Name: lifting tong force analysis
Uploaded: 2023-09-22T11:49:25.000Z
Duration: 1 min 30 s
Channel: JoVE

Considere una pinza de elevación que transporta una carga de 100 kg. Comprende secciones móviles DAF y CBG unidas entre sí con el miembro AB.
Suponiendo que la estructura es simétrica alrededor del punto E, ¿qué fuerza actúa sobre el miembro AB?
Se dibuja un diagrama de cuerpo libre que indica las fuerzas que actúan en el punto E.
La fuerza de tensión del cable equilibra el peso de la carga y actúa verticalmente hacia arriba.
ED y EC son miembros de dos fuerzas. Por lo tanto, las fuerzas FED y FEC se dirigen hacia las articulaciones D y C, respectivamente.
Estas fuerzas se resuelven en componentes horizontales y verticales, y la geometría de la estructura se aplica para determinar el ángulo entre el miembro ED y el componente de fuerza horizontal.
La aplicación de la condición de equilibrio de fuerzas a lo largo de la dirección horizontal asegura que FED sea igual a FEC.
De manera similar, la condición de equilibrio de fuerzas verticales produce la fuerza a lo largo del miembro ED.
Ahora, considere un diagrama de cuerpo libre para la sección DAF. La condición de equilibrio de momento se puede aplicar a la unión F. 
Sustituyendo todos los valores conocidos en la ecuación se obtiene la fuerza a lo largo de la barra AB.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice HallPppp 305.</li>
	<li>Cerveza, F.P.; Johnston, E.R.; Mazurek, D.F.; Cromwell, P.J. y Self, B.P. (2019). Mecánica vectorial para ingenieros: estática y dinámica. Nueva York: McGraw-Hill. págs. 348</li>
	<li>Meriam, J.L., Kraige, L.G., y Bolton, J.N. (2020). Ingeniería Mecánica \u2012 Estática. Hoboken, Nueva Jersey: John Wiley. págs. 200</li>
</ol>

No se han declarado conflictos de interés.

máquinas: resolución de problemas ii

Las máquinas son estructuras complejas que consisten en miembros móviles y conectados por pasadores de fuerzas múltiples que trabajan juntos para transmitir fuerzas. Considere una tenaza de elevación que lleva una carga de 100 kg. Está compuesta por las secciones móviles DAF y CBG unidas con el miembro AB. <img alt="Figure 1" src="/files/ftp_upload/14295/14295_PT_Fig_1v2.svg" style="text-align: center; height: 350px;"> Suponiendo que la estructura es simétrica en el punto E, se puede calcular la fuerza que actúa sobre el miembro AB. Primero, se considera un diagrama de cuerpo libre que indica las fuerzas que actúan en el punto E. El peso de la carga, que equivale a la masa multiplicada por la aceleración debido a la gravedad, se calcula como 981 N. La fuerza de tensión del cable equilibra el peso de la carga y actúa verticalmente hacia arriba. ED y EC son miembros de fuerza dual. Como resultado, las fuerzas FED y FEC están dirigidas hacia las articulaciones D y C, respectivamente. <img alt="Equation 1" src="/files/ftp_upload/14295/14295_PT_Equation_1v2.svg" style="text-align: center; height: 13px;"> <img alt="Equation 2" src="/files/ftp_upload/14295/14295_PT_Equation_2v2.svg" style="text-align: center; height: 13px;"> Luego, las fuerzas FED y FEC se descomponen en componentes horizontales y verticales. La geometría de la estructura puede calcular el ángulo entre el miembro ED y el componente de fuerza horizontal como 30.96 grados. Las condiciones de equilibrio de fuerzas se pueden aplicar a la articulación E. La aplicación de la condición de equilibrio de fuerzas a lo largo de la dirección horizontal asegura que FED sea igual a FEC. De manera similar, la condición de equilibrio de fuerzas verticales arroja la fuerza a lo largo del miembro ED como 953.46 N. Ahora se considera un diagrama de cuerpo libre para la sección DAF. Se puede aplicar la condición de equilibrio de momentos a la articulación F. <img alt="Equation 3" src="/files/ftp_upload/14295/14295_PT_Equation_3v2.svg" style="text-align: center; height: 13px;"> El resultado ofrece la fuerza a lo largo del miembro AB como 2423.76 N. Comprender las fuerzas que actúan sobre cada miembro en este sistema de tenazas de elevación es esencial para garantizar una operación segura y diseñar mecanismos de elevación eficientes. Al analizar las fuerzas y aplicar las condiciones de equilibrio, los ingenieros pueden optimizar la estructura y garantizar que pueda transportar cargas de manera segura bajo varias condiciones.

Máquinas: Resolución de problemas II

Las máquinas son estructuras complejas que constan de miembros móviles de múltiples fuerzas conectados por clavijas que trabajan juntos para transmitir fuerzas. Considere una pinza de elevación ...

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Machines: Problem Solving II

lifting tong force analysis

Lifting tong force analysis shows how forces move through a pin-connected machine. The structure uses movable sections DAF and CBG with member AB linking them together. Because these parts work as connected members, the load can be studied with equilibrium methods.

The example starts with a 100 kg load at point E. The load weight is found by multiplying mass by gravity, which gives 981 N. The cable tension acts upward and balances that weight. Since the structure is symmetrical at E, the forces on the two sides can be compared.

Members ED and EC are two-force members, so their forces act along the members toward joints D and C. Their forces are then split into horizontal and vertical parts. Using the geometry of the tong, the angle between member ED and the horizontal is 30.96 degrees. Force equilibrium at joint E shows that F ED equals F EC, and the vertical balance gives the force in member ED as 953.46 N.

After that, a free-body diagram for section DAF is used. The moment equilibrium condition is applied at joint F. This step gives the force in member AB as 2423.76 N. This kind of analysis helps engineers check the forces in each member so lifting systems can work safely and efficiently under load.

Lifting Tong Force Analysis

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machines: problem solving ii

Lifting tong force analysis shows how forces move through a pin-connected machine. The structure uses movable sections DAF and CBG with member AB linking them together. Because these parts work as connected members, the load can be studied with equilibrium methods. The example starts with a 100 kg load at point E. The load weight is found by multiplying mass by gravity, which gives 981 N. The cable tension acts upward and balances that weight. Since the structure is symmetrical at E, the...

key terms and concepts

Analyze a lifting tong with pin-connected members, symmetry, and equilibrium. See how force, tension, and moments determine the load on member AB.

Lifting Tong Force Analysis | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

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Lifting Tong Force Analysis

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