SULPHURIC ACID ANODIZING KJ ATTACHMENT NO. 2 TO KJ-06

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1 KJ ATTACHMENT NO. 2 TO KJ-06 KJ translated by: Justyna Kilian; Date: 02/22/2017 Compiled by: Małgorzata Groele Dział Techniczny DTT-8 Approved by: Dariusz Nykiel Process Engineering Office Director

2 Attachment to KJ-06 KJ Page 2 of 8 Chief Process Engineer 1. Purpose of the document The purpose of this document is to regulate the basic rules for sulfuric acid anodizing process of aluminum and aluminum alloys, performed by suppliers on parts delivered to Polskie Zakłady Lotnicze Sp. z o.o. 2. Subject of the document The subject of this document are requirements regarding sulfuric acid anodizing process and control of parts which are subjected to anodizing process. 3. The scope of document application All requirements specified herein apply to all suppliers and should be met in scope specified in a purchase order / agreement / contract. 4. Related documents Range of application of reference documents relates to their current issue. ITT ASTM B 244 FED-STD-141 ASTM B 137 Instr ASTM B 117 Sulphuric acid anodizing of aluminium and aluminium alloys. Standard test method for measurement of thickness of anodic coatings on aluminum and of other nonconductive coatings on nonmagnetic basis metals with eddy-current instruments Paints, varnish, lacquers and related materials : inspection methods, sampling and testing. Standard test method for measurement of coating mass per unit area on anodically coated aluminum. Anodic oxidation aluminium alloys. Standard Practice for Operating Salt Spray (Fog) Apparatus. 5. Additional information 5.1. Classification of the coatings ITT defines following types and classes of the coatings: Type TYP II Class Description Sulphuric acid anodizing, conventional coatings. Description 1 Class Coloure less Sealing classes Klasa A Non-sealed coating Description

3 Attachment to KJ-06 KJ Page 3 of 8 Klasa B Klasa C Sealed coating in hot demineralized water with natural color of substrate Sealed coating in chromate solution or trivalent chromium salts, not coloured. If design documentation contains a record which requires anodizing in accordance with PN-EN 2284, then requirements which refers to the process should refer to above record General notices. a) For every part, detail technology should be prepared. b) Parts for anodizing should be free from foreign substances, oxides and dirt s like greases, oils, paint, welding flux. Apply preparation process in order to get entirely wettable surface before anodizing. Using abrasive materials contained iron for mechanical cleaning is forbidden, in effect, it could accelerate aluminum alloys corrosion. c) The parts shall be anodized after complete machining, heat treatment, welding, and penetrant inspection. The surface of parts subjected to anodizing shall be free from surface defects which may cause that produced anodic coating will not meet the requirements of this specification. The surface defects may be caused by machining, cutting, scratching, polishing, bending, stretching, etching, chemical composition imbalance and inclusions. d) Before anodizing non- aluminum elements should be removed or protect before contact with sulfuric acid. Surfaces not subjected to anodizing shall be masked with a stoppers, turco lacquer or aluminum tape. e) Devices directly used in anodizing process as controllers, temperature indicators, ammeters, voltmeters, shall be periodically checked. f) Contact places with devices shall be limited to minimum g) Following process operations perform without excessive intervals in order to avoid parts drying. h) Compressed air used to mix the solution and water in rinse water baths shall be free of oil, water and solid particles. i) Before anodizing non- aluminum elements should be removed or protect before contact with sulfuric acid. j) Use additional internal cathodes to anodizing parts with deep cavities or to internal surface of pipes, when length- to internal diameter ratio is bigger than 15:1. k) It is allowed to handle wet parts only in rubber gloves, while dry parts only in clean cotton gloves. l) Cathode and anode bars maintain in cleanness. m) It is recommended to separately anodize the alloys of different grade n) Anodizing parts should be totally immersed in bath. o) Re-anodizing may be performed after removal of previous anodic coating and inspection if coating has been removed. p) Priming after anodizing shall be performed within the shortest time as it is possible to have parts exposed to contamination for a minimum time. q) Thickness of the anodic coating shall be conforming with requirements specified in conditions of supply. r) In the quality report, record the date and hour of anodizing process finish and anodic coating thickness results.

