Basic composition and function of locomotive bogie As an indispensable part of locomotive, AC bogie has many advantages, such as high power, small size and convenient maintenance, and has become the first choice for mainstream locomotives at present. The basic composition and functions of locomotive bogies are shared below.

The basic composition and function of locomotive bogie 1 The high-speed running of EMU trains is closely related to the bogie of EMU. Let me talk about what a bogie is first. Usually, two or more wheelsets are assembled together with special frames to form a carriage that can directly support the car body. This kind of car is called bogie.

So what is the function of EMU bogies?

Bogies are the most important part of trains for multiple units or ordinary trains. Whether the bogie structure is reasonable or not will directly affect the stability, stability and safety of EMU trains.

For all high-speed trains, high-speed, stable and safe operation is inseparable from bogie technology. Moreover, our common subways and urban rails are inseparable from bogies, which shows how important bogies are for wheel-rail trains.

Function of bogie

There are many functions of bogies, so here is only a brief discussion. The first function is to transmit force, which can also be called bearing, and play the role of bearing the weight of the train;

The second function is cushioning, also called shock absorption, which is mainly to ensure the good stability and stability of the train. The third function is guidance, which can also be called guidance, and plays the role of guiding the train to run on the rails;

The third function is braking. I believe everyone understands this function, and the fifth function opposite is driving.

I want to emphasize one more point about the driving function of the bogie. Not all bogies have drive function, only power bogies have drive function, and non-power bogies have no drive function.

Basic composition of bogie

In order to realize the above five functions, the bogie must have the following basic components. As I said before, the so-called basic components are all necessary, and distributability is not the basic component. Here, I take the bogie of CRH380A EMU as an example, and summarize the basic composition of the bogie into five parts, as shown in the following figure.

Bogie composition

Looking up from the bottom of the bogie, the first one is called wheelset, and the second one is called axle box, in which the wheelset is installed. The third is to connect the axle box with the upper frame.

Also called primary suspension, it mainly includes axle box spring, axle box rotating arm and so on. The fourth part is the framework; Fifth, secondary springs, including air springs and various damping devices, are mainly used to connect the car body and the bogie below.

2. Basic components and functions of locomotive bogies. Bogies are an important part of railway rolling stock. Generally speaking, bogies have the following functions:

Bear the load, that is, bear the load from the bogie, mainly including the weight of the car body, various electromechanical equipment installed inside the car body and passengers, and transfer these loads to the track through elastic suspension devices.

Under the action of the transmission force, the traction force generated by the traction motor or the braking force generated by the braking device is transmitted to the underframe of the car body and then to the coupler through the traction device such as the traction rod, so as to realize the traction and braking of the train. At the same time, it also transmits centrifugal force and lateral force.

Buffer function, the locomotive and rolling stock will have the impact of the line on the vehicle due to the irregularity of the line in the running process. After being buffered by parts such as bogie suspension, the running stability of the vehicle is ensured. Guiding function, through the function of bogie, guides locomotives and vehicles to pass through curves and turnouts smoothly, and ensures the safety of vehicles when running in curves.

The performance of the bogie structure directly determines the traction capacity, running quality, wheel and rail wear and the safety of train operation, so the bogie should meet the following technical requirements:

Ensure that the attachment conditions are in the best condition and the axle load transfer is as small as possible. The dynamic performance is good when running, so as to achieve smaller line force and reduce the stress and wear of tracks and wheels.

Should meet the requirements of lightweight, on the premise of meeting the strength and stiffness, as far as possible to reduce the weight. This simple structure is beneficial to reduce the maintenance workload under the condition of ensuring reliable operation. Bogie composition

As shown in the following figure (CRH2 EMU bogie), the bogie generally consists of the following parts:

CRH2 EMU bogie

Wheelset: directly transfer the weight of the vehicle to the track, generate traction and braking force through the adhesion of the wheel and rail, and realize the running guidance of the vehicle on the line through the rotation of the wheelset. Axle box: ensure the wheelset's rotary motion, make the wheelset adapt to the line conditions, and move up and down, back and forth, left and right relative to the frame.

A series of elastic suspension devices: ensure the uniform distribution of axle load and reduce the influence of line irregularity on vehicles. It mainly includes axle box spring device, axle box positioning device and axle box vibration reduction device. Frame: the frame part of the bogie, which is used to install all parts of the bogie and bear and transmit vertical and horizontal forces.

Secondary suspension device: further alleviate the impact vibration, make the bogie rotate relative to the car body when passing through the curve, and ensure the running stability of the vehicle. It mainly includes secondary spring device, secondary damping device and anti-roll device. Driving device: transmitting the power generated by the power device to the wheelset.

It mainly includes traction motor, transmission device and motor suspension device. 7. Basic braking device: the force transmitted by the brake cylinder is increased according to a certain proportion and then transmitted to the executive mechanism to realize train braking.

The basic composition and functions of locomotive bogies 3 There are many functions of bogies, which are only briefly discussed here. The first function is to transmit force, which can also be called bearing, and play the role of bearing the weight of the train; The second function is cushioning, also called shock absorption, which is mainly to ensure the good stability and stability of the train.

The third function is guidance, which can also be called guidance, and plays the role of guiding the train to run on the rails; The fourth function is braking. I believe everyone understands this function, and the fifth function opposite is driving.

I. Basic functions and requirements of bogies

Transportation: Bogies are used in vehicles to increase the load, length and volume of vehicles and improve the running speed of trains to meet the needs of railway transportation development; Conversion of motion form: under normal operating conditions, the car body can sit on the bogie reliably, and the rolling of the wheels along the track is converted into the translation of the car body along the line through the bearing device;

Bearings: support the car body, bear and transmit various loads and forces from the car body to the wheelset or wheel rail to the car body, and evenly distribute the axle load; Driving stability and safety: ensure the safe driving of vehicles, be able to drive flexibly in a straight line and smoothly pass through curves;

I. Basic functions and requirements of bogies (continued)

Stability and safety: the structure of the bogie should be convenient for the installation of the spring damping device, so that it has good damping characteristics, so as to ease the interaction between the vehicle and the line, reduce vibration and impact, reduce dynamic stress, and improve the stability and safety of vehicle operation;

Traction braking: make full use of the adhesion between wheel and rail to transmit traction and braking force, so that the vehicle has a good braking effect and can stop within a specified distance; Manufacture and maintenance: Bogies are independent parts of vehicles. It is required to minimize the number of connections between the bogie and the car body, with simple structure and convenient disassembly, so that the bogie can be manufactured and maintained independently.