Name: hydraulic hoist force analysis
Uploaded: 2023-09-22T11:49:25.000Z
Duration: 1 min 26 s
Channel: JoVE

Considere uma talha hidráulica que suporta uma carga.
Assumindo uma representação esquemática simplificada desta estrutura de pórtico, que força está a atuar nas barras BD e BF, desde que as dimensões da barra e o peso da carga sejam conhecidos?
Aqui, BF e BD são dois membros da força, enquanto EFG e EDC são membros de várias forças.
Um diagrama de corpo livre para o EFG do membro indicando todas as forças é desenhado.
Os componentes vertical e horizontal da força FBF podem ser expressos usando um triângulo de inclinação.
A condição de equilíbrio de momento na junta E dá a força F BF .
Em seguida, aplicando a condição de equilíbrio da força horizontal na junta E, a força de reação horizontal em E é avaliada.
Da mesma forma, a condição de equilíbrio da força vertical fornece a força de reação vertical na junta E.
Agora, desenhando um diagrama de corpo livre para o membro EDC, os componentes da força ao longo do BD podem ser expressos usando outro triângulo de inclinação.
Aplicando a condição de equilíbrio de momento no ponto C, calcula-se a força F BD.

<ol>
	<li>Hibbeler, R.C. (2016). Engenharia Mecânica \u2012 Estática e Dinâmica. Hoboken, Nova Jersey: Pearson Prentice Hall. Pág. 305.</li>
	<li>Cerveja, F.P.; Johnston, E.R.; Mazurek, D.F; Cromwell, PJ e Self, BP (2019). Mecânica vetorial para engenheiros \u2012 estática e dinâmica. Nova Iorque: McGraw-Hill. pág. 330</li>
	<li>Meriam, J.L., Kraige, L.G., e Bolton, J.N. (2020). Engenharia Mecânica \u2012 Estática. Hoboken, Nova Jersey: John Wiley. pág. 200</li>
</ol>

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armações: resolução de problemas ii

Considere um guincho hidráulico que suporta uma carga de 1 kN. Supondo uma representação esquemática simplificada dessa estrutura de armação, a força atuando nos membros BD e BF pode ser determinada.



<img alt="Figure 1" src="/files/ftp_upload/14292/14292_PT_Fig_1v2.svg" style="text-align: center; height: 350px;" />



As dimensões dos membros e o peso da carga são parâmetros conhecidos. Essa estrutura pode ser considerada uma armação, com BF e BD atuando como membros de força dupla, enquanto EFG e EDC são membros de força múltipla.

Um diagrama de corpo livre para o membro EFG é considerado. A força inclinada FBF pode ser resolvida em componentes vertical e horizontal. A condição de equilíbrio de momento é aplicada na junta E.



<img alt="Equation 1" src="/files/ftp_upload/14292/14292_PT_Equation_1v2.svg" style="text-align: center; height: 15px;" />



A força FBF é calculada como 1.546 kN. Em seguida, a condição de equilíbrio de força horizontal é aplicada na junta E.



<img alt="Equation 2" src="/files/ftp_upload/14292/14292_PT_Equation_2v2.svg" style="text-align: center; height: 15px;" />



Substituindo o valor da componente horizontal de FBF na equação de equilíbrio, a força de reação horizontal em E é calculada como 0.375 kN. Da mesma forma, a condição de equilíbrio de força vertical é aplicada.



<img alt="Equation 3" src="/files/ftp_upload/14292/14292_PT_Equation_3v2.svg" style="text-align: center; height: 15px;" />



A força de reação vertical calculada na junta E é de 0.500 kN.

Agora, um diagrama de corpo livre para o membro EDC é considerado. As componentes horizontal e vertical de FBD podem ser expressas usando um triângulo de inclinação. A condição de equilíbrio do momento no ponto C é aplicada.



<img alt="Equation 4" src="/files/ftp_upload/14292/14292_PT_Equation_4v2.svg" style="text-align: center; height: 15px;" />



A força FBD é calculada como 1.677 kN.

Armações: Resolução de Problemas II

Considere uma talha hidráulica que suporte uma carga de 1 kN. Assumindo uma representação esquemática simplificada desta estrutura de pórtico, a força que atua sobre BD e ...

Education

JoVE Core

Mechanical Engineering

Engenharia Mecânica

Unit 1

Unidade 1

Structural Analysis

Análise Estrutural

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

Frames: Problem Solving II

hydraulic hoist force analysis

Hydraulic hoist force analysis shows how to find the forces in key members of a simple frame. The load is 1 kN, and the structure is represented with known member dimensions. In this setup, BF and BD act as two-force members. EFG and EDC are multi-force members, so each one is analyzed with a free-body diagram.

The first step is to study member EFG. The inclined force in BF is split into vertical and horizontal parts. Then the moment equilibrium condition is applied at joint E. Using this step, the force in BF is found to be 1.546 kN.

Next, the horizontal force equilibrium at joint E is used. The horizontal part of the BF force is substituted into the equation. This gives the horizontal reaction force at E as 0.375 kN. The vertical force equilibrium at the same joint is also applied. The vertical reaction force at E is calculated as 0.500 kN.

A free-body diagram for member EDC is then considered. The horizontal and vertical parts of FBD are written using a slope triangle. Finally, the moment equilibrium condition at point C is applied. This calculation gives the force in BD as 1.677 kN.

Hydraulic Hoist Force Analysis

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frames: problem solving ii

Hydraulic hoist force analysis shows how to find the forces in key members of a simple frame. The load is 1 kN, and the structure is represented with known member dimensions. In this setup, BF and BD act as two-force members. EFG and EDC are multi-force members, so each one is analyzed with a free-body diagram. The first step is to study member EFG. The inclined force in BF is split into vertical and horizontal parts. Then the moment equilibrium condition is applied at joint E. Using this...

machines

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key terms and concepts

Analyze a hydraulic hoist frame with free-body diagrams, equilibrium equations, and two-force members to find forces in BF, BD, and reactions at E.

Hydraulic Hoist Force Analysis | JoVE K12

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Hydraulic Hoist Force Analysis

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