4 Attachment to KJ-06 KJ Page 4 of 8 s) Anodized parts protect against damage. Recommended packing material: clean, soft not paraffined paper, special pallets. There should be no contact between parts Non-conforming parts Follow requirements defined in KJ-06 para Proceeding description Process qualification procedure. Anodizing process in sulphuric acid is one of special processes and requires qualification in production conditions. In the case when special process realized in accordance with defined requirements at supplier was approved by one from the firms of UTC Corporation, this qualification can be automatically recognized by Polskie Zakłady Lotnicze Sp. z o.o. It is allowed to approve the special process at supplier basing on its manufacturing/ technological process, if previously approved by design engineer of Polskie Zakłady Lotnicze Sp. z o.o. Then such special process has a status of frozen process at supplier. Every change in the approved process requires repeated acceptance of the design engineer. During preliminary Supplier qualification, Polskie Zakłady Lotnicze Sp. z o.o. reserve the right to participate in a process performed on parts and specimens at new Supplier facility and possibility to perform control quality tests on parts or specimens processed by Supplier. Polskie Zakłady Lotnicze Sp. z o.o. qualification team shall conduct qualification audit of the special process at supplier, keeping the following steps: a) Inspection of devices and review of the metrological confirmation records. Verify if: devices have equipment to control parameters of special process work with required accuracy, the whole measuring equipment used to control the correct course of the process (or some parameters) is in proper place secured from aggressive atmospheric conditions, used materials meet technical and quality requirements, there is a record regarding periodical review of the devices and metrological confirmation of used measuring equipment, process meets requirements of standards regarding environment protection and safety of the work. b) Review of the documents and special process instruction. Qualification team shall check if: technical documentation necessary to perform process is complete and current, process engineering and quality instruction regarding given process are accurate and intelligible taking into account included requirements; instructions shall be available on the work stand, products identification is ensured via their registering on the work stand. c) Knowledge and personnel practical abilities.

5 Attachment to KJ-06 KJ Page 5 of 8 Qualification team shall check if: personnel realizing process have required qualification documentation, personnel is authorized to perform special processes, all changes of the personnel are registered. Change of the personnel may cause necessity to perform repeated first article inspection. d) Realization of the special process on a specimen or product. Special process is performed on specimens or products in accordance with Polskie Zakłady Lotnicze Sp. z o.o. requirements. It is required to check the sequence of performed activities and correctness of process parameters determination. It is required also to verify if tests of specimens and products are performed on controlled and calibrated equipment. e) Results analysis. Qualification team heaving authorization of auditors prepares report from audit performed at supplier facilities. Documents prepared by supplier during internal qualification are attached Change in the special process. Every change regarding device, conditions, instruction or personnel at supplier facilities shall be reported by process owner to Supplier Quality Assurance Department Manager in Polskie Zakłady Lotnicze Sp. z o.o., which makes decision regarding needs of the new qualification. The change cannot be introduced until permission is obtained to apply the change. Audit performed by qualification team at supplier facilities is not necessary in the case, when special process conducted on a new equipment obtained qualification on equipment used up to now. In this case decision about qualification may be issued basing on inspection of internal qualification documents passed by process supplier Quality inspection of manufacturing series. a) Inspection processes and final acceptance of parts shall confirm conformity with parameters of qualification process. b) Conduct visual inspection of parts. c) Conduct register of records of quality acceptance. d) Time of keeping of quality records (test sheet, report of tests, registers, etc.) is 10 years. e) Periodically analysis of baths shall be conducted with frequency which guarantees a good quality of coating. Analysis results, make ups and bath change shall be registered. f) Control current and temperature parameters on measuring devices. g) Conduct the coating thickness tests on the parts h) Conduct corrosion resistance tests, paint coating adherence tests, mass tests on specimens for inspect the process control. i) Control lack of pollution like water, oil, etc. in compressed air applied in inspection process Methods of inspection and requirements. a) Parts are subjected to visual inspection, coating thickness inspection. b) On specimens to approve and control the process following tests are conducted: corrosion resistance inspection

