7/28/2019 Unit 4 2010 Summary Turbine

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CONFIDENTIAL

APS FOUR CORNERS

UNIT 4 WINTER 2010 OVERHUAL SUMMARY TURBINE

1475E.SAMHOUSTONPKWYS.SUITE#100,PASADENA,TX.77503PH(281)8845160FX(281)4769454

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BOILER FEED PUMPS

The 14X16 expander and the 16 discharge piping coming off the north and south

boiler feed pumps have been inspected utilizing the 37 DLplus Panametrics thickness gauge.

These two components were check for thickness by establishing a 2 grid on the pipe surface.

UT thickness was collected at the grid points and recorded in a data table included in the report

following. The north 14X16 expander had an average UT thickness of 2.299 and the 16 pipe

had an average reading of 2.369 which is well above the minimum wall thickness 2.040. The

south boiler feed pump 14X 16 expander have an average UT thickness reading of 2.315 and

the 16 pipe of an average UT thickness reading of 2.385, both components wall thicknesses are

well above the minimum wall thickness of 2.040.

HIGH ENERGY PIPING

HOT REHEAT PIPING- A total of 4 girth welds have been inspected. The inspection

method used included Wet Fluorescent Magnetic Testing, (WFMT) inspection, UT Shear Wave

inspections, UT thickness inspection, and circumferential measurements on 4 welds. Prior to UT

shear wave inspection on the HEP, all welds were prepared buffed cleaned, WFMT inspected,

UT thickness inspected in four quadrants and circ. measured both up and downstream from the

weld. The welds included the following: FW-61, FW-81,(tee to pipe butt weld) FW-66, and

FW-87(elbow to pipe) located on the mezzanine deck inside the turbine building. No relevant

indications have been found.

MAIN STEAM PIPING- 13 girth welds have been inspected on the Main Steam piping

system. Several type of inspection method was utilized to inspect these welds: WFMT

inspection, UT thickness measurement in four quadrants, circumferential measurement upstream

and downstream from the weld where possible, and 100% UT Shear Wave. All girth welds were

power buffed cleaned free of scale material about 12 on each side of the weld. The following

girth welds have been inspected: matching speed valve connections weld located on the

mezzanine deck inside the turbine building, no relevant indication found; 4 each Main Steam

Stop Valve (MSSV) inlet piping welds, weld #s FW 1-13, FW 1-14, FW 2-13, FW 2-14, no

relevant indication found on all four welds; 4 each MSSV to Main Steam Control Valve

(MSCV), MSSV #1 to MSCV #1, MSSV#2 to MSCV #2, MSSV#3 to MSCV #4, MSSV #4 toMSCV #3; and 4 each MSCV outlet piping weld #s FW 1-15, FW 1-16, FW 2-15, and FW 2-16.

Several surface linear indications has been found on all 4 of the MSSV to MSCV girth welds,

they range from 3/16 to 3/8 in lengths, all indications have been grind out and re-inspected, no

relevant indications has been noted on the excavated areas. The excavation depth did not exceed

7/28/2019 Unit 4 2010 Summary Turbine

2/2

CONFIDENTIAL

APS FOUR CORNERS

UNIT 4 WINTER 2010 OVERHUAL SUMMARY TURBINE

1475E.SAMHOUSTONPKWYS.SUITE#100,PASADENA,TX.77503PH(281)8845160FX(281)4769454

PAGE2OF2

1/8 and no repairs were needed. No relevant indications were found on the MSCV outlet pipingweld #s FW 1-15 and FW 2-16. MSCV outlet piping weld # FW 1-16 had several linear

indications, 3/16 to 1\4 in length, all indications has been ground out and re-inspected. No

relevant indications were found and the excavation depth did not exceed 1/8, no repairs were

needed.

MSCV outlet piping weld # FW 2-15 have several linear indication at the toe of the weld,

during the initial inspection two 3/16 LI have been found on the bottom toe of weld and the

west side of the pipe and a 1 LI was found on the southwest of the pipe. These three linear

indications crack open and they connected during the freezing of the MSCV to replace the seats

inside the valve body. The 1 linear indication develop to a 6 crack and connected to the 3

1/16 indication, this linear indication have been ground out and re-inspected and no relevantindications has been found, excavation depth did not exceed 1/8. The two 3/16 linear

indication cracked open to a 7/8 depth and 4 in length. Samples have been cut out, sent to

the libratory to be analyzed. Another WFMT and UT shear wave inspection was performed

where the boat samples have been cut out prior to welding the excavation area and no relevant

indications have been found. Also 4 valve seat pin have been welded back on the control valve

during excavation repairs, these 4 welds and the repair weld have been dry MT inspected before

the post weld heat treatment. A final inspection on the excavation area and the 4 seat pins was

conducted by means WFMT and UT shear wave, no relevant indications has been found.