Techniques to make the Duplex Stainless Steel Fasteners the right way

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Techniques to make the Duplex Stainless Steel
Fasteners the right way.
Great Steel Metals
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Want to fight the challenges of corrosion? Use
Duplex and Super Duplex Grades of Stainless Steel
offered by Great Steel Metals that provides
superior corrosion resistance. It works even at
the time when 316 grade is not enough.
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 Duplex Stainless Steel Fasteners (SAF 2205 or
UNS S31803) or Super Duplex Stainless Steel
Fasteners (SAF 2507 or UNS S32750) has important
feature which includes its high level corrosion
resistance which makes it superior to 304 or 316
grade Stainless Steel.
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It is this feature of duplex stainless steel
which when combined with high mechanical strength
and ductility makes it a fit material for
different kinds of applications.
Most often, the 316 Grade Stainless Steel is
termed as Marine grade because it is ideal
for marine environments. it makes one of the most
robust allows which remains fit for high chloride
environments. It is used for fastening on yacks
deck and other such uses.
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And yes while it is often used and ideal for
marine environments such as There are many places
where fastener strength and integrity are
important and here comes the role of stainless
steel. if stainless fastener gets submerged in
sat water, duplex would be the minimum
requirement. A high degree of quality control is
required in this matter and it needs to be
ensured that the source is specialized in Duplex
fastener manufacture.
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Duplex Manufacturing Technologies In the
extremely careful temperature controlled
environment, Duplex
Fasteners are manufactured with forged heads and
rolled threads. They can also be CNC machined
from either the round or hex bar -however, in the
extreme circumstances too, they would be made
with the help of forged heads and rolled threads.
Also, it is a basic requirement for threads to be
rolled rather than machined for ensuring the
production of  smoother and stronger threads as
compared to the machined/CNC threads.
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With this process, the tread which comes out have
strong yield, high surface finish, extreme
hardness, as well as wear resistance. Temperature
control also remains important during the process
of Hot Forging the fastener head. Prolonged
exposure to critical temperature should be
avoided while heating Duplex otherwise it might
produce unwanted Nitrides and Carbides. It is
important to use the digital control equipment to
heat through this temperature zone. It is then
automatically removed from the heat source when
the temperature becomes maximum for forging.
The Duplex item is then laser marked to ensure
fasteners traceability through the supply chain.
One also needs to obtain Test Certificates.
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Duplex Applications where would you use Super
Duplex over Duplex? There are many applications
which find usage of Duplex steels. They include
piping systems and pumps as the process of good
erosion and abrasion resistance is employed in
their  techniques. Also, there are ), valves,
heat exchangers, Keel Bolts which find a wide
usage with certain items submerged in salt-water
as well as other equipment.
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Duplex comes with strong general corrosion
resistance and is superior to grade 316 in lot
many scenarios such as in giving resistance to
inter-granular, pitting and crevice
corrosion. Super Duplex has much more greater
pitting resistance. Overall, the inference is
that 316 is good while Duplex is great and Super
Duplex comes to be the best.
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The approx PRE pitting corrosion values for 304
and 316 Stainless Steel along with Duplex as well
as Super Duplex grades are as following 304
17-20 316 25-30 Duplex 30-38 Super Duplex
gt40
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Great Steel  Metals, the leading duplex flanges
manufacturer in India (????? ??????
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steel fasteners to meet the requirements of the
customers.
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