Tram device: design and main components. Tram management

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Almost every resident of the city has at least once seen a passing tram or other similar electric transport on its streets. These types of vehicles have been specially designed for movement in such conditions. In fact, the device of the tram strongly resembles ordinary rail transport. However, their differences lie precisely in adaptability to different types of terrain.

History of Appearance

The name itself is translated from English as a combination of a wagon (trolley) and a way. It is generally accepted that the tram is one of the oldest types of passenger public transport, which is still used in many countries around the world. The history of appearance dates back to the 19th century. It is worth noting that the oldest tram was horse-drawn, not electricity. A more technological progenitor was invented and tested by Fedor Pirotsky in St. Petersburg in 1880. Another year later, the German company Siemens & Halske launched the first operatingtram service.

During the two world wars, this transport fell into decay, however, since the 1970s, its popularity has increased significantly again. The reasons for this were environmental considerations and new technologies. The tram was based on electric traction on an overhead contact network. Subsequently, new ways were created to set the car in motion.

Evolution of trams

All species are united by the fact that they run on electricity. The only exceptions are less popular cable (cable) and diesel trams. Previously, horse, pneumatic, gas-powered and steam varieties were also created and tested. Traditional electric trams operate either on an overhead contact network, or powered by batteries or a contact rail.

The evolution of this type of transport has led to its division into types according to purpose, including passenger, freight, service and special. The latter type includes many subtypes, such as a mobile power plant, a technical flyer, a crane car, and a compressor car. For passengers, the design of a tram also depends on the system on which it travels. It, in turn, can be urban, suburban or intercity. In addition, systems are divided into conventional and high-speed, which may include underground tunneling options.

Power supply of the tram

In the early days of development, every service companyinfrastructure, connected its own power plant. The fact is that the networks of those times did not yet have sufficient power, and therefore had to manage on their own. All trams are powered by direct current with a relatively low voltage. For this reason, transferring charge over long distances is highly inefficient from a financial point of view. To improve the network infrastructure, traction substations began to be located near the lines, converting alternating current into direct current.

Today, the nominal voltage at the output has been set at 600 V. Tram rolling stock receives 550 V at the pantograph. In other countries, higher voltage values are sometimes used - 825 or 750 V. countries at the moment. As a rule, tram networks have a common energy economy with trolleybuses, if there are any in the city.

Traction motor description

This is the type most commonly used. Previously, only direct current received from substations was used for power supply. However, modern electronics has made it possible to create special converters inside the structure. Thus, when answering the question of what kind of engine a tram has in its modern version, one should also mention the possibility of using an alternating current-based engine. The latter are better for the reason that they practically do not require any repair or regular maintenance. This applies, of course, only to asynchronous AC motors.current.

Also, the design certainly includes another important node - the control system. Another common name sounds like a device for regulating current through a TED. The most popular and simplest option is considered to be control by means of powerful resistances connected in series to the engine. Of the varieties, NSU, indirect non-automatic RKSU or indirect automatic RKSU systems are used. There are also separate types like TISU or transistor SU.

Number of wheels on a tram

Extremely common today are low-floor variations of this vehicle. Design features do not make it possible to make an independent suspension for each wheel, which requires the installation of special wheelsets. There are also alternative solutions to this problem. The number of wheels depends on the specific version of the tram design and, to a greater extent, on the number of sections.

In addition, the layout is different. Most multi-section trams are equipped with driven wheelsets (which have a motor) and non-driven ones. To increase agility, the number of compartments is also usually increased. If you are interested in how many wheels a tram has, you can find the following information:

1. One section. Two or four driven or two driven and one non-driven pair of wheels.
2. Two sections. Four driven and two non-driven or eight driven pairs of wheels.
3. Three sections. Four driven and non-drivenpairs of wheels in different combinations.
4. Five sections. Six drive pairs of wheels. Two pieces go through one section starting from the first.

Features of driving a tram

It is considered relatively easy, because the transport moves strictly on rails. This means that, as such, manual control from the tram driver is not required. At the same time, the driver must be able to correctly use traction and braking, which is achieved by timely switching between reverse and forward.

The rest of the tram is subject to uniform traffic rules at the time when it follows the city streets. In most cases, this transport has priority over cars and other means of transportation that do not depend on the rail. A tram driver must obtain a driving license of the appropriate category and pass a theoretical exam for knowledge of traffic rules.

General arrangement and construction

The body of modern representatives is usually made of solid metal, and as separate elements it has a frame, frame, doors, floor, roof, as well as internal and external skins. As a rule, the shape narrows towards the ends, thanks to which the tram overcomes curves with ease. The elements are connected by welding, riveting, screws and glue.

In the old days, wood was also widely used, which served as both an element of the frame and a finishing material. In the device of the tram for the currentthe moment preference is given to plastic elements. The design also includes turn signals, brake lights and other means of indicating to other road users.

Coordination and speed indicators

Just like in the case of trains, this transport has its own service for tracking the execution of traffic and the correctness of routes. Dispatchers are engaged in prompt adjustment of the schedule if any unforeseen situation occurs on the line. Also, this service is responsible for releasing reserve trams or buses for replacement.

Urban traffic rules may vary from country to country. For example, in Russia, the design speed of a tram is in the range from 45 to 70 km/h, and for systems with an operating speed of 75 to 120 km/h, building codes prescribe the prefix “high-speed”.

Pneumatic equipment

Cars in their modern design are often equipped with special compressors, which are based on pistons. Compressed air is very useful for several regularly performed operations at once, including actuating door drives, brake systems and other auxiliary mechanisms.

The presence of pneumatic equipment is optional. Due to the fact that the tram device assumes a constant supply of current, these structural elements can be replaced with electrical ones. This greatly simplifies the maintenance of systems, but inthe total cost of producing one car increases to some extent.