Approval Date: December 30, 2006
Code Cases will remain available for use until annulled by the applicable Standards Committee.
Nickel-Chromium-Iron Alloy N06600 for
Inquiry: May nickel-chromium-iron Alloy UNS
N06600 seamless condenser and heat exchanger tubes,
seamless pipe and tubes, plate, sheet and strip, rod and
bar, conforming to the Specifications SB-163, SB-166,
SB-167, and SB-168, be used for water-wetted service in
Section I construction?
Reply: It is the opinion of the Committee that nickelchromium-
iron Alloy UNS N06600 conforming to the
Specifications SB-163, SB-166, SB-167, and SB-168 may
be used for water-wetted service in Code construction under
Section I provided:
a They meet the chemical analysis and the minimum
tensile requirements of the ASME specifications for the
b The maximum allowable stress values for the material
shall be those given in Table 1B of Section II, Part D.
c Welded fabrication shall conform to the applicable
requirements of Section I.
1 The procedure and performance qualifications
shall be conducted as prescribed in Section IX.
2 Welding shall be done by any welding process or
combination of processes capable of meeting the
3 The use of filler metal that will deposit weld metal
with nominally matching composition as the material
joined is recommended. When the Manufacturer is of
the opinion that a physically better joint can be made
by departure from these limits, filler metal of a different
composition may be used provided the strength of the
weld metal at the operating temperature is not appreciably
less than that of the high alloy material to be welded,
and the user is satisfied that its resistance to corrosion is
satisfactory for the intended service.
4 Where welding repair of a defect is required, this
shall be followed by reexamination as required in PW-11.
Where a defect is removed and welding repair is not necessary,
care shall be taken to contour the surface so as to
eliminate any sharp notches or corners. The contoured
surface shall then be reinspected by the same means originally
used for locating the defect to be sure it has been
d Heat treatment after forming or fabrication is
neither required nor prohibited.
e This Case number will be shown on the Data Report.
Warning: Last items in stock!
CAUTION: Austenitic alloys are subject to stress corrosion
cracking, intergranular attack, pitting, and crevice corrosion
when used in boiler applications in aqueous environments. Factors
that affect the susceptibility of these materials are applied
or residual stress, water chemistry and deposition of solids, and
material condition. Susceptibility to attack is enhanced when
the material is used in a sensitized condition, or with residual
cold work. Concentration of corrosive agents e.g., chlorides,
caustic, or reduced sulfur species can occur under deposits
formed on the surface of these materials, and can result in severe
underdeposit wastage or cracking. For successful operation
in water environments, careful attention must be paid to
continuous control of water chemistry.
The Committees function is to establish rules of safety, relating only to pressure integrity, governing the construction of boilers, pressure vessels, transport
tanks and nuclear components, and inservice inspection for pressure integrity of nuclear components and transport tanks, and to interpret these rules when
questions arise regarding their intent. This Code does not address other safety issues relating to the construction of boilers, pressure vessels, transport tanks
and nuclear components, and the inservice inspection of nuclear components and transport tanks. The user of the Code should refer to other pertinent codes,
standards, laws, regulations or other relevant documents.