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Re: Plumbness level alowed in storage tank as per api-650 designFrom: S.SHAHUL HAMEED 
Date: Saturday, February 26, 2011
Time: 4:15:15 AM
Remote Name: 220.127.116.11
Kindly refer API650 Clause 7.5.2 Plumbness
a. The maximum out-of-plumbness of the top of the shell relative to the bottom of the shell shall not exceed 1/200 of the total
The out-of-plumbness in one shell course shall not exceed the permissible variations for flatness and waviness as
specified in ASTM A 6M/A 6, ASTM A 20M/A 20, or ASTM A 480M/A 480, whichever is applicable.