CG-47 CG-47
CG 47 CLASS ADVISORY NR 06-93
INTERIM FLUSHING PROCEDURES FOR PRAIRIE AND MASKER AIR COOLERS
REF/A/CON/AEGIS PROG MGR/13JAN93//
REF/B/DOC/INGALLS SHIPBLDG/-/-/NOTAL//
REF/C/DOC/NAVSEA/-//
REF/D/DOC/CDNSWC/-//
NARR/REF A IS BLEED AIR SYSTEM MEETING, ARLINGTON, VA. REF B IS
ACPY WORK SPECIFICATION 524-11-001 (CG 50 ONLY). REF C IS NSTM
CHAPTER 254, HEAT EXCHANGERS AND AIR COOLERS. REF D IS PMS MRC
5516/B9 W61R N, LU-1, AIR COOLERS.//
RMKS/1. THE PURPOSE OF THIS CLASS ADVISORY IS TO PROVIDE INTERIM
FRESH WATER FLUSHING PROCEDURES FOR THE PRAIRIE AND MASKER AIR
COOLERS IN ORDER TO IMPROVE BLEED AIR SYSTEM RELIABILITY.
2. BACKGROUND.
A. CG 47 CLASS BLEED AIR SYSTEMS HAVE EXPERIENCED A HISTORY
OF FAILED BLEED AIR VALVES. THE MAIN CAUSE OF VALVE FAILURE IS
SALT WATER INTRUSION INTO THE B/A SYSTEM.
B. THE B/A SYSTEMS HIGH OPERATING TEMPERATURE CAUSES A HARD
SCALE DEPOSIT TO FORM ON THE AIR SIDE OF THE COOLERS WHEN SEA
WATER ENTERS THE B/A SYSTEM THROUGH DETERIORATED PRAIRIE AND
MASKER AIR COOLERS. AS SCALE IS DEPOSITED THROUGH THE B/A
PIPING, IT CAN CONTAMINATE VALVES (APPROX 750) THROUGHOUT THE
SYSTEM. TO DECONTAMINATE THE SYSTEM, ALL OF THE CONTAMINATED
VALVES MUST BE OPENED/CLEANED AND THE ENTIRE PIPING SYSTEM
FLUSHED.
C. AS PER REF A, SEVERE CLOGGING OF COOLER TUBE BUNDLES HAS
CONTRIBUTED TO BOTH MICROBIOLOGICAL ATTACK AND EROSION OF THE
TUBE MATERIAL (90-10 CUNI). BOTH MECHANISMS ATTACK THE TUBE
ALLOYS PROTECTIVE OXIDE LAYER. TO COMBAT THIS PROBLEM, A FRESH
WATER FLUSH AND LAY UP OF THE PRAIRIE AND MASKER AIR COOLERS
SHALL BE INITIATED WHEN THE B/A SYSTEM IS TO BE SECURED FOR
GREATER THAN 72 HOURS. THIS WILL HELP REMOVE PARTICULATE MATTER
BEFORE IT CAN CLOG TUBES AND WILL HELP IN THE PREVENTION OF SCALE
BUILD UP.
D. AEGIS CRUISER PLANNING YARD IS DEVELOPING A MODIFICATION
SIMILAR TO REF B WORK SPEC, TO INSTALL FRESH WATER FILL AND DRAIN
FITTINGS ON EACH COOLER. IN ADDITION, THE MODIFICATION WILL
REPLACE THE CURRENT COOLER BUTTERFLY ISOLATION VALVES WITH NEW
ISOLATION BALL VALVES. THIS WILL ALLOW THE SHIP TO EFFECTIVELY
ISOLATE THE COOLERS FOR PREVENTIVE AND CORRECTIVE MAINTENANCE.
E. CDNSWC (9214) IS DEVELOPING A CG 47 B/A SYSTEM
FLUSHING/SOAK PROCEDURE FOR DECONTAMINATION OF THE B/A SYSTEM
IN THE EVENT OF SALT WATER INTRUSION. THIS PROCEDURE WILL BE A
MODIFICATION TO AN EXISTING DD 963 CLASS PROCEDURE.
F. NAVSEA 05Y3D AND 05X23 ARE INVESTIGATING A LONG TERM
RESOLUTION OF THE SALT WATER INTRUSION PROBLEM INCLUDING CHANGING
COOLER TUBE MATERIAL AND BLEED AIR VALVE UPGRADES.
