... The result has been a mouse-based system which allows the user to place icons at the location of "events" on the pipeline (spans, rock dumps, etc ), using the on-screen display of digitised sonar data (figure 1) This marking of events can be carried out on-line as the data is acquired, or off-line using DAT...

...~ne can be "la~d" along the profile to assess the number and length of spans, the stresses resultlng, and the potentlal remedial requirements In practice, a number of routes can be assessed and, using an algorithm to categorlse spans by length and clearance (as a measure of rectification requirements...

... rocess con t inues , mid-span d e f l e c t i o n s w i l l i n i t i a l l y be n e g l i g i b l e b u ~ , because d e f l e c t i o n i s a f o u r t h - o r d e r f u n c t i o n of unsupported l e n g t h , beyond a c e r t a i n l e n g t h , mid-span d e f l e c t i o n w i l l i n c r e a s e r...

... effective means of avoldlng unnecessary free span rectification work When assessing plpeline freespans, two aspects require to be considered separately First, the stresses occurring m the span as a result of ~ t s own welght and current drag require to be estimated Second, the susceptiblllty of the span...

... estlmate tenslon frequency span span length current veloclty frequency measurement natural frequency conservatlve assumptlon condltlon natural frequencle peak stress murray development engineering international ltd span frequency measurement free span PIPELINE FREESPAN...