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. THESE CONTAIN 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.

Procedure

1. SUBTASK 72-41-11-180-001 Make-up and Control of the Nitric Acid Solution

   1. Do Step or Step.

2. SUBTASK 72-41-11-180-001-001 Make-up and Control of the Nitric Acid Solution

   1. Make-up the nitric acid solution.

      1. Refer to SPM TASK 70-33-89-100-501 for the procedure to make-up the nitric acid solution.

   2. Control of the nitric acid solution.

      1. Refer to SPM TASK 70-33-89-200-502 for the procedure to control the nitric acid solution.

   3. Operating temperature of the nitric acid solution.

      1. The operating temperature range of this solution for this task is 59 deg F - 77 deg F (15 deg C - 25 deg C).

3. SUBTASK 72-41-11-180-001-002 Make-up and Control of the MTC610 Nitric Acid Solution

   1. This is an aqueous solution of CoMat 01-262 NITRIC ACID or CoMat 01-263 NITRIC ACID.

      1. The make-up concentration is approximately 80 percent by volume for CoMat 01-262 NITRIC ACID or approximately 60 percent by volume for CoMat 01-263 NITRIC ACID.

      2. The operating limits of the solution are 69.4 oz.wt/gal - 77.4 oz.wt/gal (520 g/l - 580 g/l) HNO3.

   2. Make-up the MTC610 nitric acid solution.

      1. Fill the tank to one third of its operating volume with demineralized water.

      2. Add the necessary amount of CoMat 01-262 NITRIC ACID or CoMat 01-263 NITRIC ACID slowly and carefully. Stir well to mix.

      3. Fill the tank to its operating level with demineralized water.

      4. Increase the temperature of the solution to the specified temperature.

   3. Control of the MTC610 nitric acid solution.

      1. Refer to SPM TASK 70-33-89-200-502 for the procedure to do the test and control of solutions used to nitric acid clean.

   4. Operating temperature of the MTC610 nitric acid solution.

      1. The operating temperature range of this solution for this task is 95 deg F - 113 deg F (35 deg C - 45 deg C).

4. SUBTASK 72-41-11-180-002 Make-up and Control of the Conditioner Solution

   1. Make-up the conditioner solution.

      1. 

         WARNING

         AT THE SOLUTION OPERATING TEMPERATURE, CARBONATION OF THE SOLUTION OCCURS, WHICH CAUSES SLUDGE TO COLLECT AT THE BOTTOM OF THE SOLUTION TANK. IT IS NECESSARY TO REMOVE THIS SLUDGE AT FREQUENT INTERVALS TO DECREASE THE RISK OF EXPLOSION.

         This is an aqeous solution of CoMat 01-042 CONDITIONER. The solution tank must be a stainless steel tank that has stainless steel heater coils on the side or sides of the tank and an exhaust system to remove fumes. The heater coils must not be on the bottom of the tank.

      2. Use the applicable procedure in the subsequent list to make the solution. Do not mix one CoMat 01-042 letter suffix alternative material with a different CoMat 01-042 letter suffix material.

         1. Procedure for CoMat 01-042A CONDITIONER, CoMat 01-042B CONDITIONER or CoMat 01-042C CONDITIONER:

            1. To make-up the solution, fill the tank to approximately two thirds of the operating volume with clean, cold water.

            2. Slowly and carefully add the necessary amount of CoMat 01-042A CONDITIONER, CoMat 01-042B CONDITIONER or CoMat 01-042C CONDITIONER to get a concentration of 73.43 oz.wt/gal to 101.48 oz.wt/gal (550 g/l to 760 g/l). Stir constantly or agitate slowly with air, as you add the conditioner to the water.

            3. Carefully fill the tank to the operating volume.

            4. Increase the temperature of the solution to 185 deg F to 203 deg F (85 deg C to 89 deg C).

         2. Procedure for CoMat 01-042D CONDITIONER:

            1. Carefully fill the tank to the operating volume with CoMat 01-042D CONDITIONER.

            2. Increase the temperature of the solution to the operating temperature range of 176 deg F to 194 deg F (80 deg C to 90 deg C).

