Storage tank rim seal life-time - standards

[Indyvidual]

Hello,

I have a question, is there a condition in any tank standard that the rim seal or components like rubber must be replaced every X years?
I have searched standards like API 650, 653, RP 575 and there is only mention of possible replacement during service, but the only condition is that it "has to be good".
Are there any specific dates, periods for replacing such a seal?

Or, if there is no such condition, are there any conditions specifying work of NBR rubber in contact with petroleum vapors?

I've been looking for a concrete answer to these questions for a few days now and so far I haven't been able to find an answer.

I would appreciate your answers.

I.

 

[IFRs]

The tank standards do not include the information you are looking for. Generally the environmental regulations are where you will find inspection intervals and performance criteria. In the USA this is the Federa EPA (Environmental Protection Agency) and the State DEP (Department of Environmental Protection), usually the Air Quality division. Specific dates or periods for seal replacement would not make sense as each installation experieinces different exposures and activity.

 

[HTURKAK]

This is the copy and paste of relevant item in API 653 ;

(9.13.5 Deterioration of Seal Material Material deterioration results from wear and corrosion on metallic elements, and chemical and weather deterioration of seal fabric. The service life and inspection information shall be used to determine whether a change of material is warranted.)


There are too many variables for the service life of floating roof seals. Some of them; surface roughness , no. of cycles, temperature , quality of the seal , product stored, temperature.....

Just thinking; ten years could be ??

 

[Indyvidual]

I've heard from a few people about 10 years or so, but that's more from their experience than from any standards, I guess.
Anyway, maybe I can find something else in the environmental and evaporative losses standards.

Thanks for the replies.