A lot of drillers (probably more than half) use PVC casing for most of their domestic wells. It is inexpensive, reliable, never rusts and, used within limits, will make a lifetime well. However, PVC has one major drawback: It is not as strong as steel pipe. This means that setting depths are limited, and you can’t get too rough with it either. A good, clean hole helps.
Figuring out maximum setting depth is fairly straightforward. The strength of the material times the joint weight will give you the max theoretical setting depth. “Theoretical” is the key word. It’s not a good idea to set at maximum theoretical depths, in case you have to work a tight spot or stick it. Having a little “in your back pocket” is always a good idea. Part of the strength of any solid is called the modulus of elasticity. Within this range, a material can be bent, compressed or stretched, and return to its original shape. Beyond this limit, permanent deformation happens. Beyond that, the material fails catastrophically. With pipe, you can pull on it within limits and it will return to its original dimensions. Beyond that, it will take a permanent stretch and will be weakened or part. Imagine a rubber band. It will stretch many times and return, but over pull it and it will break. Pipe is the same.