Easy Access to
Pressure Vessels
Parr reactors and pres-
sure vessels are equipped
with a unique
split-ring cover
clamp which adds greatly to the
convenience of the equipment
and the ease with which it can
be handled. This is an exclusive
Parr design (see sidebar) which
allows easy access to a pressure
vessel without using a heavy
screw cap, cumbersome cover
clamps, or a wide flange for
moveable bolts. Instead, the
head is clamped to the cylinder
by either a Type 4140 steel or
a Type 316 Stainless Steel ring
which has been split into two
sections. These sections slide
into place from the sides without
interfering with any fittings
attached to the head.
Self-Sealing and
Cap Screw Designs
Parr split-ring cover clamps
are made in two styles. For
reactors and vessels in which a
self-sealing O-ring is used as the
main head seal, there are no cap
screws in the split-ring sections.
The vessel is closed by simply
sliding the two ring sections
into place and locking them with
either an encircling drop band
or with attached, quick-opening
latches. This convenient closure
can be used on most small and
mid-sized stirred reactors and
pressure vessels, provided the
intended operating temperature
does not exceed the allowable
working temperature limit for the
O-ring seal.
Split ring closures for reactors
with PTFE, flexible graphite,
metal or other contained, flat
gaskets have a set of cap screws
in the rings which must be tight-
ened to develop the compressive
force required to seal the gasket.
These split rings are locked
together with either a drop band,
special compression ring with a
retaining lip, or quick opening
latches.
With either style, the closure
parts come completely away
from the vessel so that the head
with all of its fittings can be lifted
from the cylinder or the cylinder
can be dropped away without
disrupting any attached fittings.
When cap screws are used, they
are simply tightened or loos-
ened, they are never completely
removed from the split ring or
drop band. This saves time both
in opening and closing the vessel
and in looking for lost parts.
We have all heard the story of the man who
resigned from the Patent Office around 1900
because he believed that everything that could
be invented already had been. That is not the
philosophy that has driven Parr Instrument
Company over its more than a century of
service to the chemical industry. The following
prediction first appeared in February 1930 in the
“Forward” of our bulletin describing our catalytic
hydrogenation apparatus.
“The greatest chemical discoveries are yet
to be made, untold numbers of which will result
from the new studies in catalysis and catalytic
reactors. These studies have already unearthed
a mine of information, but with a more exact
knowledge of catalytic processes, much more
will be learned in the future.”
We are delighted with the foresight of our
predecessors here at Parr and are dedicated
to continuing this outlook for the future as we
conduct our second century of service to our
friends and customers in this critical industry.
Split-Ring
U.S. Patent No.
2625296
Split-Ring with Cap Screws
for Moveable Vessels
Split-Ring with Cap Screws
for Fixed Head Vessels
Split-Ring for Self Sealing
O-ring Closures
16
P a r r I n s t r u m e n t C o m p a n y
Split Ring Closures
