Preliminary Requirements

Procedure

1. SUBTASK 72-32-85-350-083 Remove Defective Area of Damage

   1. 
      CAUTION
      THE FAN CASE IS MADE FROM TITANIUM ALLOY AND IS THIN IN SOME AREAS. IF YOU HIT THE FAN CASE WITH A CHIESEL OR SCRAPER YOU CAN MAKE IT UNSERVICEABLE.
      
      CAUTION
      YOU MUST USE THE CHISEL, SHARP BLADE OR SCRAPER IN A CIRCUMFERENTIAL DIRECTION TO PREVENT THE EDGES OF THE BLADE SCORING THE FAN CASE.
      
      CAUTION
      YOU MUST ALWAYS TRY TO POINT THE CHISEL OR SHARP BLADE PARALLEL WITH THE SURFACE OF THE FAN CASE.
      
      CAUTION
      STOP MACHINING AS SOON AS THE FILES, CUTTERS OR MACHINING BITS ARE THROUGH THE LINING MATERIAL. USE A STOP-MACHINING OR SLEEVE OR OTHER PENETRATION LIMITING DEVICE TO PREVENT DAMAGE TO THE CASING MATERIAL.
      
      CAUTION
      DO NOT USE POWERED TOOLS WITH STEEL CHISEL OR SIMILAR BITS.

      Remove damaged material from repair area.

      1. Use CoMat 05-016 GARNET PAPER, 80-GRIT.

      2. Take care not to damage the anti ice impact panel and acoustic lining. Refer to Figure.

      3. Be careful not to cause damage to inner surface of the fan case assembly.

   2. 
      WARNING
      DO NOT OPERATE WITHOUT SAFETY GOGGLES AND OTHER GUARDS EQUIPMENT. FLYING MATERIAL CAN CAUSE EYE INJURY.

      NOTE

      Keep the material removal to the minimum necessary to remove damaged area.

      Examine the anti ice impact panel and acoustic lining.

      1. If damage, repair, refer to VRS1555 TASK 72-32-85-300-023 and/or VRS1559 TASK 72-32-85-300-021.

   3. Remove any remaining debris with dry air blast and/or vacuum cleaner.

   4. Examine the fan case inner surface of the repair area.

      1. Examine the fan case inner surface. If necessary repair any nicks, dents, scratches and gouges.

      2. If necessary, do repair VRS1554 TASK 72-32-85-300-016 (REPAIR-016).

2. SUBTASK 72-32-85-110-056 Remove the Grease from the Repair Area

   1. 
      WARNING
      AIR BLAST CREATE FLYING PARTICLES. YOU MUST USE THE SAFETY SHIELD AND OTHER PROTECTIVE EQUIPMENT. FLYING PARTICLES CAN CAUSE EYE INJURY.
      
      WARNING
      ALWAYS MAKE SURE THERE IS SUFFICIENT VENTILATION IN THE WORK AREA. EYE PROTECTION MUST ALWAYS BE USED. DO NOT LET THE SOLVENT CLEANER OR ITS VAPOR TOUCH THE EYES OR SKIN. PROTECTIVE CLOTHING AND FACE MASKS MUST ALWAYS BE USED. ALWAYS KEEP OPEN FLAMES AWAY FROM THE WORK AREA. IT IS THE RESPONSIBILITY OF THE OPERATOR TO OBTAIN AND OBSERVE THE MANUFACTURERS MATERIAL SAFETY DATA SHEETS FOR CONSUMABLE MATERIALS INFORMATION SUCH AS, HAZARDOUS INGREDIENTS, PHYSICAL/CHEMICAL CHARACTERISTICS, FIRE EXPLOSION, REACTIVITY, HEALTH HAZARD DATA, PRECAUTIONS FOR SAFE HANDLING, USE AND CONTROL MEASURES AND ALSO TO TAKE LOCAL REGULATIONS INTO CONSIDERATION.

      Fully remove any grease from the repair area except the blue filler surface.

