“Roller Bearing is Outdated”-Russian railways
(Gudok.ru) At the 71st meeting of the Council on Rail Transport of the CIS Member States, which begins in Minsk tomorrow, the proposal of the Russian Ministry of Transport as a regulatory national body to replace roller bearings with cassette bearings in the Russian railway network will be discussed.
Recall that the decision on the mandatory equipment for the overhaul of freight cars with cassette bearings from January 1, 2021 was made at the 68th Commission of the Carriage Management of the Council on Rail Transport of the Member States of the Commonwealth, held in September. Members of the Commission for Traffic Safety of the CIS Rail Transport Council, which was also held in Dushanbe, also spoke in favor of switching to a new type of bearings.
The issue of the mandatory use of cassette bearings in the 1520 space is regulated by the requirements of the “Guidance document on repair and maintenance of wheelsets with axle boxes of freight cars of 1520 gauge main railways (1520 mm)”, adopted on the territory of the countries of the Council for Railway Transport. The decision agreed on by the commissions of the Council on making appropriate changes to this document is on the agenda of the 71st meeting of the Council.
After approval, the need to replace roller bearings with cassette bearings will come into force only in Russia, which is specifically stipulated in the amendments to the document. The railway administrations of other states are not yet ready for similar changes.
As the head of VRK-3, Alexey Bragin, explained, the effectiveness of replacing roller bearings with cassette bearings is beyond doubt.
“Today, 77% of all releases to the current uncoupling repair (TOR) occur due to malfunctions in the axle box assembly, and a car with wheelsets equipped with cassette bearings detaches five times less. Such malfunctions affect traffic safety, ”he said. “The roller bearings are out of date.”
In 2018, uncoupling due to malfunction of axlebox assemblies with roller bearings amounted to 35 cases per thousand, and with cassette – seven cases. The warranty service life of roller bearings is three years, and cassette – 16 years. With the now established frequency of conducting an average repair of a wheelset of five years, the presence of roller bearings in their configuration reduces this time to three years, after which external intervention is required and the manufacturer’s warranty is removed.
The Department of Wagon Management notes that the operation of cassette bearings reduces the wear of the wheel flange and allows them to be used with a guarantee of up to eight years with the bearing, and without them only three years. Now 89% of the fleet of freight cars of the home registry of the Russian Federation (1.148 million as of September 1, 2019) use roller bearings, which,
According to Andrei Rogozin, Deputy Director General of VRK-1, “Hoots”, “problems in the roller bearing, unlike other malfunctions, occur during movement, which causes the axle box to glare, an alarm about malfunctions will stop the train for inspection.
“And this is a technical malfunction of the most difficult of the first and second categories, which lead to a delay in the compositions, and this is the main reason that leads to such dire consequences for the movement,” says Andrei Rogozin. “For example, for VRK-1, the share of such cut-offs in the ASEZ is 78%.
According to the monitoring of hardware failures for the seven months of 2019, which is carried out by the Russian Railways Department of Carriage Management, 50% of all failures were accounted for by the axle box assembly, and in it more than 70% was a malfunction in the mechanical end of the bearing.
Now, cassette bearings are mainly installed on innovative wagons, which have a significant reduction in uncoupling in the TOP compared to conventional ones. As Vostok1520 Deputy General Director for Technical Development Vostok1520, Dmitry Losev, said at a roundtable in September at Gudka, he compared the work of new-type wagons of the same type produced by the Tikhvin Car-Building Plant with cassette and roller axle boxes.
According to the failures of technical means when following the train on the training ground, the reliability of the cassette bearing was 23 times higher, which is very important in conditions of high traffic load. At the same time, the cost of owning a wheelset on a cassette box per 1,000 km was almost five times lower.
“A detailed roadmap for the implementation of this measure has now been prepared and a working group has been created that will consider all issues of transferring to cartridge bearings. The task is complex, and we estimate its solution period in the period of 10-15 years, although, for example, in China it took only three years, ”says Mikhail Sapetov, head of the carriage department of the Central Infrastructure Directorate.