Measuring and testing – Blower – pump – and hydraulic equipment
Patent
1998-12-30
2000-05-16
Kwok, Helen C.
Measuring and testing
Blower, pump, and hydraulic equipment
73 172, 73 37, 623 2, 607119, G01M 1900, A61F 224
Patent
active
060620757
ABSTRACT:
A method and apparatus for proof testing an assembled mechanical heart valve prosthesis having a valve body and at least one movable occluder wherein at least one of the components has a surface of nonmetallic crystalline material, such as pyrocarbon, in which microcrack growth may occur. The assembled valve prosthesis is subjected to fluid loading with the occluder in the closed position so as to create omnidirectional pressure of at least 20 psig therewithin on the downstream side of the occluder. During fluid loading of the assembled valve, acoustic monitoring is carried out using a transducer to detect sounds that are indicative of crack nucleation and/or incremental crack extension, based upon a predetermined fail-pass criterion. Any valve prosthesis wherein sounds of a greater magnitude are detected is rejected.
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Ely John L.
Haubold Axel D.
Ritz Joseph P.
Kwok Helen C.
Medical Carbon Research Institute, LLC
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