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, HEALTH HAZARD DATA, PRECAUTIONS FOR SAFE HANDLING, USE AND CONTROL MEASURES AND ALSO TO TAKE LOCAL REGULATIONS INTO CONSIDERATION.

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

DO NOT USE THIS PROCEDURE FOR CLEANING OR STRIPPING TITANIUM PARTS BEFORE FPI. FOR OTHER PARTS, WHEN THIS PROCEDURE IS SPECIFIED FOR CLEANING PARTS BEFORE FPI OR FMPI THE PART MUST FIRST BE CLEANED BY THE SPM TASK 70-11-13-300-503 OR SPM TASK 70-11-16-300-503, WHICHEVER IS SPECIFIED IN THE 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

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

CAUTION

DO NOT PURCHASE RECYCLED/RECOVERED MATERIAL, USE ONLY NEW ALUMINIUM OXIDE ABRASIVE.

Procedure

1. SUBTASK 70-12-02-860-001 Equipment and Material

   1. Consumable materials

      CoMat 05-001 ABRASIVE MEDIUM, ALUMINIUM OXIDE, 20/30 GRADE	Aluminum oxide 20 grade
      CoMat 05-002 ABRASIVE MEDIUM, ALUMINUM OXIDE	Aluminum oxide 60/80 grade
      CoMat 05-003 ABRASIVE MEDIUM ALUMINUM OXIDE, 120/220 GRADE	Aluminum oxide 120/220 mesh
      CoMat 05-004 ABRASIVE MEDIUM, ALUMINUM OXIDE, 140/400 GRADE	Aluminum oxide 140/400 mesh
      CoMat 05-015 ABRASIVE MEDIUM, ALUMINUM OXIDE	Aluminum oxide 54 grade
      CoMat 05-022 ALUMINUM OXIDE ABRASIVE	Aluminum oxide 240 abrasive
      CoMat 05-035 ALUMINUM OXIDE ABRASIVE	Aluminum oxide abrasive No 90
      CoMat 05-041 ALUMINUM OXIDE GRIT	Aluminum oxide abrasive No 24
      CoMat 05-046 ALUMINUM OXIDE GRIT	Aluminum oxide abrasive No 60
      CoMat 05-068 DELETED	Aluminum oxide sieve 75-45
      CoMat 05-155 ALUMUNUM OXIDE ABRASIVE,27 MICRON	Aluminum oxide abrasive 27 micron
      CoMat 05-156 ALUMINUM OXIDE ABRASIVE	Aluminum oxide abrasive 500 grit
      CoMat 05-161 DELETED	Aluminum oxide abrasive 60 grit
      CoMat 05-164 DELETED	Aluminum oxide abrasive 46 grade
      CoMat 05-192 ALUMINUM OXIDE GRIT	Aluminum oxide abrasive No 60
      CoMat 05-193 ALUMINUM OXIDE, 90-GRIT	Aluminum oxide abrasive No 90
      CoMat 05-194 ALUMINUM OXIDE, 120- GRIT	Aluminum oxide abrasive No 120
      CoMat 05-195 ALUMINUM OXIDE, 150-GRIT	Aluminum oxide abrasive No 150
      CoMat 05-196 ALUMINUM OXIDE, 180-GRIT	Aluminum oxide abrasive No 180
      CoMat 05-197 ALUMINUM OXIDE, 240-GRIT	Aluminum oxide abrasive No 240
      CoMat 05-198 ALUMINUM OXIDE, 320-GRIT	Aluminum oxide abrasive No 320
      CoMat 05-199 ALUMINUM OXIDE, F500 GRIT	Aluminum oxide abrasive No 500
      CoMat 05-230 ABRASIVE MEDIUM ALUMINUM OXIDE, 280/500 GRADE	Aluminum oxide abrasive 280/500
      NOTE To identify the consumable materials refer to the PCI.

2. SUBTASK 70-12-02-120-001 Make-up and Control of Non-Metallic Abrasives

   
   CAUTION
   THE ABRASIVE GRITS MUST BE LEAD-FREE VIRGIN FUSED ALUMINA. CONTAINING LESS THAN 5 P.P.M. ELEMENTAL LEAD AND LESS THAN 20 P.P.M. TOTAL LEAD COMPOUNDS, WITH IRON CONTENT AS ACID EXTRACTABLE IRON NOT MORE THAN ONE PERCENT. SEE EXAMPLES OF COMPOUNDS BELOW:

   1. Examples of virgin fused alumina compounds.

      Aluminum oxide (Al2 O3) 99.3 percent minimum.

      Silicone dioxide (Si O2) 0.02 percent maximum.

      Titanium dioxide (Ti O2) 0.01 percent maximum.

      Chromium oxide (Cr2 O3) 0.25 percent maximum.

      Calcium oxide (CaO) 0.02 percent maximum.

      Magnesium oxide (MgO) 0.01 percent maximum.

      Iron oxide (FeO) 0.25 percent maximum.

      Alkali metal, sodium and potassium 0.25 percent maximum.

3. SUBTASK 70-12-02-120-002 The Procedure to Use Dry Non-Metallic Abrasive Blasting

   
   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.

   1. Clean the components to remove the grease and the dirt as given in the Engine Manual.

   2. Seal all the areas that are not to be blasted.

   3. Put the components on to the platform in the blasting cabinet or hold in a gloved hand.

      NOTE

      For pressure feed machines, the air pressures must not be more than 40 psi (280 KPa), and for suction machines pressures greater than 80 psi (560 KPa) unless specifically permitted in the Engine Manual. Pressures as low as 15 psi (75 KPa) can be used on some parts and produce satisfactory results.

   4. Point the blast systematically on the surface to be blasted for a minimum time necessary to clean the components. For pressure feed machines, use an air pressure of 20 to 40 psi (140 to 280 KPa). for suction feed machines a pressure of up to 80 psi (560 KPa) may be used. The actual pressure used shall be controlled by the material and its condition, component section and thickness and the permitted quantity of metal removal.

4. SUBTASK 70-12-02-120-003 The Procedure After Dry Non-Metallic Abrasive Blasting

   NOTE

   When it is not necessary to do more procedures or protective treatment on a steel component, it must have temporary protection as referred to in the SPM TASK 70-38-05-380-501.

   1. Remove all unwanted grit with the use of a dry air blast or a soft brush. In some cases for example, before bonding, a vacuum brush must be used to remove all grit.

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