actual actions to fulfill the original intention and mission of a craftsman - striving for excellence and pursuing excellence. .

Wang Chao is the epitome of countless Chinese craftsmen under the "One Belt, One Road" initiative. They have built bridges of friendship and dreams in foreign countries with their superb skills, selfless dedication and firm belief.

These bridges are not only. It connects the economic artery between China and the world, and also conveys the friendship and desire for cooperation of the Chinese people.