EXPERIENCE OF APPLICATION AND PROSPECTS OF IMPLEMENTING CASTING TECHNOLOGY IN THE HTS OF RAILWAY ROLLING STOCK PARTS

In recent decades, revolutionary changes have been observed in the development of railway transport. The speeds of passenger and freight railway transport have increased several times. During their movement, the noise of the wheelset has decreased, the shock absorption systems, as well as the coupling mechanisms of the carriages have improved. Due to this, the conditions for passengers during the movement of trains have improved in modern passenger carriages.

Although most of the components of railway transport ensure efficiency, reliability, and convenience of railway transport, they in turn operate under extreme loads, wear, corrosion, shock, vibration, significant temperature changes, etc. All this affects the duration of their service life.

The most popular nomenclature of railway transport parts is side frames (Fig. 1, a), spring beams (Fig. 1, b), brake shoes (Fig. 1, c), parts of automatic coupling mechanisms (Fig. 1, d), automatic coupling absorbers (Fig. 1, e), rail joints, crosses (Fig. 1, e), switch transfers (Fig. 1, g), traction clamps, axle box parts, fasteners, axles, wheels, bushings, etc.

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Figure 1 – Examples of the most popular railway transport parts

It is known that the reliability of railway transport and, as a result, the safety of transportation depends on the correct design of the listed parts, the choice of appropriate structural materials with a given set of operational and mechanical characteristics (properties), as well as effective and cost-effective technology for their manufacture.

Foundry production remains the traditional method of manufacturing a wide range of cast parts (castings) for railway transport.

In turn, today there remains a trend towards the use of new progressive casting technologies to obtain high-quality castings in railcar construction.

Among the existing casting methods for this range of parts, it is worth noting the promising application of the technology of manufacturing castings in molds from cold-hardening mixtures (CHC).

The use of casting technology in railway transport can reduce production costs by using fewer materials compared to other casting methods, and produce castings of complex shape (configuration, size, dimensions) that are difficult or impossible to manufacture by other methods, especially for complex parts, such as the “Side frame” casting, “Superstructure beam”, auto clutch parts, brake systems, etc.

In addition, the components used to manufacture HTS can ensure rapid hardening of the mixture, which in turn can speed up the production cycle of casting molds and cores, and as a consequence, increase the serial production of cast parts.

Furthermore, HTS can provide castings with high dimensional accuracy and high-quality surface, which minimizes further machining operations. HTS can also be used for a wide range of alloys, including aluminum, copper, cast iron and steel, during the manufacture of both small and large parts.

Today, in Ukraine, the production of parts for railway transport (carriage building, heating and electric locomotive building) is carried out by a number of enterprises that, despite the crisis situation in the country, find opportunities to modernize their production by introducing the technology of casting in the CHTS into their foundry shops and sections.

In the practice of some enterprises (companies) of Ukraine, when manufacturing railway transport parts, including such complex ones as the “Side frame”, “Overhead beam”, “Coupling mechanism”, other alternative methods are used, namely: casting from gasified models, vacuum film forming technology (VPF) or V-process, casting in sand-clay, as well as sand-liquid glass mixtures.

However, when using the listed casting methods, there are still many problems associated with the formation of defects in castings, namely: sinks, porosity, burning, underfilling, size mismatch, etc. In addition, there are other difficulties that include the organization of the technological process itself for the production of cast railway transport products.

Therefore, recently, information has increasingly appeared in various technical literary sources regarding the feasibility and prospects of using casting technology in railway transport, including the production of cast parts for railway transport, both at enterprises in Ukraine and abroad.

The practice of most enterprises has already confirmed that when implementing the casting technology in the railway transport, effective results are achieved in the production of high-quality castings with a given set of mechanical and operational properties. In addition, this method is universal and can be recommended for the manufacture of a wide range of cast parts. All this is also and additionally confirmed by the relevant documents of manufacturers of railway transport parts, including protocols and reports of testing parts during their operation.

Specialists of UKRFAVORIT LLC take a direct part in the development and implementation of casting technologies in the chemical industry, relevant equipment, and support all stages from design to the final result of implementation at enterprises.

За детальною інформацією і допомогою у підборі матеріалів, а також консультацій щодо рекомендацій їх застосуванням для лиття деталей залізничного транспорту в ХТС звертайтесь до технічних фахівців компанії, координати яких наведено на сайті ТОВ «УКРФАВОРІТ».

UKRFAVORIT LLC invites all interested specialists from enterprises, companies and other organizations to cooperate!