developments
products &
July 2011 Tube ProducTs InTernaTIonal
29
ASTM A 790 duplex pipes
Butting, Germany, has expanded its
components store in Knesebeck to
include ASTM A790 duplex stainless
steel pipes, in order to offer customers
quicker coverage of their needs at short
notice.
The pipes, in material 1.4462/UNS
S31803/UNS S32205 and based on
ASTM A790, are in store in sizes from
OD 219.10 to 406.40mm, with wall
thicknesses from 3.76 to 9.53mm.
In addition, the components store
continues to stock ASTM A928 duplex
pipes in sizes OD 33.7 to 323.9mm. For
larger projects and individual needs,
Butting can also produce ASTM A790
pipes in other project-specific sizes.
The use of duplex steel is suitable due
to its high level of corrosion resistance,
in particular stress corrosion cracking,
greater robustness and higher stretch
limits.
ASTM A790 covers in general the basics
and the requirements for manufacturing
seamless and welded steel pipes.
With regard to duplex materials, it
requires a welding procedure without
filler metal, which Butting implements
in its manufacturing technology.
In accordance with the standard, all
destructive tests (including hardness,
tension, flattening and bending tests)
and non-destructive tests (eg water
pressure and eddy current test) are
carried out on the pipes. The producer
supplies pipes with acid-cleaned and
passivated surfaces, above and beyond
the requirements of ASTM A790.
H butting GmbH & co KG
– Germany
Super-size, superalloy tube extrusions for USC
power production
Members of PCC Energy Group are
producing some of the largest superalloy
tubular products ever manufactured.
Wyman Gordon Forgings, Houston,
Texas, has extruded the huge tubes
specifically for headers for the next
generation of advanced ultra super
critical (A-USC) coal-fired power boilers.
Inconel 617 and 740 tubes, with 15"
diameter, 3.5" wall and 34ft length, are
produced on a 35,000-ton vertical press.
It is considered a major technology
advancement for USC development
programmes in North America, Europe
and Asia.
The ingots for extrusion were vacuum-
induction melted and re-melted at
Special Metals Corporation mill at
Huntington, West Virginia, where both
alloys were developed. While alloy
617 is a well-established solid solution
alloy, offering high strength and heat
resistance for extreme conditions at
highly elevated temperatures, alloy
740 is a precipitation-hardenable alloy,
specifically designed for the rigours of
USC service.
Thesesuper-size, superalloy tubeswill be
tested by many organisations worldwide
for application in various A-USC
programmes. Prior to production of the
tubes in Houston, a large Nimonic alloy
263 tube was extruded at the Wyman
Gordon mill in Livingston, Scotland.
Alloy 263 is another superalloy that may
find application in A-USC designs. The
ingot for manufacture of that tube was
produced at Special Metals Wiggin Ltd,
in Hereford, England.
The development of A-USC power
technology is seen as a means of
reducing the world’s consumption
of coal, as the units are projected to
operate at steam temperatures of 700
to 760ºC, resulting in power production
efficiencies of 48% or higher.
This efficient operation has the added
effect of reducing pollution problems
associated with emission of fossil fuel
combustion products, such as carbon
dioxide, sulphur dioxide and oxides of
nitrogen.
Pcc energy Group
– USA
Butting has expanded its Knesebeck components store
