Diploma project - Improvement of the brake chamber

Contents

INTRODUCTION

1 ANALYSIS OF PRODUCTION ACTIVITIES OF UGATP-4 BRANCH OF STATE UNITARY ENTERPRISE BASHAVTOTRANS

1.1 General characteristics of the enterprise

1.2 Organization and technology of repair of machines in the workshop of UGATP -

1.2.1 Characteristics of the production building

1.2.2 Repair technology of UGATP vehicles -

1.2.3 Organization of technical control

1.3 Technical and economic performance indicators of UGATP

1.4 Conclusions on analysis and project objectives

2 REVIEW AND ANALYSIS OF STRUCTURES OF BRAKE CHAMBERS WITH SPRING POWER ACCUMULATOR

2.1 Pneumatic power accumulator of spring piston type

2.2 Combined brake chambers with spring energy accumulator

2.2.1 Spring energy accumulator with mechanical release device without force spring deformation

2.2.2 Spring energy accumulator with hydraulic release device

2.2.3 Brake chamber with spring energy accumulator of type 12/20 of LiAZ bus

2.3 Conclusions

3 IMPROVED DESIGN OF KAMAZ CAR SPRING POWER ACCUMULATOR

3.1 Diagram and principle of operation of proposed structure

3.2 Advanced Energy Storage Design Management

4 CALCULATION OF PARTS OF IMPROVED BRAKE CHAMBER WITH SPRING POWER ACCUMULATOR

5.1 Calculation of fixing mechanism strength

5.2 Calculation of screw pair of mechanical release device

5.3 Calculation of rivet joint of piston guide

5.4 Calculation of rivet connection of electromagnet housing

5.5 Calculation of retainer spring

5.6 Calculation of electromagnet for piston locking mechanism control

5.6.1 Calculation of magnetic core parameters

5.6.2 Calculation of electromagnet winding parameters

5 DEVELOPMENT OF MAINTENANCE PLAN OF KAMAZ VEHICLE BRAKING SYSTEM

6 PROJECT SAFETY AND ENVIRONMENTAL FRIENDLINESS

6.1 Ensuring working conditions and safety at work

6.2 Environmental protection measures

6.3 Measures to protect the population and material assets in emergency situations

7 TECHNICAL AND ECONOMIC EFFICIENCY OF PNEUMATIC DRIVE WITH IMPROVED ENERGY ACCUMULATOR

7.1 Calculation of Design Implementation Cost Item

7.2 Calculation of revenue from project implementation

7.3 Calculation of economic efficiency indicators

CONCLUSION

BIBLIOGRAPHY

Introduction

The qualitative change in the vehicle fleet associated with an increase in the mass and speed of vehicles has led to a tightening of the requirements for driving systems. In particular, such systems include the braking system of automobiles.

The dieselization of vehicles made the use of vacuum brake amplifiers too difficult. This was one of the reasons that at present many factories producing heavy vehicles and buses use pneumatic brake drives.

The constant process of complicating the design of the car could not but affect the braking system. Currently, the vast majority of trucks are produced with second-generation pneumatic drives. These are so-called multi-circuit braking systems that meet UNECE Regulation No. 13 as well as domestic road safety requirements. The need to fulfill numerous and stringent requirements has led to the fact that the drive was complicated by numerous devices, highways and controls.

A similar brake drive is installed on KamAZ cars. The multi-circuit braking system of the KamAZ family of cars meets such requirements as monitoring the brake circuits of the tractor and trailer, parking braking by spring energy accumulators, adaptability to various types of trailers and ensuring control over the condition of the brake drive.

With the indicated positive qualities of multi-circuit brake drives of the KamAZ family of cars, the most frequent malfunctions are air leaks due to violation of sealing rings, cuffs, breakdown of pneumatic drives, freezing of moisture in the drive at negative temperatures. Attention should be paid to the malfunctions of the parking braking circuit, since the technical and economic indicators of the car and traffic safety depend on its operation.

During operation, in energy accumulators, the seals of the piston in the cylinder and the pusher pipes in the body wear and fail, which leads to braking of the car and, as a result, increased fuel consumption and wear of the brake mechanism. When the pneumatic lines that supply compressed air to the energy accumulators for releasing the car break, the parking brake is actuated during movement, which can lead to an emergency situation and a traffic accident. The need to constantly supply compressed air to the energy accumulators during the movement of the car leads to the fact that the compressor is in working condition for a significant time, making up the parking circuit. In this case, the loaded parts of the compressor wear.

