13 - Length of Belt Connecting Two Pulleys

Problem
Two flat belt pulleys have a center to center distance of 137 cm, and diameters of 72 cm and 36 cm, respectively. Neglecting the sagging of belt...

  1. compute the length of belt if both pulleys will rotate in the same direction.
    A.   464.5 cm C.   446.0 cm
    B.   553.1 cm D.   535.4 cm
  2. compute the length of belt if the belt will be cross-connected to make the pulleys rotate in opposite directions.
    A.   654.1 cm C.   564.2 cm
    B.   465.2 cm D.   645.1 cm
  3. determine the distance of the point from the center of the bigger pulley where the belt will cross when cross-connected.
    A.   91.3 cm C.   89.4 cm
    B.   100.4 cm D.   98.7cm

 

Solution to Problem 505 | Flexure Formula Jhun Vert Tue, 04/21/2020 - 11:18 pm

Problem 505
A high strength steel band saw, 20 mm wide by 0.80 mm thick, runs over pulleys 600 mm in diameter. What maximum flexural stress is developed? What minimum diameter pulleys can be used without exceeding a flexural stress of 400 MPa? Assume E = 200 GPa.
 

Problem 352 | Equilibrium of Non-Concurrent Force System Jhun Vert Sun, 04/19/2020 - 11:55 am

Problem 352
A pulley 4 ft in diameter and supporting a load 200 lb is mounted at B on a horizontal beam as shown in Fig. P-352. The beam is supported by a hinge at A and rollers at C. Neglecting the weight of the beam, determine the reactions at A and C.
 

Pulley mounted at the midspan of simple beam

 

Problem 339 | Equilibrium of Parallel Force System Jhun Vert Sun, 04/19/2020 - 11:07 am

Problem 339
The differential chain hoist shown in Fig. P-339 consists of two concentric pulleys rigidly fastened together.
 

Differential Chain Hoist

 

The pulleys form two sprockets for an endless chain looped over them in two loops. In one loop is mounted a movable pulley supporting a load W. Neglecting friction, determine the maximum load W that can just be raised by a pull P supplied as shown.
 

247 - Resultant of couples in a 3-step pulley Jhun Vert Sat, 04/18/2020 - 01:54 pm

Problem 247
The three-step pulley shown in Fig. P-247 is subjected to the given couples. Compute the value of the resultant couple. Also determine the forces acting at the rim of the middle pulley that are required to balance the given system.
 

Couples on three-step pulley