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Three Risky Storage Tank Jobs

Storage tanks, both above ground and underground, are containers that store an amazing amount of liquid. They look very innocent on the outside, but they need consistent maintenance and repairs, and proper assessment to function properly. Working in the tank industry is never without its risks. It takes a strong team to battle confined spaces, potential gas leaks, faulty equipment, and much more. But, there are some tasks that might be a little more dangerous than others.

According to Terry Files, Inspector at Koch Pipeline Company, L.P., these are some dangerous jobs in the tank industry:

1: Jacking a heavy floating roof
 
Jacking Roof
source
 
2: Hanging a shell course (or most anything else) with an inexperienced operator
 
Hanging Shell
Gregory Coppola
 
3: Jacking cone roof columns or center pole
 
Jacking Column
source
 

Reader Submissions:

Ted Webber from Advanced Tank mentioned another risky tank job: “Installing concrete ringwalls underneath existing tanks. Particularly tanks with floating roofs in them. Installing additional shell courses for increased product capacity, via jacking the tank and installing new courses underneath the existing shell.”

brian barney burke, a construction supervisor, added his comments: I worked for 20 years for Bahrain Petroleum Co on their Tank Repair Programme which had been running since 1975. I believe most repairs to any Tanks can be dangerous so the correct approach to each repair ie. Risk Assessment and Method Statement plus Kick Off meetings prior to work commencing is essential. For me the most dangerous part of Tank repairs is actually the taking out of service of the said tank and Gas Freeing is probably the most dangerous. We were gas freeing a small tank containing a floating roof using instrument air instead of the usual Air driven compressors to run the Shell Blowers and Eductors. Using instrument air did not require the 24hr manual monitoring of the Gas Freeing process, but Air driven compressors require 24hr man monitoring, obviously for safety reasons.
The Tank had been cleaned and accepted and the cleaning check-list signed off by all parties.
Long story short when we arrived the next morning the Floating Roof sat half on and half off on the top of the tank very dangerously positioned.
Investigation found that some Pyrophoric material inside one of the internal pipes had self ignited and blow the roof up to the top of the tank due to the Gas Freeing not being fully completed also damaging the shell and external staircase.
Moral of this story is Tank Cleaning needs to be fully checked especially inside appurtenances like pipes pontoon legs.

Edwin Carpio, a Tank Construction Superintendent at Esso Highlands Limited (ExxonMobil), sent in his comments for risky tank jobs:

1. LNG Tank Roof Air Raising – it may look easy, but simple miss calculation and poor supervision could damage the entire tank.
LNG Tank Roof Air
 
2. Tank PWHT – tank may collapse due to excessive heat input.
Tank PWHT
 
3. Transporting of tank form Fab Shop to Site – see photo.
Fab Shop to Site
 
4. Tank pressure testing – sorry no available photo. Many known instances wherein tank uprooted from concrete foundation and blown up to nearby structure due to excessive pressure.

Greg MacLean, an Oil-Field Services Consultant, had this to share: Don’t forget invisible dangers such as toxic and explosive vapours. Particularly high H2S concentrations, which also leads to the development of spontaneously combustible pyrophoric deposits.

If you know of a dangerous tank job, please email us at marketing@castagra.com, and we will add it to the list.
 

TNphoto Tatsuya Nakagawa
Tatsuya Nakagawa is the VP of Marketing and co-founder of Castagra Products, a storage tank and wastewater coatings manufacturing company that is highly acclaimed for its sustainable coatings, cold weather tank coating applications, and its durable frac tank coatings. Castagra is used by the world’s top oil and gas field services companies.