d. Inspection - After machining to final dimensions ultrasonic inspection is
required to insure proper bonding and absence of porosity.
required to insure proper bonding and absence of porosity.
The ultrasonic inspection techniques must meet the requirements of DOD 2183,
and the inspector must be certified as SNT-TC-1A, Level II (Society for Non-
Destructive Testing).
and the inspector must be certified as SNT-TC-1A, Level II (Society for Non-
Destructive Testing).
Generally the total area of unbonded babbitt is not permitted to exceed 10
percent of the total babbitted surface, and no single unbonded area is permitted
to exceed a dimension of 1 inch.
percent of the total babbitted surface, and no single unbonded area is permitted
to exceed a dimension of 1 inch.
No porosity is permitted.
REFERENCES
(1) Copyright 1986 Electric Power Research Institute, EPRI-4719, "Cavitation
Pitting Mitigation in Hydraulic Turbines, Volume 1: Guidelines and
Recommendations." Reprinted with permission. Pages 3-11 to 3-13.
Pitting Mitigation in Hydraulic Turbines, Volume 1: Guidelines and
Recommendations." Reprinted with permission. Pages 3-11 to 3-13.
(2) Electric Power Research Institute, Pages 4-1 to 4-59.
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