3m Diameter Tank Flush clean out Door

[Legoman92]

Hi Everybody,

I'm designing a 3m dia, 3.5m high tank to API 650 and the client would like a 600mm Flush clean out door. The problem is if you follow the dimensions in Table 5.9a, the bottom reinforcing plate becomes like half the bottom plate and looks quite excessive and has already been questioned by a few people. Anyone got any experience with this? Or do you just have to bite the bullet and do it?

Lego

 

[HTURKAK]

The applicable clause should be J.3.6 Tank Connections and Appurtenances..
IMO, it would be absurd to have a 600mm Flush clean out door if the size of the tank 3m dia, 3.5m high.

I would go with roof hatch and the roof would be flat roof with stiffeners.

 

[MJCronin]

I have said it before, and I will say it again ...

I strongly advocate drug testing for clients and, when MBAs get involved in preliminary tank project scoping, there will be hell to pay ...

HTURKAK is right ...."it would be absurd to have a 600mm Flush clean out door if the size of the tank 3m dia, 3.5m high"

The highly-paid MBAs should have told the client this up-front .... but they didn't because they have a concentration in Finance, not engineering ....

My opinion only


MJCronin
Sr. Process Engineer

 

[r6155]

Look at API 12D.

Regards

 

[JStephen]

The excessive bottom plate is likely correct. Cutting it with an arc inside instead of straight across would make it seem more reasonable.
Consider just using a round manway instead.
Consider using an API-12F (not 12D) tank- but note that standard is for certain fixed tank dimensions.

 

[LittleInch]

I'm designing a 3m dia, 3.5m high tank to API 650

Why??

That's an absurd specification to make a tank to that only 3m diam.

There are many other tank specs or just tanks designed by the vendor that would make much more sense.

That's only 24m3 total volume. just buy a 30' x 9' horizontal cylindrical tank

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[JStephen]

Just looking at this a bit.
The width of the repad is 1830 mm, distance to first vert adds 300mm each side, plus another 150mm each side, so 2730mm.
However, this is the arc dimension, not a linear dimension, so it equates to 104.3 degrees, or less than a third of the bottom perimeter.
Also see A.8.2 which would potentially let you eliminate the two verts on either side. It's not clear how Fig. 5.12 would be interpreted in that case.

 

[Legoman92]

I agree with the sentiment here. The reason it needs to be API compliant is that this tank is for a gold plant and hence needs to be meet the Cyanide code as there is small amounts of cyanide in this tank. The tank will also be stainless. I'm going to highly recommend a manhole instead of a clean out door.

Thanks for your thoughts.