Preliminary Requirements

Safety Requirements

WARNING

IT IS THE RESPONSIBILITY OF THE OPERATOR TO OBTAIN AND OBSERVE THE MANUFACTURER"�S MATERIAL SAFETY DATA SHEETS FOR CONSUMABLE MATERIALS INFORMATION (SUCH AS HAZARDOUS INGREDIENTS; PHYSICAL/CHEMICAL CHARACTERISTICS; FIRE, EXPLOSION, REACTIVITY, AND HEALTH HAZARD DATA; PRECAUTIONS FOR SAFE HANDLING; USE AND CONTROL MEASURES), AND ALSO TO TAKE LOCAL REGULATIONS INTO CONSIDERATION.

Procedure

1. SUBTASK 70-12-12-300-001 Degrease the Part

   1. Chemically clean the part, if necessary. Refer to SPM TASK 70-11-03-300-503.

2. SUBTASK 70-12-12-300-002 Wet Bead Blast Procedure

   1. 

      CAUTION

      SURFACE TREATMENT (SUCH AS, ABRASIVE BLASTING), IF NOT DONE CORRECTLY, CAN CAUSE A SMEARED SURFACE. THIS MAKES SURFACE DEFECTS NOT EASY TO FIND DURING NON-DESTRUCTIVE INSPECTIONS. DIFFERENT MATERIAL AND PROCESSES WILL SHOW DIFFERENT EFFECTS. THUS IT IS VERY IMPORTANT TO FOLLOW VERY CAREFULLY THE INSTRUCTIONS IN THE STANDARD PRACTICES/PROCESSES MANUAL AND ENGINE MANUAL. IF CAREFULLY DONE, THE APPROVED NON-DESTRUCTIVE INSPECTION (ESPECIALLY FPI) WILL CONTINUE TO HAVE RESULTS THAT ARE VERY ACCURATE.

      

      CAUTION

      IT IS NOT PERMITTED TO MIX THE VARIOUS BLASTING MEDIA UNLESS PERMITTED BY A PROCEDURE.

      

      CAUTION

      THE USE OF ALTERNATIVE SIZE MEDIA OR MATERIAL TO THOSE SPECIFIED IN THE PROCEDURE IS NOT PERMITTED UNLESS SPECIFIED DIFFERENTLY BY THE ENGINE MANUAL.

      

      CAUTION

      THE BLASTING CABINET AND MEDIA USED IN THIS PROCEDURE ON ENGINE PARTS MUST NOT BE USED TO STRIP CADMIUM PLATED PARTS OR CADMIUM PLATED/PAINTED PARTS, SUCH AS LANDING GEAR.

      

      CAUTION

      ALWAYS APPLY MASKING TAPE OR INSTALL THE SPECIAL GUARDS TO THE COMPONENT SURFACES WHICH ARE NOT TO BE BLASTED. DO THIS BEFORE YOU BLAST THE COMPONENT. MAKE SURE NO BLASTING MEDIA GOES INTO THE COMPONENT AND BECOMES CAUGHT.

      Mask the part to prevent damage to identification mark and to prevent material entrapment.

   2. Set the machine air pressure at 40 psi to 50 psi (275.8 kPa to 344.7 kPa).

   3. 

      CAUTION

      USE GLASS BEADS ON HOT SECTION ENGINE PARTS WITH CAUTION. GLASS BEADS/PARTICLES THAT GET CAUGHT CAN CAUSE DETERIORATION OF MATERIAL.

      

      CAUTION

      DO NOT DWELL IN ANY ONE AREA FOR MORE THAN TWO SECONDS; USE CONTINUOUS MOTION.

      NOTE

      There must always be a 3 in. to 4 in. (76 mm to 102 mm) nozzle-to-part distance at 45 degree to 60 degree angle to the work distance.

      Blast with Solution Code 113 glass bead abrasive solution, as necessary, to remove scale. Refer to SPM TASK 70-12-12-100-501, SUBTASK 70-12-12-100-001.

   4. Pressure spray rinse with cold or hot water.

   5. Remove the masking.

      1. Put part fully in hot water at 150 deg F - 200 deg F (66 deg C - 93 deg C) until the temperature of the part increases sufficiently to flash dry.

         1. If the water on the part surface does not flash off when the part comes out of the hot water, then the time interval that the part stayed in the hot water was too short to increase the part temperature sufficiently.

   6. Blow dry with air at 30 psi (206.8 kPa) to remove any remaining water.

   7. Visually inspect the part to make sure all the blasting residue has been removed. Repeat as necessary to remove any residual residues.

   8. Apply a corrosion inhibitor, as necessary. Refer to SPM TASK 70-38-05-380-501.