and other critical Land-Based Structures for qualification of welding
procedures. These tests results should include tensile and impact properties
of both weld metal and heat-affected base metal. A list of specific
applications where the material has been successfully used in stressed
applications should also be provided. Details such as quantities and
thickness of material used, welding processes used, inspection standards
used, manufacturer's name and location, location of the component in service
and length of service, pre-weld and post-weld heat treatments, if any, and
type of requirements and inspections required of the material supplier in the
material purchase specifications.
(6) Fatigue data, preferably data in the high strain low-cycle
range (below 10,000 cycles), which considers the effect of the environment
(e.g., seawater, air, O2, HeO2, fresh water, mercury).
(7) Basic process to be used in producing the material and the
electrodes if the fabrication process included welding as well as other
fasteners, if involved.
(8) Data over a sufficient time period to justify the adequacy of
the material with respect to general corrosion and to stress-corrosion
cracking in its intended environment (e.g., seawater, marine atmosphere air).
(9) Nondestructive test requirements to be applied to base material
and weld joint, as appropriate.
c.
CLASS 3, Materials whose properties are to be proven. Materials
and components for which definitive information and experience are not
available are considered in this class. The basis for testing and the
criteria for acceptance of new materials and components will not
automatically be the same as for those currently in use. The proof of
acceptability of the material or component and justification of the
acceptance criteria must be provided by the applicant, THIS MANUAL NEITHER
SPECIFIES ACCEPTANCE TESTS FOR NEW COMPONENTS OR MATERIALS NOR ARBITRARILY
DEFINES ALLOWABLE OPERATING PARAMETERS. For example, the applicant should
demonstrate the effect of defects, manufacturing tolerances, and production
variations upon the reliability of the material or component by appropriate
model and/or prototype testing in a simulated service environment. The
applicant must establish that the new material or component possesses at
least the same factor of safety as is provided by proven materials in a
similar application.
Examples of Class 3 structural materials are those which are generally
characterized by low ductility such as ultra-high-strength metals, solid
glass, glass-reinforced plastic, acrylic plastics and ceramic material.
For pressure vessels and other structural materials, as a minimum, the
applicant should submit the following information in justification of the use
of a Class 3 material:
(1) Material chemistry requirements.
(2) Material mechanical properties.
Previous Page