In order to reduce compressor wear and prevent some operational failures, the diploma design proposes the modernization of the parking braking system, in particular the structure of the spring energy accumulator and the method of control named. Its structural difference is the use of a fixing mechanism with a remote release device. As a result, the risk of an emergency on the road is reduced, the process of emergency release is simplified.

Characteristics of the production building

Year of construction - 1974;

- foundation - prefabricated, reinforced concrete;

- walls and their external decoration - panel, ceramic concrete on reinforced concrete columns;

- partitions - brick;

- slabs - reinforced concrete slabs;

- roof - combined, soft, roll;

- floors - concrete, asphalt concrete, ceramic tiles;

- openings: window - metal bindings, blind;

door - metal;

- interior decoration - plaster, whitewash, tiles;

- sanitary and electrical devices:

heating - steel pipes;

water supply - steel pipes;

sewage - cast iron pipes;

electric lighting - available;

ventilation - available;

telephone - internal;

Colon grid: 12· 18

The production building includes the following areas and rooms:

1) Maintenance area

2) Mednitsky workshop

3) Electrical equipment repair area

4) Welding shop

5) Engine shop

6) Aggregate section

7) Area of washing of units and units

8) Rotable warehouse

9) Diagnostic area

10) Fuel equipment repair area

In the repair area of ​ ​ UGATP-4, the current repair of all rolling stock is carried out. Repair of engines, transmission units, undercarriage, repair of electrical equipment, body repair, etc.

To carry out these types of repairs, there is an ongoing repair zone with posts and sections. They employ the production workers of the relevant specialties and qualifications - in the amount of 28 people.

Repair technology of UGATP-4 vehicles

A car requiring repair comes from the line to the OTC checkpoint, where the OTC technician on duty performs an inspection and preliminary inspection. He also makes an application for repairs indicating the brand of the car, its state number and the reason for setting for repairs. The application is transferred to the duty mechanic of the repair zone, and the car goes to his disposal. At his direction, the driver sets the car to one of the posts in the maintenance zone.

If it is not necessary to remove the unit from the machine, its repair is carried out directly at the posts, which are equipped with inspection ditches with two rack lifts or at floor posts with four rack lifts.

If necessary, the unit is removed from the car and sent for repair to the corresponding section. Removal of large units is performed by means of autocrane. Before getting to the repair area, the unit undergoes external cleaning from mud and oil deposits. Further cleaning of the unit part is obtained after disassembly in the washing plant with detergent solution (water + caustic soda) in the washing area.

Parts are defected by repairmen, workers and report the results to the shift supervisor.

Repair is carried out mainly either by the method of repair dimensions, or by placing a new part. Using the example of engine repair: crankshafts are repaired by method of repair dimensions, parts of cylinder-piston group - by the same method. Distribution shafts are subjected to the same method.

The repaired engines are run-in only on "hot" run-in stands. There is no "cold" run-in in the workshop of UGAP4. This is a serious disadvantage, since before hot running it is necessary to run the engine in a cold way in order to avoid the formation of bursts on the rubbing surfaces.

When analyzing the existing system of organization and repair in the UGATP4 workshop, it is necessary to note the following shortcomings:

- absence of pre-repair diagnostics of a/m and their units;

- absence of parts defect section with appropriate equipment and accessories;

- absence of process documentation for repair operations at workplaces.

When washing parts, only external washing of parts is performed. The interior cavities and passages remain non-washed, although they must be washed and purged under pressure. Good washing of the parts makes it possible to determine more defects in the defect.

When disassembling units and units, obsolete equipment is used. Existing stands for disassembling units do not allow them to rotate during operation, which greatly slows down the disassembly process.

In case of parts defect, which is performed directly in the repair areas, no modern equipment is used, except for the measuring tool. It is not possible to detect internal defects in this case. Therefore, during assembly, parts are often installed that need to be either rejected or restored.

Assembly of units and assemblies is performed on the same primitive equipment as disassembly. Tools and accessories in many cases do not comply with safety regulations. There are no torque wrenches required to control the tightening torque of the fasteners.

The units as a whole are not run-in after assembly. Only hot running of engines is performed. Appropriate equipment is available for this purpose. But there is no cold rolling process, which must be carried out before hot rolling in order to avoid the formation of bursts on the rubbing surfaces of new and restored parts.

