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CAESAR II Users Guide
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CAESAR II
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CAESAR II Version
13

Specifies the bi-axial stress ratio for bends, tees, and joints. The bi-axial stress r is defined as:

where:

ssh(2:1) is the short-term hoop strength, under 2:1 stress conditions

ssa(0:1) is the short-term axial strength, under axial loading only

In the absence of data from the manufacturer, use the default values:


Fitting


Component

Short-term
Strength Bi-axial
Stress Ratio (r)*

Bends

  • Filament-wound unidirectional 90° and ± Q°

  • Filament-wound and hand-lay 1

  • 100% hand-lay

  • 0.45

  • 1.0

  • 1.9

Tees

  • Filament-wound and hand-lay 1

  • 1.0

Other Hand laminated

  • CSM/WR 1, 9

  • 1.9

Joints

  • Spigot/Socket Adhesive or Mechanical Connection

  • Threaded

  • Flange

  • Laminated

  • 1.0

  • 0.45

  • 1.0

  • 2.0

You can use a higher factor for r if justified by testing according to 6.2.6 ISO 14692-2-2002.

CAESAR II assumes that the bi-axial stress ratio r is 1.0 for tees according to ISO 14692.

CAESAR II displays a warning message in the Error Checker if the bi-axial stress ratio r is greater than 20 for bends or joints. You can ignore the warning message.

If a piping system has no joints or bends, the corresponding bi-axial stress ratio r should not be required. However, you must type a positive value (such as 1.0) for r to get rid of error messages.