How do I design a spring given only pressure and the the maximum length by which it can be compressed. I tried using the formula P=F/A but I don't have the force to be applied on that spring.
Pressure on the whole spring? From what I remember, springs carry torsional loads and bending loads. You can start by converting the given pressure into these. Then find a suitable diameter.
I've been trying to convert the pressure to force but I couldn't.The only given quantities are the spring pressure and the maximum length by which it can be compressed. Not given the spring material.
Any spring manufacture will have tables of spring materials and their rate per unit of deflection. From there you can decide what material to use and then the overall size of the spring. The length will usually be the last item to be arrived at based on the available room. You can go other ways but this is usually the simplest approach.