Pipeline Failure Investigation Report - PHMSA - U.S. Department of ...

Final Report – 813 8385 1
Metallurgical Analysis of 24-Inch Houstonia 200 Service Failure at MP 21.6 (8/25/08)
Page 8
Table 3. Results of bacteria analysis performed on scale samples removed from the
external surfaces, at and away from the region of external corrosion.
Scale from Location A
Test Result
Bacteria
Concentration
Scale from Location B
Test Result
Bacteria
Concentration
Aerobic positive Very High positive Very High
Anaerobic positive Very High positive Very High
Acid-Producing positive Very High positive Very High
Sulfate-Reducing negative - negative -
Iron-Related negative - negative -
Bacteria Concentration Key:
Very Low
Low
Moderate
High
Very High
(1 – 9 bacteria per mL),
(10 – 99 bacteria per mL),
(100 – 999 bacteria per mL),
(1,000 – 9,999 bacteria per mL),
(10,000 – 99,999 bacteria per mL)
Table 4.
Results of tensile tests performed on transverse samples
from Pipe Segment C (D/S of failure joint).
Pipe Segment C
Yield Strength, ksi 51.8
Tensile Strength, ksi 71.5
Elongation in 2 inches, % 33.0
Reduction of Area, % 52.0
CC TECHNOLOGIES, INC.