Poltava TRZ: modernization of diesel locomotives
Today, the task is not only to repair an old locomotive, but also to radically improve it, increase reliability, efficiency, extend service life, and improve the working conditions of locomotive crews and repairmen. As world practice has shown, the most effective way to modernize diesel locomotives is to replace their power plants with more modern ones. After all, the diesel engine of a locomotive wears out and becomes obsolete much faster than its carriage. In this regard, the Poltava Locomotive Repair Plant (TRZ) has established strong partnerships with the Kolomna Plant, the American company General Electric and the Czech company CZ Loko.
Together with the Kolomna Plant, projects have been developed to replace diesel engines that have reached their end of life with new diesel engines of the D49 type. Such projects have been developed for diesel locomotives such as TE10, M62, CHMEZ, TEM2, TEM7 and TGM6. Such modernization of TE10 and M62 type diesel locomotives has been known for quite a long time. The Poltava plant also performs this work for the railways of different countries.
The modernization of the TEM7 and TGM6 shunting locomotives built by the Ludinovsky Plant is of interest. It would seem that these locomotives have already been initially equipped with D49 type diesels. The fact is that diesel locomotives of an early design with a cast-iron crankshaft and its main bearings with a toothed joint were installed on the TEM7 and TGM6A diesel locomotives built in the 70s and 80s, but then more advanced locomotives were created. The TEM7 was replaced by the TEM7A, and instead of the TGM6A, the TGM6B was built, and a little later, the TGM6D. These locomotives were equipped with improved D49 diesels with steel crankshafts, flat—joint bearings, and other changes aimed at improving reliability.
However, locomotives of early construction continue to operate in many industrial enterprises. Their power plants need to be replaced, but a significant redesign of the locomotive as a whole is necessary for the installation of new diesels. For example, the TEM7 diesel locomotive requires the transfer of an exciter, a starter generator, an oil-water heat exchanger, as well as related other design changes. Poltava specialists successfully coped with this task and returned several worn-out locomotives to service, significantly extending their service life.
The second important area of modernization is the reconstruction of TEYU and M62 type diesel locomotives jointly with the American company General Electric. Similar work has been done before, for example, on the railways of Kazakhstan. But before that, diesel and other new equipment locally fitted into the existing body of TEIU diesel locomotives. However, installation is associated with considerable labor intensity. Among other difficulties, this creates problems with the locomotive's suspension. In particular, within the existing body, the cooling device has to be made one-sided. The weight and location of other equipment are changing.
In the new version, the modular principle is used to simplify the solution of the problem, improve the quality and improve the characteristics of the locomotive. In the USA, at the plant of the General Electric company (Erie), a ready-made Super Skid power module is being manufactured. In this module, a 7FDL diesel engine, a traction generator, hardware chambers with electrical equipment, a complete set of auxiliary mechanical equipment, including a compressor, a diesel cooling unit with a fan, and fans for cooling electric machines are installed on a common frame.
The exhaust is equipped with an electronic fuel supply control system. The set of electronic equipment includes the Bright Star microprocessor system, which provides control and diagnostics of locomotive systems. All these onboard devices are covered by the hood.
The power module is being delivered from the USA in full readiness. The equipment that was previously located on the frame is completely dismantled on the upgraded locomotive, only the "native" cabin is preserved. Instead of the removed equipment, a ready-made "Super Skid" power module is installed. It remains to pair the cabin with the power module, make doors for access to electrical equipment and to the platform, and protect the passage around the hood. Thus, the upgraded TE10 and M62 locomotives are being converted into cowled locomotives. The first such locomotives were sent to a private railway in Yakutia.
And finally, the third area of modernization of diesel locomotives was organized with the participation of the Czech company CZ Loko. Until 2006, the company was called "CMKS". The company specializes in the repair and modernization of locomotives in cooperation with the American concern Caterpillar, represented in Europe by Zeppelin. For about ten years, CMKS has been modernizing shunting and mainline diesel locomotives of various series operating on Czech railways
The use of relatively light and high-speed Caterpillar diesel engines on diesel locomotives is consistent with the general global trend. Previously, it was believed that medium—speed engines with a relatively low maximum crankshaft speed of 750-1000 rpm and a sufficiently large cylinder displacement should be used on diesel locomotives with electric transmission. All other things being equal, these diesels have a longer life and better efficiency. But on the other hand, they have significantly more mass than high-speed engines. Since there were no special restrictions on the weight of diesel on shunting locomotives, this disadvantage was not given much importance.