3. ACTION. CG 47 CLASS SHIPS SHALL FRESH WATER FLUSH AND LAY UP
BOTH PRAIRIE AND MASKER AIR COOLERS WHEN THE BLEED AIR SYSTEM IS
TO BE SECURED FOR GREATER THAN 72 HOURS.
A. FOR SHIPS NOT EQUIPPED WITH COOLERS MODIFIED WITH
FILL/DRAIN VALVES, UTILIZE THE FOLLOWING INTERIM PROCEDURES TO
FLUSH THE PRAIRIE AND MASKER AIR COOLERS:
(1) SHIPS WITH CONSECO MANUFACTURED PRAIRIE/MASKER AIR
COOLERS AND THERMALXCHANGER PRAIRIE AIR COOLERS:
(A) ISOLATE AND TAG OUT THE COOLER IAW CURRENT
SHIPBOARD INSTRUCTIONS.
(B) REMOVE COOLER SEAWATER VENT AND DRAIN PLUGS.
(C) DRAIN SEAWATER SIDE OF COOLER TO THE BILGE AND
REINSTALL DRAIN PLUG. ENSURE WATER DOES NOT COME
INTO CONTACT WITH ELECTRICAL EQUIPMENT.
(D) FILL COOLER WITH FRESH WATER UNTIL WATER APPEARS AT
THE VENT: DRAIN AND REFILL.
(E) REINSTALL VENT PLUG.
(F) TAG IN COOLER LEAVING THE COOLER ISOLATION VALVES
IN THE SHUT POSITION UNTIL ALIGNING THE COOLER FOR
OPERATION.
(G) PLACE A CAUTION TAG ON THE COOLER ISOLATION VALVES
AND PACC GTM START PUSHBUTTONS AND EPCC GTG START
PUSHBUTTONS: QUOTE-PRAIRIE AND MASKER AIR COOLERS
ARE ISOLATED. ENSURE SEA WATER IS ALIGNED TO THE
COOLERS PRIOR TO B/A SYSTEM OPERATION. -UNQUOTE
(H) PERFORM THIS PROCEDURE EVERY TWO WEEKS WHILE IN
LAY-UP IAW REF C.
(2) DUE TO DESIGN AND MANPOWER CONSIDERATIONS, SHIPS WITH
THERMALXCHANGER MANUFACTURED MASKER AIR COOLERS SHALL PERFORM A
SALT WATER LAY-UP AS FOLLOWS:
(A) UPON SECURING FROM SEA, SHUT THE COOLER ISOLATION
VALVES.
(B) PLACE A CAUTION TAG ON THE COOLER ISOLATION VALVES
AND PACC GTM AND EPCC GTG START PUSHBUTTONS:
QUOTE-MASKER COOLER IS ISOLATED. ENSURE SEA WATER
IS ALIGNED TO THE COOLER PRIOR TO B/A SYSTEM
OPERATION. -UNQUOTE
(C) OPEN THE ISOLATION VALVES AND CIRCULATE SEA WATER
THROUGH THE COOLER FOR TEN MINUTES ONCE A DAY TO
REMOVE STAGNATED SEA WATER IAW REF C.
THE COOLERS SHALL REMAIN TAGGED AND ISOLATED UNTIL THE B/A SYSTEM
IS TO BE ACTIVATED OR THE SHIP IS MAKING PREPARATIONS TO GET
UNDERWAY.
B. FOR SHIPS WITH COOLERS EQUIPPED WITH MODIFIED FILL/DRAIN
VALVES, UTILIZE THE FOLLOWING PROCEDURE:
(1) ISOLATE AND TAG OUT THE COOLER IAW CURRENT SHIPBOARD
INSTRUCTIONS.
(2) OPEN DRAIN AND VENT VALVES, DRAIN COOLER.
(3) CONNECT FRESH WATER HOSE TO COOLER FILL CONNECTION AND
SHUT DRAIN VALVE.
(4) FILL COOLER WITH FRESH WATER UNTIL WATER APPEARS AT
VENT DRAIN AND REFILL WITH FRESH WATER.
(5) REMOVE HOSE, SHUT VENT VALVE AND REINSTALL FILL
CONNECTION END CAP.
(6) TAG IN COOLER LEAVING THE COOLER ISOLATION VALVES IN
THE SHUT POSITION.
(7) PLACE A CAUTION TAG ON THE COOLER ISOLATION VALVES AND
PACC GTM START PUSHBUTTONS AND EPCC GTG START
PUSHBUTTONS: QUOTE- PRAIRIE AND MASKER AIR COOLERS ARE
ISOLATED. ENSURE SEA WATER IS ALIGNED TO THE COOLERS
PRIOR TO B/A SYSTEM OPERATION.-UNQUOTE
(8) PERFORM THIS PROCEDURE EVERY TWO WEEKS WHILE IN LAY-UP
IAW REF C.