   2. Control of the conditioner solution.

      1. Use the manufacturer's instructions to do the control and maintenance of the solution.

      2. Do not mix one CoMat 01-042 letter suffix alternative material with a different CoMat 01-042 letter suffix material.

5. SUBTASK 72-41-11-110-120 Clean the Part to Remove Oxidation and/or Silver Residue

   1. 

      CAUTION

      PARTS WITH METAL SPRAY OR PLATED COATINGS CAN BE ATTACKED BY NITRIC ACID OR OXIDE CONDITIONING SOLUTIONS. METAL SPRAYED AND OTHER PLATED COATINGS MUST BE MASKED TO THE SPM TASK 70-11-35-110-501 BEFORE THE PART IS PUT INTO THESE SOLUTIONS. IF THE PART IS PROCESSED WITHOUT A MASK, THE COATING MUST BE REPLACED.

      Make sure the part is fully clean.

   2. Mask all metal sprayed, or other plated coatings. Refer to SPM TASK 70-11-35-110-501.

   3. Put the part fully into the conditioner solution (refer to Step) at the applicable temperature for one hour. Rotate the part, as necessary, to make sure all surfaces are touched by the conditioner solution.

      1. Refer to Step for the applicable solution operating temperature.

   4. Put the part fully in clean cold water. Rotate the parts to make sure all surfaces are washed fully.

   5. Pressure wash with one of the items in the subsequent list to remove the silver residues.

      1. Air-assisted water gun.

      2. High pressure water spray unit (power washer) that has a fan spray nozzle or an oscillating nozzle (also known as a rotary, rotating or turbo nozzle). The water pressure that the high pressure spray unit can supply must not be more than 2000 psig (13.8 MPa).

   6. Put the part fully into the nitric acid solution (refer to Step) at the applicable temperature (refer to Step and Step). Agitate the solution with air. Keep the part in the solution for 30 minutes. Rotate the parts as necessary to make sure the nitric acid solution touches all surfaces.

      NOTE

      As an alternative to one 30 minutes cycle, the part can be kept in the solution for one 60 minutes cycle.

   7. After completion of the initial cleaning procedure examine the HP Compressor Stage 3 - 8 Disks.

      1. No oxidation and/or silver residue remaining on the component.

         1. Accept.

      2. Oxidation and/or silver residue still remaining on the component continue as follows:

         1. Inform IAE tech services about the finding, specifying component part number, serial number, part time and cycles since new and since last shop visit, engine serial number and operator name.

         2. Do a cleaning procedure as in Step. The time in the nitric acid bath can be extended upto maximum five hours additionally from Step.

         3. Examine the HP Compressor Stage 3 - 8 Disks.

            1. Oxidation and/or silver residue still remaining on the component.

               1. Reject.

            2. Continue the Step if no oxidation and/or silver residue remaining on the component.

   8. Put the part fully in clean cold water. Rotate the parts to make sure all surfaces are washed fully.

   9. Pressure wash with an air-water gun, at a maximum pressure of 2000 psig (14 MPa) to remove residues.

      NOTE

      It is not necessary to use the maximum pressure of 2000 psig (14 MPa).
   10. 

       CAUTION

       THE CLEAN HOT WATER RINSE SHALL BE MADE UP WITH WATER THAT CONTAINS NOT MORE THAN 100 PPM CHLORIDE, OR HALIDE. THE QUANTITY OF CHLORIDE, OR HALIDE, IN THE WATER SHALL NOT BE MORE THAN 250 PPM.

       Put the part fully in clean hot water at 176 deg F (80 deg C) minimum. Remove and dry with a blast of clean dry air.

   11. Remove the masking. Refer to SPM TASK 70-11-04-300-503 and examine the surface lining.

   12. Examine the surface lining.

       1. The surface lining is not cracked, spalled or discoloured.

          1. Accept.

       2. Other than surface lining conditions.

          1. Refer to Repair, VRS6007 TASK 72-41-11-300-002 (REPAIR-002).

   13. Oven dry for one hour at 320 +/- 72 deg F (160 +/- 40 deg C).