(3) Impact and fracture toughness properties over a range of
temperatures sufficient to define fully the fracture characteristics of the
material for the intended service environment. The material's fracture
toughness properties in a marine environment should be adequate for its
(4) Proof of weldability and fabricability, if fabrication process
includes welding, and qualification of welding procedures will be required.
Justification of Class 3 Materials. Submit at least the following
information to justify the use of a Class 3 material in a hazard category I
or II system.
Material chemistry requirements.
Material mechanical properties.
(3) Basic process to be used in producing the material.
Sufficient information is required to demonstrate that the procedures insure that
repeatable properties are obtainable by the process used.
(4) Resistance to shock loading, such as might be produced by
accidental blows on the system while pressurized.
(5) Effect of flaws, such as cracks or other discontinuities, on
Effect of temperature on material performance and notch
(7) Results of tests-to-destruction of samples fabricated from
the materials, and comparison of these results with the design basis predictions
of the failure point.
(8) Wet or dry fatigue data in the high-strain, low-cycle range
(less than 10,000 cycles) in environments; for instance, sea spray, air,
helium-oxygen, water immersion, etc.
(9) Data, covering an extended time period, justifying the
stress-corrosion cracking in a marine atmosphere in the presence of notches,
assuming the material is exposed to this type of environment.
repeatability of results.
(11) Nondestructive test requirements to be applied to the base
material and joints as appropriate.
(12) Hazards involved in fabrication or use of material with
respect to toxicity or flammability.
MATERIALS SPECIFICALLY NOT PERMITTED, The following materials are not
permitted for pressure vessel piping system fabrication: