UFC 4-390-01
23 July 2003
The applicant should justify the adequacy of the proposed
material and its application. The less information and
experience available regarding a proposed material or component
for a particular application, the greater is the burden of proof
for the acceptability of the material. This burden of proof is
the responsibility of the applicant.
A.2
CATEGORY 1 - MATERIALS AND COMPONENTS
To be classified as a Category 1 material, the material must be
manufactured to a commonly used commercial or federal
specification. Additionally, extensive experience in fabrication
of the specific component configuration (e.g., commercial off-
the-shelf) and a history of operation in a specific environment
must be presented to the SCA. For piping systems, compatibility
with both the specific internal and external fluids/gases to
which the piping will be exposed must be proven by previous
usage.
Unusual configurations or applications of these materials and/or
components with no documented history of use in the specific
environment might, however, place them in Category 2.
All view ports made of acrylic plastic should comply with the
requirements of ASME PVHO-1. View port materials other than
acrylic plastic will be considered Category 3 materials
A.3
CATEGORY 2 - MATERIALS AND COMPONENTS
Materials manufactured to a recognized commercial or federal
standard, but with no documented history of use in the specific
pressure vessel environment, fall into this category. Materials
used in standard commercial (or military) applications that are
not commercial off-the-shelf are also in this category. The use
of Category 2 materials and components requires justification by
complete design analysis of material properties and operating
stresses. Approval of a material or component for use in a
specific application will be based on the supporting technical
information provided by the applicant.
A.3.1 Structural Materials. For pressure vessels and hard
structure, the applicant should submit information on material in
accordance with Appendix B. For other structural components
(i.e., foundations, weight handling strength members, etc.,) the
applicant should submit the following information as
justification for the use of each Category 2 material or
component:
a)
The commercial or federal specification and the
chemical and physical properties of the base material in the
condition it will be used. If the material is to be welded,
brazed, cold worked, work hardened, etc., the acceptable material
properties at the completion of fabrication should also be
specified.
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