Previously, it was believed that a high—speed diesel engine is a power plant with relatively high power, with small dimensions and weight, but with a small resource. These were the D12 and M756 diesels, which were equipped with some diesel locomotives and diesel trains with hydraulic transmission. But as time passed, the situation changed. First of all, leading companies have worked to improve the reliability and efficiency of their diesel engines.
At the same time, the demand for these engines increased. More and more powerful mining equipment, mining dump trucks, and autonomous power plants appeared, where such engines were widely used. Their capacity exceeded 2000 HP, i.e. far exceeded the parameters required for shunting and even some mainline diesel locomotives. Today, high-speed diesels from the world's leading manufacturers (and Caterpillar also belongs to them) can compete with medium-speed diesel locomotives in the range of shunting locomotives.
As you know, the criterion of expediency is economics. High-speed diesel turns out to be much cheaper to produce. Firstly, a lighter diesel requires less expensive metal. Secondly, high-speed diesels used in a wide variety of industries and construction are produced in large quantities, and the larger the series, the lower the cost of each product.
Therefore, today in world practice, high-speed diesel engines are most often used for shunting diesel locomotives, which are modifications of power plants for general industrial purposes. There is already experience in upgrading ChKD-Prague diesel locomotives, including the CHMEZ type, as well as the M62.
The first diesel locomotive on which the Poltava TRZ carried out such an upgrade was the CHMEZ-1744 diesel locomotive, because locomotives of this series are the most common in Ukraine. The locomotive received the designation CHMEZP. The letter "P" indicates the modernization in Poltava.
During the reconstruction of the CHMEZ-1744 locomotive, everything that stood on the locomotive frame was removed. A diesel generator set "Locat 3512/631" was installed as a power plant as part of a CAT 3512V diesel engine and a Siemens Drasov traction unit flanged to it. Four-stroke, twelve-cylinder, V-shaped diesel engine, cylinder diameter 170 mm, piston stroke 190 mm.
The power of the diesel engine is 1,455 kW (1,980 hp). This is 47% more than the standard K6S310DR diesel engine of the CHMEZ diesel locomotive. At the same time, the working volume is only 51.84 dm3 (l), which is more than three times less than that of a standard diesel engine. One of the reasons for this is that the crankshaft rotation speed is significantly higher than that of traditional diesel locomotives. It varies in the range of 600 — 1800 rpm.
The diesel engine's air supply is provided by two turbochargers. A distinctive feature of diesel engines is the use of pump injectors. The CAT 3512B diesel engine differs from its predecessor, the CAT 3512, by an electronic fuel supply control system. The air enters the diesel turbocharger from the engine compartment through two filters mounted on the sides of the diesel engine. The exhaust muffler is located above the traction unit.
The traction unit consists of two alternators that share a common housing and shaft: a traction generator "Siemens 1FC2 631-6VO 29T" and an auxiliary "Siemens 1FC2 631-6VO 29P". Fastening of the traction unit to the diesel engine frame is flanged. The rotor shaft is connected to the flywheel of the diesel engine by means of an elastic coupling "Centamax". The frame of the diesel generator set is mounted on the frame of the locomotive using 16 elastic rubber-metal blocks.
On the side of the auxiliary generator frame is its GB 112L type exciter, as well as an air conditioner compressor, which receive rotation through a belt drive. The diesel engine kit also includes two charging generators with a voltage of 28 V and two starters designed for a voltage of 24 V DC.
The standard TE-006 traction motors are powered from the traction generator through the rectifier unit. The circuit diagram of traction electric motors has been preserved as standard. Traction motors are connected in three parallel branches, in each of which two electric motors are connected in series. The direction of movement is changed by switching the polarity of the excitation windings of traction motors.
14.11.2022, 17:40
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