This "May 1st" holiday, the railway catenary was invaded by foreign objects and accompanied by strong winds.
In just four days, the Beijing-Guangzhou high-speed rail, Beijing-Tianjin intercity, Beijing-Shanghai high-speed rail, Beijing-Harbin railway line, and Tianjin-Shan line power supply contact network have been "recruited."
These messy foreign objects include agricultural mulch, color steel plates, and dust nets.
Why is the railway catenary so afraid of strong winds and "foreign objects" intrusion?
Is the catenary really "fragile"?
Is there any way to protect it?
How to keep the "safe red line" along the high-speed rail?
Railway professionals gave a detailed explanation to reporters.
Hot Issues:
1. Why is the high-speed rail catenary so afraid of strong winds and "foreign objects" intrusion?
He Chenglin, deputy head of the Catenary Technology Section of the Beijing Power Supply Section, told reporters that electricity is the only driving force for the operation of high-speed trains.
The high-speed rail catenary is also an important part of the power source of the EMU. During normal operation, the voltage of the catenary electric equipment to ground is 27,500 volts.
In terms of material type, there are two types of foreign matter that affect the contact net: one is conductive foreign matter, such as tin foil, kite wire with metal wire, etc. If one end touches the power supply line and the other end is grounded, it will cause The catenary is short-circuited and tripped, which causes the EMU to lose power; the other is an insulating foreign body, although it does not conduct electricity, once it intrudes into the pantograph dynamic envelope of the high-speed EMU, it can also cause the pantograph to malfunction instantly. As a result, the EMU cannot obtain current from the catenary, resulting in no electricity in the EMU.
According to He Chenglin, once these foreign bodies invade, there are generally two solutions.
For large foreign objects, it is necessary to first stop the train on the line, cut off the catenary equipment, and traction power supply professionals to enter the railway protection network, and manually clean up after taking appropriate safety measures. Especially large foreign objects often need to mobilize the catenary. Operation vehicle assisted operation.
This type of operation may take a little longer and have a greater impact.
For relatively small and light objects, professionals can also board the EMU and ride in the reverse direction to the point of failure for manual operation. This type of failure can be handled quickly.
In addition, if some very small foreign objects do not have a great impact on the operation, the pantograph will be used to move the bow down, and then the bow will be lifted and flowed after passing through the point of the foreign body to reduce the impact on the operation.
2. Is the catenary really "fragile"?
The reporter learned that the catenary equipment itself is relatively stable, and the current problem is that there are too many and unstable external risk factors.
For example, He Chenglin said that the power supply section is responsible for the management of "lurking" light objects along the line. These light objects include dust-proof nets on construction sites, plastic greenhouses in rural areas, plastic packaging bags for vegetable markets, and even handle many kite lines every year.
"These foreign objects are extremely dynamic and difficult to control. After all, except for some tunnel sections, the railway is an open-air environment. There are various hidden dangers when passing through urban areas and villages."
According to reports, at present, the railway department mainly relies on civil air defense for the disturbance of foreign objects, and patrols and inspects foreign objects by regularly arranging personnel to patrol along the line and boarding locomotives.
The reporter learned that the scientific research unit is studying, through the comparison and analysis of satellite images, to determine the newly added "lurking" light floating objects along the railway line, so as to study and judge in advance to increase the prompting efforts.
3. How to keep the "safety red line" along the high-speed rail?
Why do foreign bodies frequently invade the railway catenary in windy weather?
In fact, the railway department has a clear "safe red line" requirement. According to the "High-speed Railway Safety Protection Management Measures" jointly issued by the Ministry of Transport and other seven departments, no kite flying or flying is allowed within 500 meters on both sides of the high-speed railway line. Floating objects such as balloons and sky lanterns shall not use offensive equipment such as crossbows, slingshots, and air guns to engage in acts that may endanger the safety of high-speed railways.
At the same time, within this 500-meter range, the proprietor or actual controller of the plastic greenhouses, colored steel sheds, billboards, dust-proof nets and other light buildings and structures on both sides of the line shall take reinforcement and protection measures and take measures to protect the plastics. The construction and construction materials such as film, tin foil, color steel tile, iron sheet, etc. are cleaned up in time to prevent the high-speed railway from endangering the safety of high-speed railways under windy weather conditions.
Ren Daxing, Section Chief of the Comprehensive Treatment Internal Protection Section of the Beijing Public Works Section, told reporters that the internal railway divides the objects that may affect the catenary into light floating objects and hard floating objects, of which the public works section is responsible for "latent" hard floating objects such as color steel plates along the section. Property management.
Since the release of the gale warning on April 30, fifty to sixty people walked around different work areas every day in this section alone. At the same time, they also patrolled through the “additional” locomotive method to discover problems in time and eliminate potential safety hazards.
Ren Daxing said frankly that although the railway department has established a ledger for regular surveys of the color steel sheds that exist along the line, many construction units of this type of buildings are dynamically changing, and the construction costs are also very low. "There is no inspection today, and suddenly tomorrow. It's coming out." Because the "red line awareness" of individual local government departments and construction companies is not strong, the reinforcement measures are often not in place, which creates a safety hazard that affects the operation of the railway.
In addition to the color steel plates, the dangerous trees near certain sections of the railway are also a problem for Ren Daxing. However, in daily inspections, some local management departments do not pay attention to them and do not cooperate with the railway departments.
"Railways are enterprises after all, and if management measures are really in place, local government departments must pay attention to them and work together to increase law enforcement," said Ren Daxing.
The reporter learned that not only the high-speed railway currently has a catenary, but because of the large-scale electrification of the general-speed railway, the normal operation of the catenary is also required. Therefore, the environmental safety along the line should also be paid attention to.
Reporter Sun Hongyang