This paper presents an experimental and a finite element analysis which are conducted to determine the allowable and failure pressures in unflawed valve housing (designation DN100 PN40). Extensive three-dimensional non-linear finite element analyses are performed to obtain the plastic limit, collapse and instability loads for the valve housing under internal pressure and to predict the burst pressure obtained by experimental tests. Finite element results show that the failure pressures obtained by the limit load analyses give conservative results, except those obtained by using the ultimate tensile stress as the flow stress. It is shown that the plastic collapse pressure results obtained by a real strain hardening material model agree well with the experimental results.