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Duque, Juan

Publications and source records attributed to Duque, Juan.

10 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Lifetime Extension of the Stainless-Steel Components of the SAVY-4000 Storage Container - 18572

Surveillance of vented, stainless-steel Hagan and SAVY-4000 storage containers with some plutonium materials have revealed evidence of corrosion inside the container. There are ∼3000 items stored in Hagan containers and ∼600 items currently stored in SAVY-4000 containers at TA-55. The Hagan is made of 304L steel while the SAVY is made of 316L and should be less susceptible to corrosion. Given the relatively thin body wall of these containers (nominally 0.762 millimeters), it is essential to understand the effects of corrosion on the lifetime of the containers to ensure worker safety. Studies are being conducted on both container types to determine the relative susceptibility of the two containers to corrosion. This paper will describe the potential cause of the corrosion, the extent of corrosion, the types of corrosion observed, along with the results of accelerating aging experiments. The combined results of the surveillance and lifetime extension studies will be used to predict the container lifetime. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Evaluating Corrosion Effects on the Stainless Steel Components of the SAVY-4000/Hagan Nuclear Material Storage Containers

Surveillance of vented, stainless-steel Hagan and SAVY-4000 storage containers with some plutonium materials has revealed evidence of corrosion inside the container. There are ~3000 items stored in Hagan containers and ~600 items currently stored in SAVY-4000 containers at TA -55. The Hagan is made of 304L steel, while the SAVY-4000 is made of 316L and should be less susceptible to corrosion. Given the relatively thin body wall of these containers (nominally 0.762 millimeters), it is essential to understand the effects of corrosion on the lifetime of the containers to ensure worker safety. Studies are being conducted on both container types to determine the relative susceptibility of the two containers to corrosion. This paper describes the potential cause of corrosion, the extent of corrosion, and types of corrosion observed, along with the results of accelerated aging experiments. The combined results of the surveillance and lifetime extension studies establish a technical basis for extending the design life of the stainless steel components of the SAVY-4000 container from 5 years to 15 years.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Surveillance and Monitoring Program Full-Scale Experiments to Evaluate the Potential for Corrosion in 3013 Containers

A set of six long-term, full-scale experiments were initiated to determine the type and extent of corrosion that occurs in 3013 containers packaged with chloride-bearing plutonium oxide materials. The materials were exposed to a high relative humidity environment representative of actual packaging conditions for the materials in storage. The materials were sealed in instrumented, inner 3013 containers with corrosion specimens designed to test the corrosiveness of the environment inside the containers under various conditions. This report focuses on initial loading conditions that are used to establish a baseline to show how the conditions change throughout the storage lifetime of the containers.

36 MATERIALS SCIENCE↗
DOE OSTI2017

M441.1-1 Site Update

Explore the source record for details and available documents.

Stone, Timothy Amos↗
DOE OSTI2017

Effects of Laser Etching on the Corrosion Susceptibility of SAVY 4000 and Hagan Containers

Since the late 1990’s, the Hagan container was used as the primary container for packaging of plutonium-bearing materials. The Hagan design consisted of a threaded closure, a Viton® ORing, a carbon-carbon filter, and a 304L stainless steel (SS) body. Over the years, Hagans have shown vulnerability in their design [1]. In 2008, The Department of Energy (DOE) issued DOE M 441.1-1, Nuclear Material Packaging Manual, which detailed an approach to obtain highconfidence in containers by including specific design requirements, material contents and an approach to determine life span from said contents, and surveillance techniques [2]. In response to both the vulnerability issues with the Hagan and DOE M 441.1-1, the SAVY 4000 container with its twist style closure, Viton® O-Ring, Fiberfrax-Gortex filter, and annealed 316L SS body, was designed as the replacement for Hagan containers, but only for a short term lifespan of 5 years [1]. However, both the Hagan and SAVY 4000 are being pushed to maintain a lifespan of 40 years. Therefore, proper confidence must be placed on each component of each container to last a minimum of 40 years. So far, the biggest concern found during surveillance of these containers is corrosion and the potential for failure by corrosion. One concern is that the containers fail due to stress corrosion cracking (SCC), especially around the weld between the collar and the body as welds leave residual stresses. One advantage the SAVY 4000 has is that the body is annealed, but its weld is still susceptible as it was welded after annealing [3, 4]. Moreover, 316L SS is known to have a higher pitting resistance (pits are a precursor to SCC and can also lead to extensive failure of the material), than 304L SS [4]. During recent surveillance activities, two SAVY 4000’s containing Solution Assay Instrument (SAI) solutions were opened. The SAI SAVY 4000’s contained plutonium (Pu) in 3M HCl solution in plastic volumetric flasks placed inside of polyethylene bags. Historically, a SAVY 4000 containing an SAI solution is packaged for 3 weeks, however, these particular containers were not reopened until 14 months later. When opened, brown-red corrosion product was found all over the inside of the container as shown in Figure 1.

36 MATERIALS SCIENCE↗