<body><script type="text/javascript"> function setAttributeOnload(object, attribute, val) { if(window.addEventListener) { window.addEventListener('load', function(){ object[attribute] = val; }, false); } else { window.attachEvent('onload', function(){ object[attribute] = val; }); } } </script> <div id="navbar-iframe-container"></div> <script type="text/javascript" src="https://apis.google.com/js/plusone.js"></script> <script type="text/javascript"> gapi.load("gapi.iframes:gapi.iframes.style.bubble", function() { if (gapi.iframes && gapi.iframes.getContext) { gapi.iframes.getContext().openChild({ url: 'https://www.blogger.com/navbar.g?targetBlogID\x3d8968604820003269863\x26blogName\x3dChemical+%26+Process+Technology\x26publishMode\x3dPUBLISH_MODE_BLOGSPOT\x26navbarType\x3dBLUE\x26layoutType\x3dCLASSIC\x26searchRoot\x3dhttp://webwormcpt.blogspot.com/search\x26blogLocale\x3den\x26v\x3d2\x26homepageUrl\x3dhttp://webwormcpt.blogspot.com/\x26vt\x3d6402931565399164945', where: document.getElementById("navbar-iframe-container"), id: "navbar-iframe" }); } }); </script>

Chemical Process Technology

Continue to learn tips, knowledge and experience about Chemical Process Technology...

Enter your email address:


CLOSE WINDOW


 

Chemical & Process Technology

A place to share knowledge, lesson learnt...

Saturday, April 4, 2009

Display problem ? Click HERE

Recommended :
- Subscribe FREE - Processing Magazine
- Tips on Succession in FREE Subscription

Earlier discussion in "Acoustic Induced Vibration (AIV) Fatigue" has discussed the generation of high frequency acoustic excitation downstream of pressure reducing device and potential of downstream piping failure due to Acoustic Induced Vibration (AIV). Whenever there is pressure drop with mass passing through the valve, internal acoustic energy is generated and transmitted to downstream piping and potentially lead to severe piping excitation, vibration and stresses on downstream piping, in particular at discontinuity section i.e fabricated Tee, small bore connection, welded pipe and pipe support, etc. This acoustic excitation phenomena is generally involve high frequency (more than 1000Hz) acoustic energy. When high frequency acoustic energy is matches with mechanical natural frequency of piping and its component, excitation amplitude is at maximum and lead to increased stress level.

A piping segment may be excited in circumferential and longitudinal mode. Following image shows piping circumferential and longitudinal excitation patterns in different nodal arrangement.





The following image display acoustic excitation in 3D.



The following video clip shown a piping excitation in circumferential and lead to severe stress level at branch.





Related Topic

Labels: , ,

posted by Webworm, 3:07 PM

0 Comments:

Post a Comment

Let us know your opinion !!! You can use some HTML tags, such as  <b>, <i>, <a>

Subscribe to Post Comments [Atom]

Links to this post:

Create a Link

Home:

<< Home