Page 28 - Design Criteria.qxd

29 ® Welcome to the Next Generation of Sealing Technology
Style RIR Style CGI
Sizing Parameters for Spiral Wound Gaskets
Non-circular Spiral Wound Gaskets
Spiral wound gaskets can be fabricated in non-circular shapes within limitations. As a general rule, if the ratio of the major I.D. to
the minor I.D. exceeds 3 to 1, and should any of these sides approach a straight line, it may not be possible to manufacture a stable
spiral wound gasket. Our product requires a definite radius or curvature to give it inherent strength and stability and to prevent it from
springing apart. Any application requiring a non-circular gasket should be submitted to our Technical Department for review to deter-
mine the feasibility of producing a satisfactory gasket as early as possible in the design stage.
The comments above and on the previous page relating to availability of sizes and recommended clearances for proper sizing
of FLEXITALLIC gaskets are general in nature. Many applications will arise where the recommended clearances are impractical due
to space limitation on the flange. Frequently, clearances between gasket sealing member and grooves must be reduced in order to
effectively maintain a seal under operating conditions, particularly when the higher pressures are encountered. Under such circum-
stances, FLEXITALLIC engineers should be consulted prior to finalizing designs.
Raised Face Flat Face Male and Female Tongue and Groove
Style CG Style R*
Flat Face to Recess
Flange Face
Recommended
Gasket Style
For general duties
Recommended
Gasket Style
For high pressure/
temperature duty,
also for gaskets with
PTFE filler, corrosive
or fluctuating pres-
sure or temperature
service conditions.
Style CG
Style CGI
Style R* Style R*
*NOTE:
It is essential that Style R gaskets are fitted
with a compression stop. Without a correctly
dimensioned stop the gasket can easily be
over-compressed resulting in failure. To pro-
vide a compression stop the depth of the
tongue, groove or recess should be controlled
to provide optimum compressed gasket thick-
ness with metal to metal contact on the flange
faces (see table on Page 27).