      1. Refer to the SPM TASK 70-11-26-30-503.

      2. Use CoMat 01-076 METHYL ETHYL KETONE, CoMat 01-124 ISOPROPYL ALCOHOL or coMat 01-031 acetone with CoMat 02-099 LINT-FREE CLOTH.

   2. Immediately dry out the area with air blast.

      1. Use oil free dry air.

3. SUBTASK 72-32-85-360-064 Prepare Filler Material

   1. Prepare the filler (CoMat 08-006 FILLER, TWO PACK).

   2. Measure out materials by weight.

      1. Refer to TASK 70-36-02-360-501.

      2. Use CoMat 08-006 FILLER, TWO PACK.

   3. Mix the two parts by kneading, until the paste is a constant blue color. No streaks permitted.

      1. Use putty knife.

   4. Prepare the sealant (CoMat 08-024 SEALANT or CoMat 08-142 POLYSULPHIDE COMPOUND).

   5. Measure out materials by weight.

      1. Use CoMat 08-024 SEALANT 75 parts of base compound and 10 parts of curing compound (accelerator) or CoMat 08-142 POLYSULPHIDE COMPOUND 100 parts of base compound 10 parts of curing compound (accelerator) by weight.

   6. NOTE

      You must use plastic gloves during preparation and use of the sealant to prevent contamination of the skin.

      NOTE

      When mixed the life of the filler is approximately half an hour at 77 deg F (225 deg C).

      Mix the two parts by kneading until the compound is a constant color. No streaks permitted.

      1. Use putty knife.

4. SUBTASK 72-32-85-360-065 Apply Filler Material

   1. Option 1: Apply the filler (CoMat 08-006 FILLER, TWO PACK).

   2. Fill the filler slightly more than necessary level, in the damaged area.

      1. Refer to the SPM TASK 70-36-02-360-501.

      2. Use air powered sealant gun or equivalent. Make sure that the repair area is fully filled with no air pockets. Start at the bottom and work both sides. The filler will gradually set. If any sagging is apparent, locally produced supports will be necessary.

   3. Cure the filler.

      1. The cure times and temperatures are given in Figure.

   4. 
      CAUTION
      THE MAXIMUM TEMPERATURE WHICH CAN BE USED TO CURE THE FILLER IS 176 DEG F (80 DEG C).

      NOTE

      The minimum cure time is one hour.

      Option 2: Apply the sealant (CoMat 08-024 SEALANT or CoMat 08-142 POLYSULPHIDE COMPOUND).

      1. Make sure that the repair area is fully filled with no air pockets. Start at the bottom and work both sides. The filler will gradualy set. If any sagging is apparent, locally produced supports will be necessary. Cure the sealant for 10 hours at 77 deg F (25 deg C) or 1.5 hours at 113 deg F (45 deg C).

   5. 
      CAUTION
      THE MAXIMUM TEMPERATURE WHICH CAN BE USED TO CURE THE SEALANT IS 120 DEG F (49 DEG C).
      
      CAUTION
      DO NOT OPERATE WITHOUT SAFETY GOGGLES AND OTHER GUARD EQUIPMENT. FLYING PARTICLES CAN CAUSE INJURY.

      NOTE

      The minimum cure time is 1.5 hours. Sealant cure times with relative humidity of 50 percent.

      Blend the filler to the contours.

      1. Use CoMat 05-016 GARNET PAPER, 80-GRIT.

      2. Refer to Figure.

   6. Remove debris.

      1. Use Vacuum cleaner.

5. SUBTASK 72-32-85-220-098 Examine the Repair Area

   1. Examine the surface of repair area.

      1. Make sure that filled surface is smooth. A step is acceptable if less than 0.02 in. (0.5 mm). If necessary, do this TASK again. Refer to Figure.

Figure: Filling repair the gap

Filling repair the gap



Figure: Curing chart of filling material (CoMat 08-006)

Curing chart of filling material (CoMat 08-006)