Reliability Analysis and Optimization for the Brake Drum

In order to research the static and dynamic characteristics of drum brake in the braking process and avoid resonance, it is necessary to carry out static analysis and modal analysis of drum brake. By establishing the three-dimensional model of the brake drum and imported to ANSYS for static analysis, the maximum equivalent stress and maximum deformation of the brake drum are obtained. The first, second and third natural frequencies and modal vibration shapes of the brake drum are obtained by modal analysis. Four dimensional parameters are selected as design variables, and the sensitivity is carried out by using experimental design. Taking the maximum deformation, first natural frequency, second natural frequency and mass of the brake drum as the objective function, the multi-objective optimization algorithm is used to optimize the design variables. Based on the optimization design, the six sigma reliability analysis of the brake drum is carried out, and the six sigma reliability analysis method is given in detail. The cumulative distribution graph of the maximum deformation, first natural frequency, second natural frequency and mass of the brake drum are obtained. The analysis results show that the reliability of the brake drum is close to 100%, and then it is judged that the brake drum has high reliability. The research results provide a reference basis for structural reliability analysis.

The Friction and Wear Influence of Laser Processing Bionic Brake Drum Unit on the Brake Pad

This article starts with the analysis of the contact between the laser processing bionic brake drum unit body and the brake pad and performs the analysis of the force between the unit body and the brake pad based on elastic mechanics and contact mechanics. By using the Preston equation, the wear of the brake pad caused by the unit body is obtained, as well as the relevant factors and influence rule which affects the wear of the brake pad are found. During laser processing on the bionic brake drum unit body, in order to reduce wear of brake pad, the height of the unit body should be minimized. Besides, the light intensity at the centre of the laser spot should be reduced, and the laser intensity distribution should be more uniform, which can effectively improve the environmental friendliness of the brake drum.

Structural and Thermal Analysis of Brake Drum

The brake drum is a specialized brake that uses the concept of friction to decelerate or to stop the vehicle. The deceleration is achieved by the assistance of the friction generated by a set of brake shoes or pads. During the brake operation heat is ejected out this causes damage to the brake. Disc (Rotor) brakes are exposed to large thermal stresses during routine braking and extraordinary thermal stresses during hard braking. To satisfy this condition the drum material should possess a high thermal conductivity, thermal capacity and high strength .The common material used for construction of brake drum is cast iron. The aim of the project is to design, model a disc. Modeling is done using catia. Structural and Thermal analysis is to be done on the drum brakes using four materials Stainless Steel, gray Cast iron, carbon carbon composite & aluminum metal matrix. The shoes of this kind of brake are contained within the drum and expand outwards when the brake is applied. Such kind of brakes is used in medium heavy-duty vehicles. Structural analysis is done on the drum brake to validate the strength of the drum brake and thermal analysis is done to analyze the thermal properties. Comparison can be done for deformation; stresses, temperature etc. form the three materials to check which material is best. Catia is a 3d modeling software widely used in the design process. ANSYS is general-purpose finite element analysis (FEA) software package. Finite Element Analysis is a numerical method of deconstructing a complex system into very small pieces (of user-designated size) called elements.

Experimental study of wear of friction pairs of brake assemblies of transport vehicles

В ряде научно-исследовательских работ, связанных с повышением тормозной эффективности транспортных машин, рассматриваются вопросы уменьшения тепловой нагруженности их тормозных механизмов при помощи принудительного охлаждения путем подачи сжатого воздуха между тормозными колодками и тормозным барабаном в процессе торможения. При этом в данных работах не изучен вопрос влияния подачи сжатого воздуха между тормозными колодками и тормозным барабаном в процессе торможения машины на степень износа фрикционных поверхностей барабанного тормозного механизма. Объектом экспериментального исследования стали тормозные механизмы барабанного типа при подаче к ним сжатого воздуха. Предметом исследования стали полученные результаты процесса изнашивания фрикционных поверхностей тормозных механизмов. В ходе эксперимента получены данные величины износа фрикционных поверхностей барабанно-колодочного тормозного механизма при подаче на них сжатого воздуха. Приведена графическая зависимость износа экспериментальных и не экспериментальных колодок от количества повторений на рабочем органе и давления жидкости в тормозной системе. Функциональный анализ полученных эмпирических закономерностей указывает на то, что факторы, участвующие в исследуемых процессах имеют сложную физическую связь. Кроме того, существующие аналоги исследуемых явлений очень многогранны и неоднозначны. Структурное рассмотрение полученных результатов с учетом существующих в смежных областях закономерностей позволяет утверждать однозначный результат использования найденных соотношений. Установленные зависимости показателей процесса изнашивания фрикционных пар во время принудительного охлаждения их поверхностей на практике могут способствовать повышению эксплуатационной эффективности исследуемой системы. В реальных условиях эксплуатации использование полученных результатов может обеспечить положительный эффект: уменьшение износов элементов конструкции, снижение энергоемкости процессов и, как следствие, повышение надежности действия элементов исследуемой системы. A number of research papers related to improving the braking efficiency of transport vehicles are addressed the issues of reducing the thermal load of their brakes with forced cooling by supplying compressed air between the brake shoes and brake drum during braking. At the same time, the issue of the effect of compressed air supply between the brake shoes and the brake drum during the vehicle braking on the degree of wear of the drum brake mechanism friction surfaces has not been studied in these papers. The drum-type braking mechanisms with compressed air supplying to them became the experimental study object. The obtained results of wearing of the brake mechanism friction surfaces are the subject of the research. The experimental data of the degree of wear of the friction surfaces of the drum-shoe brake mechanism when compressed air is supplied to them are obtained. The functional dependence of the wear of experimental and non-experimental shoes on the number of repetitions in the working body with the implemented required fluid pressure in the brake system is provided. The functional analysis of the obtained empirical regularities indicates that the factors involved in the processes under study have a complex physical relationship. In addition, the existing analogues of the studied phenomena are very versatile and ambiguous. Structural consideration of the obtained results, taking into account the patterns existing in related fields, allows us to state a unique result of using the found relations. In particular, the established dependences of the indicators of the friction pairs wearing using forced cooling can contribute, in practice, to increase the operational efficiency of the system under study. In real operating conditions, usage of the obtained results can provide a diverse positive effect: reduction of wear of structural elements, decrease of the process energy intensity and, as a result, increase of reliability of the elements of the system under study.