Flange Retention Methods for Type F and FC Diaphragms
Swaged Lip—Lending
itself to high volume/low cost, the swaged lip resembles
the crimp ring in design except that the lip is an integral
part of the cylinder or bonnet. Lip should be flexible
and thin to insure proper flange retention.
Crimped Ring—This
method lends itself to high volume and low cost manufacture.
It utilizes a separate metal crimp ring and is assembled
to the unit with special crimping tools. These crimp rings
are made of thin, ductile materials so that the force
required to form the lip will not overcompress the diaphragm
flange area.
Flange Retention Methods for Type D and DC Diaphragms
Pivoted Rocking
Bracket—This method provides quick assembly and
disassembly. The pivoted rocking bracket is attached to
the housing flange, and the central jam screw secures
the bonnet against the mating flange.
Ring Clamp—“V”
style clamp rings can be disassembled quickly by removing
a clamp lever. A retainer plate is removed by turning
it 90 degrees where two “wings” and a retaining
screw drop into a keyhole.
Beveled Edge
Retainer Plate—Eliminates the need for
flange bolts as a beveled edge ring is snapped into a
groove in the extension of the cylinder housing flange.
This loads the bonnet assembly onto the mating bead, generally
producing low clamping forces.
Flange Retention Methods for Type O and OA Diaphragms
Crimped Ring—Used
in high volume, low cost applications, this method eliminates
typical flange construction and flange bolts.
Bezel Ring—This
common method provides minimum clearance of the housing
outside diameter. Male threads are machined on the cast
bonnet to utilize drawn sheet metal cylinder housings,
reducing costs.
Grooved Bonnet—This
method requires a sufficient number of circumferential
clamp bolts so distortion does not occur between flange
bolts. It is advisable to make provisions for the bead
groove in the cast or molded bonnet.