Organization of technical control

Repaired rolling stock leaves the repair zone and is sent to the control and technical point, where the OTC on-duty mechanic checks the quality of repairs. If the quality is unsatisfactory (there are leaks of technical liquids, foreign sounds during the operation of the machine units and assemblies, etc.), the mechanic draws up a return to the repair zone in the appropriate form and sends the bus back to the repair zone. If there are no faults after repair, the bus leaves the line.

Directly in the areas for repair of units, the quality of their repair is determined visually by the master of repair production. At the same time, a measuring tool is used: calipers, micrometers (with an accuracy of 0.01 mm).

Measures to protect the population and property in emergency situations

An emergency (emergency) is understood to mean a situation in a place characterized by uncertainty and complexity of decision-making, the stressful state of the population, significant social, environmental and economic damage and, above all, human casualties, as a result of which it takes a large cost to carry out rescue work and eliminate negative work.

Emergencies can result from accidents at power plants, large chemical, oil refining, metallurgical, biotechnological plants, high-pressure main pipelines, food processing plants, as well as from natural disasters such as earthquakes, floods and fires.

Such phenomena lead to the destruction of communication systems, roads, energy supply, water supply, destruction of property, death.

An emergency situation in the conditions of UGATP - 4 may arise in the event of a fire or explosion at the plant's gas station, fuel and lubricants depot. Therefore, the company has a list of officials responsible for the implementation of preventive measures. The Chief Engineer is the responsible manager of the emergency response at the filling stations. In case of an accident at a gas station, before the arrival of the responsible work manager, the master or operator leads the rescue of people and the elimination of accidents. Persons called to eliminate the accident shall report their arrival to the responsible work manager and, upon his instructions, shall take up their duties.

Responsibilities of Responsible Accident Response Manager:

- Having become familiar with the situation, immediately begin to implement the measures provided for by the operational part of the accident elimination plan and supervise the rescue work;

- organize a command post, inform all performers about its location and is constantly located at it;

- to appoint an assistant to the responsible head of the accident response;

- Check whether the fire department, officials have been called and whether the agencies have been notified according to the alert list;

- to find out the number of people caught by the accident and their whereabouts;

- maintain operational communication with the leadership of the territorial unit of the GPS, etc.

Duties of Assistant Responsible Accident Management Manager:

- Organize the provision of timely medical assistance to victims;

- keep an operational log on accident elimination;

- monitor compliance with industrial safety requirements;

- in case of emergency work for more than 6 hours to organize meals and rest for employees engaged in accident elimination.

Duties of filling station personnel (operator, duty mechanic):

- To inform persons and institutions about the accident, according to

notification scheme;

- call the fire department immediately and inform the UGOCHS IDC of Ufa,

notify the management of the enterprise about the accident;

- if necessary, in order to prevent complications,

disconnection of process equipment, etc.

Responsibilities of the Chief Energy Officer:

- ensure the organization of the team of electrical fitters for the performance of works

elimination of the accident;

- provide, at the direction of the responsible work manager, power switching on and off, normal operation of electromechanical

equipment, serviceability of communication and signalling;

Duties of garage manager:

- at the request of the emergency work manager, allocate a part of the personal

composition;

- prepare forces and means for timely fire elimination,

which may result from an accident;

- provide fire-fighting equipment, tools and

inventory of employees of the enterprise allocated by the responsible manager for the help of fire protection and combat calculation of DPA;

- keep in constant contact with the responsible work manager for

elimination of the accident .

Heads of departments, having received a message about the accident, to conduct

necessary measures according to the accident management plan and inform

about his actions of the responsible work manager.

Therefore, a freight transport enterprise can cause an emergency. As a result, under the conditions of a settlement, this can lead to the loss of material assets, harm to human health and the environment.

Conclusion

As a result of the work done, an improved brake chamber with a spring energy accumulator of the KamAZ car pneumatic drive was designed.

In the improved brake chamber with a spring energy accumulator, a piston fixing device is used. Use of the piston fixing device allows reducing losses of compressed air in the pneumatic drive, unloading the compressor and increasing its life, reducing fuel consumption and improving vehicle traffic safety.

The relative simplicity of the designed design makes it possible to manufacture the design of an improved energy accumulator in the conditions of repair shops of motor vehicles.

In the course of the work, the technology for maintenance of the brake pneumatic actuator was proposed in relation to the designed design.

Cost-effectiveness calculations show that the payback period of the project is 2.6 years.

From the above it follows that the implementation of this project is advisable and profitable.