Question: “How often and what are the procedures for retesting an ISO container. (Pressure and thickness)”
Tank Guru: Hazardous materials may only be carried in tank containers (ISO tanks) that have a valid, current 5-year or 2.5-year test certificate.
A 5-year periodic test is required 60 months after the date of the original hydrostatic test, or the most recent subsequent 5-year test. The scope of the test must include a hydrostatic pressure test at the tank’s full Test Pressure, usually 150% of the Maximum Allowable Working Pressure. It will also include a visual interior inspection of the tank barrel, and exterior inspection of the container to ensure structural integrity of the frame and safety items such as the catwalk. A bench test of the safety relief valve is required along with a final leakage test (after the water has been drained and the relief valve re-installed), to ensure satisfactory operation of all service valves and equipment. All of these tests are carried out under the witness of a surveyor/inspector for a third party agency or Class Society, which will issue the test certificate and stamp the new test date on the tank’s data plate.
A 5-year test is also required at any time when welding operations have been conducted on the shell.
At the midpoint between each 5-year test interval, a 2.5-year test is required 30 months after the most recent hydrostatic test. This will include the exact same scope of testing/inspection as the 5-year test, except that the tank will not be hydrostatically tested. Instead only the leakage test (pneumatic) is conducted at normal operating pressure. Again all testing is carried out under the witness of the third party surveyor, and after successful completion the data plate is stamped and a test certificate is issued by the Class Society or competent authority.
There are no specific requirements for checking the thickness of the tank shell. However, the thickness should be checked by using a UT meter whenever there is reason for concern that the thickness may have been compromised by corrosion, or repairs to the pitting such as excessive grinding, etc.
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A ISO tank container is repaired by replacing the inlet and outlet pipes
of the vaporizer. After this type of repair does the tank container requires inspection and certification as per IMDG Rules.
Thanks
B.Murali
Not sure what you are referring to as the vaporizer, but the short answer is YES if the piping is considered a pressure-retaining part of the vessel. Repairs involving pressure-retaining components should be inspected and pressure tested. Re-certification would depend on the nature of the repairs.
Are there any certified iso-tank testing companies in or near Qatar and if so do you have any contact information.
The best way to find qualified facilities for repair and testing abroad is to check the ITCO website (www.itco.be) and search under ‘members’ to find service providers in different parts of the world. I don’t see anybody in Qatar or the middle east, but several in India.
Excellent site.
Do I have to perform a 2.5 year test on a brand new tank manufactured in 2010, which is about 30 months old.
From my understanding, the first 2.5 year test on a tank is only required between the first 5 year test and the next.
Please advise.
From: Oletank
Yes, you need to perform a 2.5 year test when the tank is 2.5 years old. The CSC Safety Inspection is only required once the tank is 5 years old, but the periodic test on the vessel is not exempted.
Is it required to perform hydro test after grinding or buffing of the tank
A hydro is required at regular 5-year intervals or “…in all cases where cutting, burning or welding operations on the shell of the tank have been effected, a hydrostatic test to at least the original test pressure should be carried out.”
So while grinding and buffing create some heat, they do not fall under the definition of “hot work” above found in 49 CFR 178.270-13. So as long as you are not welding pits first, for instance, before grinding, then NO you would not need to hydro test after grinding and buffing.
Do the steam coils of the tanks gets tested during a 2.5 years test?
The regulations don’t specifically address this to my knowledge, but yes it is standard practice to test the steam system when testing the barrel. If the steam system is found to be leaking, then normally the steam caps would be welded into place (or cut off and blanked permanently) as an indication to future users that the system is inoperable.
How to do testing 2.5 Year test and 5 year test !