If you have a pressure related high stress and not bending related , then this can be solved by either reducing the pressure or by increasing the thickness, this cannot be solved by increasing supports. Pl. check the "stress extended" report to undestand if pressure induced axial stress was the problem or bending induced. My understanding is that you had bending related problem and not due to pressure .

Also pl. write your question in proper english and complete sentences , so that others can understand what you are saying.

Regards