How are the stresses on a rail calculated for mounting components in a rack?

[jayachandra]

I want to know how the designing of a rail( Basically a long metal strip with holes at regular intervals to mount components). The rail is used either side of a rack to mount components.
So the problem is there are two rails separated by 19". The height of the rail is 40". At a height of 30" from the bottom a component of some weight is mounted on to the rail( By fastening the component to the holes in the rail. The rail is fixed at both top and bottom).
I hope someone is getting this ( Its difficult to explain without figures). I want to know how the load of the component will be acting on the rail at the fastened positions and how the stresses are calculated for the rail to wistand the load.

 

[Navin A S]

The load of the component will be acting on the rail in two ways: shear force and bending moment. The shear force is the force that acts parallel to the rail, while the bending moment is the force that acts perpendicular to the rail. To calculate the stresses on the rail, you need to first calculate the shear force and bending moment at the fastened positions. You can do this by using beam equations to calculate the reaction forces at the top and bottom of the rail due to the weight of the component. Then, you can use these reaction forces to calculate the shear force and bending moment at the fastened positions. Once you have calculated the shear force and bending moment, you can then use the equations for shear stress and bending stress to calculate the stresses on the rail. Shear stress is calculated by dividing the shear force by the cross-sectional area of the rail, while bending stress is calculated by taking the bending moment and dividing it by the second moment of inertia of the rail. You should also consider the fact that the rail is likely to experience fatigue due to repeated use and loading, so you may want to factor this into the design of the rail as well.