Container Construction - std301320000043

DOE-STD-3013-2000

It should be noted that designation as a pressure vessel can arise simply because of

the need to contain the internal pressure generated by radioactive decay and by

operation at a temperature higher than that at which it was filled and sealed.

Beyond that, its function as the primary containment requires that it be able to

contain the pressures that might conceivably be generated by all credible processes.

Finally, it should be noted that the pressure estimates derived using the pressure

equation derived in Appendix B are considered to be highly conservative bounding

estimates. Current data indicate that it is unlikely that container pressures will

exceed 790 kPa (100 psig) under normal storage conditions during a 50-year

storage period. It should also be noted that the container atmosphere may include

appreciable percentages of hydrogen in the total gas at the time of opening, and

appropriate precautions should be taken.

A.6.2.2

Container Construction

1. Use of low-carbon stainless steels, such as 304 L and 316 L, is recommended with

316 L being preferable to 304 L because of its greater corrosion resistance. Both

materials are justified on the basis of extensive experience in this and similar types

of service. Stainless steels 301, 302, and 303 are not recommended due to their

relatively low concentrations of alloying additions. The use of higher alloyed

materials is probably beneficial to container failure resistance, but given the less

thorough analysis of these alloys in the literature, it may be prudent to avoid their

use at this time.

A recent report on corrosion [Kolman 1999] strongly recommends low carbon grades

of stainless steel to avoid sensitization to stress corrosion cracking (SCC). The report

also notes the importance of welding techniques that will not sensitize the steel to

SCC. More information from Kolman's report can be found in Section A.6.3.3.3 of

this appendix.

2. The Assessment Report [DOE 1994a, 1994c] describes radiolytic effects with

plastics, hydrogenous compounds, and organic materials during storage of

plutonium-bearing materials. Prolonged plutonium storage necessitates exclusion of

such materials from sealed containers because radiolysis and thermolysis of organic

material can produce combustible and corrosive gases and increase pressure within