Pressure Vessels not in Use Since 1981

[panchagnula]

Hai all,
I thank the moderators of the website for giving such a good platform.Comming to my question i have been assigned to a old pressure vessel/storage tank which is been not in use since 1982 and i have been assigned to determine its condition weather i can bring back that to use .I dont have nameplate or any design data regarding how can i determine its present condition.What are the suggestable tests i can do on the vessel.Its capacity is 50,000 barrels.

Please help me out.

 

[BoyTNDT99]

1)try to find some hardstamp on the vessel part, your may got material grade and related operating data.
2) calculation the min. required thk. for internal pressure and any mechanical load.
3)Do NDT on welding seam to determine the joint eff. of the vessel.
4)Determine the new operating condition and shall be proof test by hydrostatic test to determine integrity of vessel & welding seam.

Hope this roughly details can help you...

 

[DSB123]

BoyTNDT99,
I suggest your advice is not valid. You will not find a hardstamp on the vessel plates so you canno find ut the material grade. You might get a hard stamp on flanges giving the material grade but not the plates.
As for point 2) how can you calculate this without the material grade of the plates plus the allowable stress is required so you need grade and to what edition of the Code the unit was built to. Doing NDT on a welding seam will only tell you the integrity of that part of the weld you NDT. It will not tell you the Joint Efficiency for the whole vessel. The only valid piece is rcommending a hydrotest of the vessel however personally I would not touch it with a bargepole unless it wasfor use on a non-hazardous duty.

panchagnula,
Suggest you should get in touch with your insurers and discuss with them what they would want you to do.

 

[JLSeagull]

If the capacity is 50,000 barrels this must be a storage tank and not a pressure vessel.

 

[metengr]

If this is indeed a storage tank, I would follow API Standards for oil storage tanks and perform nondestructive testing (NDT), as required by this standard, and what your insurers of this equipment would require.

As a minimum, I would conduct wall thickness surveys of the floor and sidewall of the tank along with seam and gith weld inspections (surface NDT).

 

[BoyTNDT99]

DSB123,
1)If can not find any hardstamp, You known that some PE design code permit to assume the allowable stress of materials as low as 13000 psi, determine the tensile strength by hardness test or if serious, cutout some the vessel sample then test by mechanical testing, so you can use this for your calculation.

2)The joint E of weldment is safety factor concept, you can determine to do it safely.

3) Hydro-test will proof all the integrity of vessel.

As I recommend is based-on in-service concept (not new fabrication concept), especially when no vessel data available and actually it required a lots of assessment step that we can not typing all details to this...

All data shall treated as outline only.

panchagnula,
Consult in full details with the AI of inservice pressure equipment as available.

 

[MJCronin]

panch...

Pressure Vessels:

Smaller containers (typically with rounded ends)designed to operate above 15 psig

Storage tanks: Everything else

-MJC

 

[JohnGP]

This discussion is now getting complicated.

 

[zerosum]

As MJC implies, panchagnula needs to post enough information that forum responders can determine whether he is dealing with a tank or dealing with a vessel. Based on size, I would think an API 620 or API 650 type tank?

 

[chicopee]

DSB123, if it is an NB/ASME pressure vessel, you should find a stamping on the shell or head of the vessel. Then you can get a copy of the manufacturer's data from the National Board for the relevant information that Panchagula seeks.

 

[JohnGP]

I have to add my vote for it being a storage tank. I could be wrong of course, but we have some LPG bullets (which are pressure vessels), the size of which scares me, but they would each hold about 11,000 barrels at best. A 50,000 barrel vessel - wow!

The advice of metengr would be a good start.

 

[DSB123]

chicopee,
Do you think it will be an ASME pressure vessel at 50,000 barrels? Most probably will be a Tank so I still beleive it will not have stmping to ID the material.

 

[chicopee]

dsb123, I have seen unfired pressure vessels as small as shop air tanks with NB numbers.

 

[JohnBreen]

Organizing A Vessel, Tank, and Piping Inspection Program

Summary: The following article is a part of the National Board Technical Series. This article was originally published in the July 1991 National Board BULLETIN. (6 printed pages

http://www.nationalboard.org/Index.aspx?pageID=185

Regards, John

 

[JohnBreen]

http://www.nationalboard.org/PrintPage.aspx?pageID=185

 

[gr2vessels]

pancho,
You have had a nice finish to your post;- please help me!
Would you have the decency of coming back after a week to your post and give a sign that you appreciate these replies, perhaps thanking to the posters for the help given? After thanking the moderators for this magnificent platform, too many people like this poster are abusing the forum. Perhaps some sort of screening of membership should be put in place...
gr2vessels