THE COOLER SHALL REMAIN ISOLATED UNTIL THE B/A SYSTEM IS TO BE
ACTIVATED OR THE SHIP IS MAKING PREPARATIONS TO GET UNDERWAY.
C. ALL CG 47 CLASS SHIPS SHALL UPDATE THE PRIOR TO UNDERWAY
CHECK OFF LIST TO INCLUDE ALIGNING THE PRAIRIE AND MASKER AIR
COOLERS PRIOR TO OPERATION OF BLEED AIR SYSTEM.
D. ALL CG 47 CLASS SHIPS ARE TO ENSURE THE BLEED AIR LOW
POINT DRAINS ARE FREE OF DEBRIS AND IN WORKING CONDITION.
4. EOSS.
A. PERMANENT EOSS CHANGES ARE BEING DEVELOPED FOR SHIPS
WITH MODIFIED COOLERS. CG 47 SHIPS EQUIPPED WITH MODIFIED
FILL/DRAIN VALVES SHALL SUBMIT A ROUTINE EOSS FEEDBACK REPORT
REFERENCING B/A HARDWARE CHANGES TO RECEIVE CORRECT EOSS.
B. FOR CG 47 SHIPS NOT EQUIPPED WITH MODIFIED COOLERS, MAKE
THE FOLLOWING PEN AND INK CHANGES TO EOSS:
1. FOR PROCEDURES BMAV, BMPA AND BSAA: REPLACE THE NOTE IN
THE SECURING PROCEDURE WITH QUOTE- NOTE: THE BLEED AIR SYSTEM IS
NORMALLY LEFT ALIGNED WITH THE EXCEPTION OF THE PRAIRIE AND
MASKER AIR COOLERS. THE PRAIRIE AND MASKER AIR COOLERS WILL BE
SECURED IN ACCORDANCE WITH CG 47 CLASS ADVISORY 06-93.
-UNQUOTE.
2. FOR PROCEDURE MUTA: ADD AN ADDITIONAL STEP TO THE END
OF PART IV, QUOTE- EOOW ORDER PRAIRIE AND MASKER COOLERS TO BE
SECURED (SP NO. BMPA). -UNQUOTE. HIGHLIGHT THIS PEN AND INK
CHANGE.
3. FOR PROCEDURE MUTS: ADD AN ADDITIONAL STEP TO THE END
OF PART VI, QUOTE- EOOW ORDER PRAIRIE AND MASKER COOLERS TO BE
SECURED (SP NO. BMPA). -UNQUOTE. HIGHLIGHT THIS PEN AND INK
CHANGE.
5. COMNAVSURFLANT/COMNAVSURFPAC - RECOMMEND TASK ALL CG 47 SHIPS
TO ADHERE TO PARA 3 AND 4 ACTIONS.
6. FOR CDNSWC (1423) - CONTINUE DEVELOPING EOSS PROCEDURES USING
PARAGRAPH 3 AND 4 GUIDANCE FOR SHIPS WITH MODIFIED BLEED AIR
COOLERS.
7. FOR CDNSWC (1413) - CHANGE PERIODICITY OF REF D PMS PROCEDURE
TO AN AS-REQUIRED CHECK TO BE ACCOMPLISHED WHENEVER THE BLEED AIR
SYSTEM IS TO BE SECURED FOR GREATER THAN 72 HOURS. MODIFY REF D
PROCEDURE TO INCORPORATE PARA 3.B GUIDANCE. REF D PMS PROCEDURE
CANNOT BE PERFORMED UNTIL BLEED AIR COOLER FILL/DRAIN VALVE
MODIFICATION HAS BEEN COMPLETED.
8. THIS CLASS ADVISORY HAS NO IMPACT ON CMMP AND WILL BE
CANCELLED WHEN REF D AND EOSS PROCEDURES BMAV, BMPA, BSAA, MUTS
AND MUTA HAVE BEEN MODIFIED.
9. ORIG POC IS MR. N. SMITHSON, PMS400F511, DSN 332-5959 OR COMM
(703) 602-5959. BLEED AIR SYSTEM TPOC IS MR. D. ELLIS, SEA
05Y3D, DSN 332-5728 OR COMM (703) 602-5728. HEAT EXCHANGER TPOC
IS MR. W. AERNI, SEA 05X23, DSN 332-6794 OR COMM (703)
602-6794.//