Except when a fitting let's loose or the pipe splits with air you have an explosion as the entire volume of compressed gas decompresses outward into the lower pressure atmosphere. When a liquid decompresses you have the pressure put against the end of the column rapidly diissapate and the large volume of non-compressable liquid just splurts (splurt: kinda like slobbering). Broken pieces are not propelled away from the rupture like bullets.
On 4/4/07, Chris Brown <[EMAIL PROTECTED]> wrote:
PSI is PSI no matter what your dealing with. Thank you, Chris Brown Fire Protection Designer, Poole Fire Protection Office: 913.829.8650 Direct: 913.747.2056 Cell: 913.208.3600 Fax: 913.829.8690 -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Wednesday, April 04, 2007 3:33 PM To: [email protected] Subject: RE: Hydrostatic vs. Pneumatic Testing 200psi of air pressure is not the same as 200psi of water pressure due to the compressibility of air versus water. We never did more than 50psi for an air test for sensitive areas. If it passed the air test at 50# we never had any issues with the 200# water test. Craig L. Prahl, CET Fire Protection Group Mechanical Department CH2MHILL Lockwood Greene 1500 International Drive PO Box 491, Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 [EMAIL PROTECTED] http://www.lg.com -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Ray Schmid Sent: Wednesday, April 04, 2007 3:46 PM To: [email protected] Subject: Hydrostatic vs. Pneumatic Testing I have a client that needs to have a hydro performed for a modified PA system over a live data center and they are naturally concerned with conducting a traditional hydro above $500M worth of servers. The 40# air test has been successfully completed and they are questioning why a similar test with air at a higher pressure could not be done as an alternative to a hydro. Assuming a constant temperature throughout the test, why would a 200 psi test using air not be equivalent to the traditional hydro that uses water? It seems the requirement for a hydro is as old as piping itself, but all I can tell them at this point is that the standard requires a 200# test with water. Not a very technical justification. Are there tangible benefits to pressure testing the system with water that would not be realized with a pneumatic test? Ray Schmid, P.E. Principal Koffel Associates, Inc. 410-750-2246 www.koffel.com <http://www.koffel.com/> _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
-- Ron Greenman at home.... _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
