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

Rozważmy łożysko z podwójnym kołnierzem o promieniu otworu 20 milimetrów, doświadczające siły osiowej wynoszącej pięć kiloniutonów.
Kołnierz A, o promieniu 40 milimetrów, przenosi 75 procent siły, podczas gdy kołnierz B, o promieniu 30 milimetrów, przenosi 25 procent; oba kołnierze równomiernie rozkładają nacisk.
Oblicz maksymalny moment tarcia, jaki może wytrzymać łożysko, biorąc pod uwagę współczynnik tarcia statycznego 0,3 dla obu kołnierzy.
Przypomnij sobie wyrażenie określające wymagany maksymalny moment tarcia. Poprzez przegrupowanie i podstawienie wartości sił przenoszonych przez oba kołnierze można określić maksymalny moment tarcia.
Następnie zmodyfikuj konfigurację, wywierając na łożysko siłę osiową 15 kiloniutonów. Określ minimalny moment obrotowy wymagany do pokonania tarcia.
Korzystając z równania momentu tarcia i podstawiając wartości, można wyznaczyć moment dla obu kołnierzy spowodowany siłami tarcia.
Zrównując sumę momentów wokół osi z do zera i podstawiając znane wartości, można określić wymagany minimalny moment obrotowy.

<ol>
	<li>Hibbeler, R.C. (2016). Mechanika inżynierska \u2012 Statyka i dynamika. Hoboken, New Jersey: Pearson Prentice Hall. Strona 454.</li>
</ol>

Łożyska: rozwiązywanie problemów

Bearings: Problem Solving

Rozumienie obliczeń i koncepcji związanych z łożyskami dwukolankowymi jest niezbędne dla inżynierów i projektantów, aby zoptymalizować wydajność tych komponentów w różnych zastosowaniach. Analizując łożysko w różnych warunkach, można zapewnić, że wytrzyma ono siły i momenty, które występują podczas jego pracy. Dzięki tej wiedzy można podejmować trafniejsze decyzje dotyczące projektowania i doboru łożysk do określonych zastosowań. Przyjrzyjmy się łożysku dwukolankowemu o określonych wymiarach i działającym na nie siłach osiowych.

<img alt="Figure 1" src="/files/ftp_upload/14327/14327_PT_Figure_1v2.svg" style="text-align: center; height: 400px;" />

Aby znaleźć maksymalny moment tarcia, który łożysko dwukolankowe może wytrzymać, można użyć następującego wyrażenia:

<img alt="Equation 1" src="/files/ftp_upload/14327/14327_PT_Equation_1v2.svg" style="text-align: center; height: 39px;" />

Aby obliczyć maksymalny moment tarcia, należy przekształcić to wyrażenie i podstawić wartości sił działających na oba kołnierze.

Rozważmy przypadek, gdy na łożysko dwukolankowe działa siła osiowa. Aby określić minimalny moment potrzebny do pokonania tarcia, najpierw obliczamy moment dla obu kołnierzy spowodowany siłami tarcia, używając równań momentu tarcia i podstawiając wartości.

<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;" />

Następnie równoważymy sumę momentów wokół osi z dołączoną wartością. Minimalny wymagany moment do pokonania tarcia w zmodyfikowanej konfiguracji można ocenić.

<img alt="Equation 4" src="/files/ftp_upload/14327/14327_PT_Equation_4v2.svg" style="text-align: center; height: 13px;" />

Zrozumienie obliczeń i pojęć związanych z łożyskami z podwójnym kołnierzem jest niezbędne dla inżynierów i projektantów w celu optymalizacji wydajności ...

Education

JoVE Core

Mechanical Engineering

Inżynieria mechaniczna

Unit 1

Jednostka 1

Friction

Tarcie

KEY TERMS AND CONCEPTS

Kluczowe terminy i pojęcia

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

dry friction

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bearings: problem solving

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...

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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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mechanical engineering

Double-Collar Bearing Torque Calculations

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