Crack in plastic fuel oil tank.

[clairelen]

My 2500 litre single-skin plastic tank was installed by an Oftec engineer 12 years ago on a 5 inch thick concrete base, 2 feet longer and wider than the tank. On 9th March, following a refill, a 2 inch split appeared half way up the tank. I plugged it with a piece of soap, dried the area and applied black silage-bag tape. So far all is well, but I am planning to install a replacement bunded tank soon. This happening indicates that there are stresses in a plastic tank, which after seasonal heating and cooling, plus emptying and filling, can suddenly cause a split to appear. So it is better to buy a bunded tank at the start.

 

[muggles]

Yes, bunded tanks are always best practice.

 

[oilboffin]

12 years ago wasn't it law for a 2500ltr tank to be bunded.Bob

 

[clairelen]

In November 2006 I was advised by the installing Oftec engineer that in Pembrokeshire a 2500 litre domestic oil tank could be single skinned.

 

[ianmcd]

I would be getting it changed right away, if your tank splits and oil gets into the ground and e/h get wind of it you will be in serious financial difficulties.

https://www.cornishmutual.co.uk/why...oil-spill-highlight-risks-of-domestic-heating

 

[clairelen]

Yes, it could in theory develop further splits. I am ordering a bunded tank tomorrow, and engaging a workman to extend the concrete base for this larger tank.The main point of my initial note was to warn people that a plastic skin holds stress which may, sooner or later, with temperature and load cycling, relieve itself by splitting. Luckily mine performed correctly for twelve years, with fourteen fills. As a matter of general interest, has anyone suffered similar splits within a bunded tank?

 

[muggles]

Part of the issue is exposure to UV light combined with the stresses you describe I think. Bunded tanks are of course protected from UV on the oil-containing internal skin, and are protected from the stress of having oil in them on the external skin.

Steel tanks get over this issue of course, because they are much stronger, but do need painting occasionally

 

[clairelen]

Yes, I could hardly bare to keep my hand on the hot tank during a bright summer's day. Perhaps a sun-shade of trees would have helped. I guess that, in bunded tanks, the outer skin also provides extra mechanical support to the inner skin. I'll stick to plastic for now.

 

[oilboffin]

I love steel tanks.Bob

 

[lostinthelight]

https://naturalresources.wales/media/681287/osr-wales-faq-rt-pc-final-draft-v2-01022017.pdf