AN INVESTIGATION OF THE INSTANTANEOUS AND CREEP BUCKLING OF INITIALLY OUT- OF-ROUND TUBES SUBJECTED TO EXTERNAL PRESSURE

Technical Report · Wed Jan 30 04:00:00 EST 1963

OSTI ID:4717465

Corum, J M

A method was developed for predicting the instantaneous and creep buckling characteristics of initially out-of-round tubes subjected to lateral external pressure. Both the critical pressure causing coliapse and the deformation of a tube at the instant of impending collapse may be determined by the method. Stress distributions represented by segments of the short-time stress-strain curve for the tube material were used to determine the instantaneous buckling characteristics. For creep building, approximate stress distributions derived from isochronous stressstrain curves were utilized, and the resulting collapse predictions were observed to become increasingly conservative with time. The method was used to predict the instantaneous and creep buckling characteristics of a series of 8.0-in.-OD type 304 stainless steel tubes that were collapsed at a temperature of 1200 deg F. Although the number of experimertal tests did not represent an adequate sample, the instantaneous collapse pressures agreed closely with the predicted values, and the time- dependent collapse test results substantinted the observation that the theoretical creep-collapse predictions become increasingly conservative with time. It was found that a small initial out-of-roundness significantly reduces the resistance of a tube to collapse. (auth)

• Research Organization: Oak Ridge National Lab., Tenn.
• DOE Contract Number: W-7405-ENG-26
• NSA Number: NSA-17-011192
• OSTI ID: 4717465
• Report Number(s): ORNL-3299
• Country of Publication: United States
• Language: English

Related Subjects

BUCKLING
CREEP
DEFECTS
DEFORMATION
DIAGRAMS
DISTRIBUTION
HIGH TEMPERATURE
MATERIALS TESTING
METALS, CERAMICS, AND OTHER MATERIALS
PRESSURE
STABILITY
STAINLESS STEELS
STRESSES
TUBES