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Title: Evaluating All-Metal Valves for Use in a Tritium Environment

Abstract

In the tritium gas processing system, it is desired to minimize polymer components due to their degradation from tritium exposure (beta decay). One source of polymers in the tritium process is valve components. A vendor has been identified that manufactures a valve that is marketed as being made from all-metal construction. This manufacturer, Ham-Let Group, manufactures a diaphragm valve (3LE series) that claims to be made entirely of metal. SRNL procured twelve (12) Ham-Let diaphragm valves for characterization and evaluation. The characterization tests include identification of the maximum pressure of these valves by performing pressure and burst tests. Leak tests were performed to ensure the valves do not exceed the acceptable leak rate for tritium service. These valves were then cycled in a nitrogen gas and/or vacuum environment to ensure they would be durable in a process environment. They were subsequently leak tested per ASTM protocol to ensure that the valves maintained their leak tight integrity. A detailed material analysis was also conducted to determine hydrogen and tritium compatibility.

Authors:
 [1];  [1]
  1. Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
Publication Date:
Research Org.:
Savannah River Site (SRS), Aiken, SC (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1395965
Report Number(s):
SRNL-STI-2017-00516
TRN: US1800068
DOE Contract Number:
AC09-08SR22470
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; TRITIUM; VALVES; METALS; POLYMERS

Citation Formats

Houk, L., and Payton, A. Evaluating All-Metal Valves for Use in a Tritium Environment. United States: N. p., 2017. Web. doi:10.2172/1395965.
Houk, L., & Payton, A. Evaluating All-Metal Valves for Use in a Tritium Environment. United States. doi:10.2172/1395965.
Houk, L., and Payton, A. 2017. "Evaluating All-Metal Valves for Use in a Tritium Environment". United States. doi:10.2172/1395965. https://www.osti.gov/servlets/purl/1395965.
@article{osti_1395965,
title = {Evaluating All-Metal Valves for Use in a Tritium Environment},
author = {Houk, L. and Payton, A.},
abstractNote = {In the tritium gas processing system, it is desired to minimize polymer components due to their degradation from tritium exposure (beta decay). One source of polymers in the tritium process is valve components. A vendor has been identified that manufactures a valve that is marketed as being made from all-metal construction. This manufacturer, Ham-Let Group, manufactures a diaphragm valve (3LE series) that claims to be made entirely of metal. SRNL procured twelve (12) Ham-Let diaphragm valves for characterization and evaluation. The characterization tests include identification of the maximum pressure of these valves by performing pressure and burst tests. Leak tests were performed to ensure the valves do not exceed the acceptable leak rate for tritium service. These valves were then cycled in a nitrogen gas and/or vacuum environment to ensure they would be durable in a process environment. They were subsequently leak tested per ASTM protocol to ensure that the valves maintained their leak tight integrity. A detailed material analysis was also conducted to determine hydrogen and tritium compatibility.},
doi = {10.2172/1395965},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 9
}

Technical Report:

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