Name: double-collar bearing torque calculations
Uploaded: 2023-09-22T11:49:30.000Z
Duration: 1 min 24 s
Channel: JoVE

Considere um rolamento de colar duplo com um raio de furo de 20 milímetros, experimentando uma força axial de cinco quilonewtons.
O colar A, com um raio de 40 milímetros, carrega 75% da força, enquanto o colar B, com um raio de 30 milímetros, carrega 25%; ambos os colares distribuem a pressão uniformemente.
Calcule o momento de atrito máximo que o rolamento pode resistir, dado um coeficiente de atrito estático de 0,3 para ambos os colares.
Recupere a expressão para o momento de atrito máximo necessário. Ao reorganizar e substituir os valores das forças suportadas por ambos os colares, o momento de atrito máximo pode ser determinado.
Em seguida, modifique a configuração exercendo uma força axial de 15 quilonewtons no rolamento. Determine o torque mínimo necessário para superar o atrito.
Usando a equação do momento de atrito e substituindo os valores, o momento para ambos os colares causado pelas forças de atrito pode ser determinado.
Igualando a soma dos momentos em torno do eixo z a zero e substituindo os valores conhecidos, o torque mínimo necessário pode ser determinado.

<ol>
	<li>Hibbeler, R.C. (2016). Engenharia Mecânica \u2012 Estática e Dinâmica. Hoboken, Nova Jersey: Pearson Prentice Hall. Pág. 454.</li>
</ol>

rolamentos: resolução de problemas

Bearings: Problem Solving

Compreender os cálculos e conceitos relacionados aos rolamentos de dupla gola é fundamental para engenheiros e projetistas otimizarem o desempenho desses componentes em diversas aplicações. Ao analisar o rolamento em diferentes condições, é possível garantir que ele possa suportar as forças e momentos experimentados durante a operação. Esse conhecimento possibilita uma tomada de decisão melhor ao projetar e selecionar rolamentos para propósitos e configurações específicas. Considere um rolamento de dupla gola com dimensões específicas e uma força axial aplicada a ele.

<img alt="Figure 1" src="/files/ftp_upload/14327/14327_PT_Figure_1v2.svg" style="text-align: center; height: 400px;" />

Para encontrar o momento de fricção máximo que o rolamento de dupla gola pode suportar, pode-se utilizar a seguinte expressão:

<img alt="Equation 1" src="/files/ftp_upload/14327/14327_PT_Equation_1v2.svg" style="text-align: center; height: 39px;" />

O momento de fricção máximo pode ser calculado reorganizando a expressão e substituindo os valores das forças suportadas por ambas as golas.

Considere um cenário em que a força axial aplicada no rolamento de dupla gola aumenta. Para determinar o torque mínimo necessário para superar a fricção, primeiro calcule o momento para ambas as golas, causado pelas forças de fricção, utilizando as equações de momento de fricção e substituindo os valores.

<img alt="Equation 2" src="/files/ftp_upload/14327/14327_PT_Equation_2v2.svg" style="text-align: center; height: 39px;" />

<img alt="Equation 3" src="/files/ftp_upload/14327/14327_PT_Equation_3v2.svg" style="text-align: center; height: 39px;" />

Em seguida, iguale a soma dos momentos em relação ao eixo-z a zero e substitua os valores conhecidos. O torque mínimo necessário para superar a fricção na configuração modificada pode ser avaliado.

<img alt="Equation 4" src="/files/ftp_upload/14327/14327_PT_Equation_4v2.svg" style="text-align: center; height: 13px;" />

Rolamentos: Resolução de Problemas

Compreender os cálculos e conceitos relacionados aos rolamentos de colar duplo é essencial para engenheiros e projetistas otimizarem o desempenho de ...

Education

JoVE Core

Mechanical Engineering

Engenharia Mecânica

Unit 1

Unidade 1

Friction

Atrito

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

double-collar bearing torque calculations

Double-collar bearing torque calculations show how friction and axial force affect bearing performance. Engineers use these calculations to test whether the bearing can handle the forces and moments it experiences during operation. This helps them choose and design bearings for specific applications and setups.

For a double-collar bearing with set dimensions and an axial force applied, the maximum frictional moment can be found with a standard expression. The equation is rearranged, and the forces supported by both collars are substituted into it. This gives the greatest frictional moment the bearing can withstand under that condition.

The same method also helps when the axial force on the double-collar bearing increases. First, the frictional moment for each collar is calculated from the frictional force equations. Then the moments about the z-axis are set equal to zero, and the known values are substituted. From this, the minimum torque needed to overcome the friction in the modified case can be determined.

Double-Collar Bearing Torque Calculations

double-collar-bearing-torque-calculations

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key terms and concepts

Learn how frictional moment and axial force are used to solve double-collar bearing problems, including maximum moment and minimum torque calculations.

Double-Collar Bearing Torque Calculations | JoVE K12

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Double-Collar Bearing Torque Calculations

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