Tank Dismantling and Reconstruction

[gazakat]

We have a 7800 m3 tank, 24.4 m dia x 18.3 high, (80' x 60') conical self supporting roof, welded steel, 6 x strakes @ 8' high, 2 @ 6', thicknes start at bottom 0.612 " to 0.25" at top.
We want to cut tank in half (vertically ) to transport to new site.
Need: 1 : help/suggestions to figure out best way to cut, and support during cutting and then transporting - in halves.
2: API 653 does not clearly state if we should cut plates in their 'staggered' pattern, ie along current welds, or if it is permissible to cut one verticle line from top to bottom. only 6" from HAZ...
Your help - suggestions appreciated
Gary

 

[IFRs]

Check the Reconstruction section of API 653

10.4.2.1 Provisions shall be made during the reconstruction of a tank to ensure that weld spacing requirements of
Figure 9.1 are maintained. New vertical joints in adjacent shell courses, made in accordance with 10.3.3.1, shall not
be aligned but shall be offset from each other a minimum distance of 5t, where t is the plate thickness of the thicker
course at the point of the offset.

 

[MJCronin]

Check the tank history in the Pittsburgh metro area....

Asland Oil reconstructed a petrochemical tank was located near the river in 1988. I one of the coldest days of the winter, the tank ruptured spilling four million gallons of diesel into the Monongahela River near Pittsburgh. Oil Flowed over 200 Miles.

The failure was quick and catastropic. A massive wave of oil overflowed the bund

The Ashland company rep called it "an act of god" and stated that no one could predict the accident.

No one, of course, who did not read or understand API-650/620 and the fundamental concepts related to britle failure

The tank was reconstructed from a much older thak that Ashland owned . There was no hydrostatic testing of the rebuilt tank.

http://www.nytimes.com/1988/09/16/us/us-jury-charges-ashland-in-oil-spill-near-pittsburgh.html

http://nepis.epa.gov/Exe/ZyNET.exe/...ults page&MaximumPages=1&ZyEntry=1&SeekPage=x

 

[DLite30]

Yea, airplanes crash, boats sink, and oil wells blow out...so let's just sit at home.

I guarantee that accident was caused by welding in cold weather with no pre or post heat of the welded areas. Not because of "old steel".