Figure shows an impression of one of many lifting arrangements produced and used at a steel fabrication workshop. It was manufactured to lift a maximum of 50 kg and due to a product line change, it needs to be modified to lift a maximum mass of 100 kg. Furthermore, the lifting mechanism at the loading point needs to be changed to a motor-driven winch which weighs 26kg. This motor driven win ch can accelerate a loads of 100 kg to 0.8 m/s2 in 1 second. Due to these changes, the factory manager needs to know whether the present lifting cranes can be modified as quickly as possible using only the left over pipes that had been purchased to manufacture thethe original lifting cranes. Your task is to provide the manager with a suitable proposal.
The required design constraints are as follows:
Function of the existing cranes:
A loading block is attached as shown to Pipe 3. The load will be raised from the floor level to a height of 1.5 metres. Do not consider the geometry of the load at this stage. Pipe 2 is not attached to the base plate and free to rotate inside Pipe 1. Do not consider the plate attachment to the floor, assume pipe 3 is welded to a perfectly rigid plate. Pipe 3 is rigidly connected to Pipe 2 by means of welding etc.
Available materials for modifications:
Materials: A few lengths of each of Pipe1, Pipe 2 and Pipe 3. (All pipes are steel with Ultimate Strength is 320 MPa, Yield Strength 280 MPa, Shear Strength 248 MPa, E= 200 GPa, Poisson's ratio =0.3, Density 7880 kg/m3)