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.//