6 Attachment to KJ-06 KJ Page 6 of 8 paint coating adherence inspection coating mass inspection Results are compiled in form of reports from test. c) Defining the specimens. Specimens shall be processed with production parts. Specimens to test prior to anodizing shall be carefully looked round. Those shall not have visible contaminants, defects as corrosion, inclusions and delaminations Parts inspection. Notes: Inspection carry out in clean cotton gloves Visual inspection of parts a) Visual inspection perform on 100% parts of every production batch. b) Anodic coating before sealing shall have a light,metallic color with a shade and uniformity depending on the condition of the part surface and alloy grade. After sealing in hot water, metallic coating does not change the appearance in the visible way. Sealing in the chromium salts causes that the coating has a yellow-green shadow with intensity depending on coating thickness. The coating shall be continuous, smooth, without powdered areas. c) The following is not allowed: deep scratches injuring anodic coating, loose coating, blurring during wiping ( a light deposit of the salt removed during wiping is not a defect), spot scale, white spots, dark spots which are evidence of the welding - if not specified in the job card, different shadows of the coating or dark coating which indicates incorrect heat treatment or missing heat treatment ( do not refer to AMc and AMg alloys). In the questionable cases, parts on which there is a suspect of welding or incorrect heat treatment shall be passed to laboratory for tests. d) Missing coating is allowed in places of contact with clamps of rack, different shadows of the coating depending on alloy grade and in places with a specific surface condition i.e. welding, rubbing, crumple, extrusion, roll out, surfaces with damaged clad coating. Missing coating is allowed in blind holes and places of gas blisters arising during anodizing of parts with complex shapes provided that these places are primed. Light discoloration as a result of draining of the sealing solution from constructional gaps in the parts are allowed Thickness inspection of anodic coating. a) Anodic coat thickness should be measured on 3-5 pieces from the load. The measurement shall be performed in a few places on the part surface with non-destructive eddy current method in accordance with ASTM B244, using eddy-current device or other device accepted by PZL. Sp. z o.o. The thickness of the coating can be measured in the laboratory at the abrasive section by a microscope

7 Attachment to KJ-06 KJ Page 7 of Specimens inspection. Compilation of tests on specimens witnesses of sulphuric acid anodizing process for production batch and process control is listed below. Type of test Corrosion resistance Coating adherence Mass of the non-sealed coating Tests frequency Once per month Specimens dimensions [mm] 254x76x0,64-1,60 Once per month 254x76x0,64-1,60 Once per month 76x76x0,64-1,60 Quantity Material T3 per AMS- QQ-A-250/4 or AMS T3 per AMS- QQ-A-250/4 or AMS T3 per AMS Except for periodical testing, corrosion resistance test and coating mass test, perform also in the case when the anodizing process is changed : for example when used deoxidizing agent or sealing bath other than approved Corrosion resistance inspection Specimens to corrosion resistance inspection shall be anodized to the thickness 5-8 micrometers and sealed. Perform the test in the salt chamber, using 5% solution of NaCl for 336 hours in accordance with ASTM B117. Specimens shall be located at an angle 6 degrees from the vertical with tested surface. After the test, there shall be no more than 15 separate pits of diameter not larger than 0.8mm (1/32 inch) on a total surface 697,5 square cm (150 square inch) and not more than 5 separate pits of diameter not larger than 0,8mm (1/32 inch) on the surface 193,5 square cm ( 30 square inch) Paint coating adherence inspection Adherence test shall be performed on anodized test specimens finished with organic coating of the primer used at PZL. Adherence test shall be performed in accordance with FED-STD-141 method During the test, there shall be no separation between paint and anodic coating or between anodic coating and base metal Mass coating inspection Mass coating measurement shall be performed in accordance with ASTM B137.

8 Attachment to KJ-06 KJ Page 8 of Process inspection. Perform process control once a month. Additionally, when process is not carried out in 1 month period or longer, samples shall be made at the beginning of production. Inspection contains tests below in conformity with following requirements: 1. Control of process course parameters. 2. Coat appearance. 3. Coat thickness.. 4. Corrosion resistance inspection. 5. Paint coating adherence inspection. 6. Coating mass inspection.