P
arr reactors are normally
made of Type 316 Stainless
Steel, but they can also be made
of other alloys as well. The list of
available construction materials
includes:
Type 316/316L Stainless Steel
Alloy 20
C1018 Carbon Steel
Alloy 400
Alloy 600
Titanium Grades 2, 4 & 7
Nickel 200
Alloy B-2
Alloy C-276
Zirconium 702 & 705
Alloy Designation
Parr now uses alloy designa-
tion numbers to identify the
various corrosion resistant
alloys available for use in Parr
reactors and pres-
sure vessels. These
alloys can also be
identified by trade
names and by
ASTM, ASME, DIN
and other specifica-
tion numbers.
Many of the high
nickel alloys were
originally patented
and sold under
trade names, such
as Monel
1
, Inconel
1
,
Incoloy
1
, Carpenter
Alloy
2
, Hastelloy
3
,
etc. Most of the
original patents
have expired and
these alloys are now materials of
construction available from other
reputable suppliers, as well as
from the owners of the original
trade names.
Among the many corrosion
resistant alloys now available,
there may be two or three with
very similar compositions and
intended for use in the same
corrosive environment. In these
cases, Parr will select and offer
the most widely used alloy in
each of the basic corrosion
resistance categories, rather than
catalog and stock all three.
Each of these alloys has its
own physical strength and tem-
perature characteristics as well
as its own unique resistance to
certain corrosive materials. All of
these factors must be considered
when making a selection, with
cost and availability also becom-
ing factors in the final choice.
The basic composition of
these alloys
is listed in Table I.
Corrosion resistance information
can be obtained from various
corrosion handbooks and metal-
lurgical publications. Helpful
information can also be obtained
from the individual alloy
manufacturers.
Any abridged listing of corro-
sion resistance of various metals
and alloys can be potentially
misleading since it can not pos-
sibly deal with all of
the effects of concen-
tration, temperature,
pressure and the
presence of additional
ions, all of which have
a significant effect
upon the ability of a
reactor to withstand
corrosion. In addition,
the vulnerability of
any material to stress
corrosion cracking,
intergranular corrosion
and pitting must also
be considered when
judging the suitability
of a material for a par-
ticular application.
The principal characteristics of
the several construction materials
offered by Parr are summarized
on the following pages. These
listings are intended to serve only
as a starting point for any study
of comparative corrosion resis-
tance and physical properties.
Material manufacturers booklets
on each alloy are available on our
website at
.
Additional details may also be
obtained from other sources.
CSA Certification
Where appropriate, Parr
reactors are manufactured and
certified to the electrical code
established by the Canadian
Standards Association.
Identification of those units for
which CSA Certification has been
received will be provided upon
request. The CSA logo is shown
on the nameplate of each CSA
certified unit.
CE Certification
Where appropriate, Parr
reactors will carry the CE Mark
certifying compliance with all
applicable European Community
Directives.
Other National or
Local Codes
Parr regularly works with
other national, state or inter-
national authorities to obtain
individual approval for specific
vessels. Parr has obtained
Pattern Approval for pressure
vessels in China and CRN
Approval for pressure vessels
in all Canadian provinces. The
internationally recognized Quality
Assurance Program in place at
Parr and the experience of the
Parr engineering department in
working with these authorities
makes it possible to obtain these
approvals with little difficulty.
It is the user’s responsibility
to identify any such applicable
code so that these requirements
can be met before the vessel
is fabricated and delivered.
Parr’s network of international
distributors are familiar with the
applicable codes for pressure
vessels within their countries of
responsibility.
The Parr Instrument
Company will attempt
to answer questions
regarding corrosion
resistance and will
suggest materials
that might be suitable
for specific applications,
but no guarantee can
be made that any
particular alloy will
be fully resistant to
a prescribed set
of corrosive
conditions.
1
MONEL, INCONEL and INCOLOY are Registered Trademarks of Special Metals Corp.
2
CARPENTER 20 is a Registered Trademark of Carpenter Technology Corporation.
3
HASTELLOY is a Registered Trademark of Haynes International, Inc.
10
P a r r I n s t r u m e n t C o m p a n y
Materials of Construction
Certification, continued
