Finishing materials by nickel and chromium plating
Overview
This standard identifies the competencies you need to carry out nickel and chromium plating processes to various substrates, in accordance with approved procedures. You will be required to access the appropriate specifications, to check that these are f the current issue and to extract all necessary information in order to carry out the nickel and chromium plating operations. You will be required to carry out all necessary preparations to the base materials prior to plating them and this will include such items as cleaning, degreasing, masking and other appropriate treatments.
You will be expected to prepare and adjust the plating solutions to give satisfactory deposits at optimal productivity levels. You will be expected to identify any plating defects and to carry out the necessary actions and adjustments to equipment and plating solutions in order to correct them. You will need to carry out tests on the components to ensure that deposited layers meet their specification requirements.
Your responsibilities will require you to comply with organisational policy and procedures for the nickel and chromium plating activities undertaken and to report any problems with these activities or with the materials and equipment used, that you cannot personally resolve, or are outside your permitted authority, to the relevant people. You will be expected to work with a minimum of supervision, taking personal responsibility for your own actions and for the quality and accuracy of the work that you carry out.
Your underpinning knowledge will provide a good understanding of your work and will provide an informed approach to applying nickel and chromium plating methods, techniques and procedures. You will understand the nickel and chromium plating processes and their application, in adequate depth to provide a sound basis for carrying out the activities, correcting faults and ensuring the finished components are to the required specification. Your knowledge will also include effluent treatment, for the waste streams from the nickel and chromium plating processes and their associated pre-treatments.
You will understand the safety precautions required when carrying out the preparation and nickel and chromium plating operations. You will be required to demonstrate safe working practices throughout and will understand the responsibility you owe to yourself and others in the workplace and towards the environment.
Performance criteria
You must be able to:
1. work safely at all times, complying with health and safety legislation, regulations, directives and other relevant guidelines 2. follow relevant job instructions and specifications 3. ensure the material surfaces to be treated are prepared for the finishing operations 4. check that the finishing equipment and treatment solutions are set up and maintained at required operating conditions and levels 5. carry out finishing according to operating procedures and to meet specifications 6. check that the treated workpiece achieves the required characteristics and meets the finishing specifications 7. deal promptly and effectively with problems within your control and report those that cannot be solved 8. ensure that work records are completed, stored securely and available to others, as per organisational requirements 9. leave the work area in a safe condition on completion of the activities, as per organisational and legal requirements |
Knowledge and Understanding
You need to know and understand:
1. the specific safety precautions to be taken whilst carrying out the activities (including any specific legislation, regulations or codes of practice relating to the activities, equipment or materials) 2. the health and safety requirements of the work area and the activities, and the responsibility these requirements place on you 3. the hazards associated with the activities, and how to minimise them and reduce risks 4. the personal protective equipment and clothing (PPE) to be worn during the activities 5. the importance of a clean and tidy work environment including the use of 5S or similar techniques 6. the importance of extraction on nickel and hexavalent chromium solutions, inspection of equipment for damage and effectiveness, and measurement of metals in the atmosphere above the plating solutions 7. the types of specifications that are used for the nickel and chromium plating activities 8. how to assess component suitability for nickel or chromium plating (suitable methods of handling, methods of pre-treatment, the plating material to use, the most efficient and appropriate method of application) 9. how to identify coating specifications and advise on correct coating thicknesses and combinations to meet specific service requirements 10. the basic principles of operation of the nickel and chromium plating equipment 11. how to set up and check that the plating plant, equipment and solutions are fit for purpose 12. properties of nickel and chromium electro-deposits 13. the mechanisms of corrosion protection arising from an electroplated deposit as a surface layer 14. the properties of different passivation and the effects of sealants and torque control additives 15. how to assess component suitability forrack or barrel plating, jigging or wiring techniques 16. how to make up plating solutions and pre-treatment solutions, safely and correctly 17. how to clean and prepare substrates and check for cleanliness 18. how to examine components for visible defects prior to plating them 19. the suitability of various substrates for nickel and chromium plating, the special pre-treatments required for plastics and zinc based die castings 20. limitations of geometry and its effect on throwing power 21. how to test coated components for specification compliance 22. how to identify processing faults and how to correct them 23. how to remove poorly applied coatings without damaging substrates 24. how to remove contaminants from plating solutions, care and maintenance of solutions and filters 25. the importance of agitation, and various methods of achieving this 26. the jigging methods, construction of jigs and spacing of components, to give satisfactory deposits and maintain optimal productivity levels 27. how to carry out effluent treatment 28. the benefits of agitation and the importance of keeping the absorption of air into alkaline plating solutions to a minimum 29. the effects of contaminants in plating solutions and how to remove these 30. the extent of your own responsibility and whom you should report to if you have problems that you cannot resolve 31. how to access, use and maintain information to comply with organisational requirements and legislation |
Scope/range
Scope Performance
1. Finish materials by nickel and chromium plating, carrying out all of the following: 1. use the correct issue of process and related specifications 2. adhere to health and safety regulations, systems and procedures to realise a safe system of work 3. ensure that the equipment is correctly prepared for the nickel and chromium plating operations 4. ensure that meters and gauges are within their calibration periods, especially any pH measuring equipment 5. clean all tools and equipment on completion of the nickel and chromium plating activities 6. complete the production documentation (condition/pre-treatment of substrates, coating material preparation, equipment settings, confirmation of standard of finish) 7. leave the work area in a safe and clean condition 2. Carry out nickel and chromium plating on one of the following substrates: 1. mild steel 2. stainless steel 3. brass 4. zinc based die castings 5. plastics 6. other specific substrate 3. Use one of the following methods for locating and processing the components: 1. wiring 2. jigs 3. jigs with integral masking 4. specialised barrels (for chrome) 4. Measure and correct two of the following nickel and chromium process conditions: 1. basic constituents in either hexavalent or trivalent plating solutions 2. basic constituents in bright and semi-bright nickels 3. plating efficiencies 4. contaminants in plating solutions 5. pH of plating solutions 6. temperature of plating solutions plus two more from the following: 7. effectiveness of inhibition in acid pickling process 8. acidity and contamination levels in pickling solutions 9. total and free alkalinity of cleaners 10. effectiveness of rinsing 11. contamination levels in cleaners 12. temperature of cleaners 5. Identify and correct two of the following: 1. high level of trivalent chromium in a hexavalent chromium solution 2. metallic contaminants in trivalent chromium solutions 3. metallic contaminants in nickel solutions 4. organic contaminants in nickel solution 5. high sulphate levels in hexavalent chromium 6. Check the coated components during processing for two of the following: 1. plating efficiency 2. balance in hexavalent chromium solutions 3. throwing power 4. presence of metallic contaminants 5. brightener levels in nickels 6. presence of organic contaminants 7. Carry out three of the following plating activities: 1. make additions of salts safely to solutions 2. calculate brightener and other maintenance additions correctly 3. set and check ampere-hour automatic dosing equipment (where applicable) 4. prepare plating solutions from basic salts 5. carry out carbon treatments prior to processing 6. change and maintain filters 7. strip poorly applied coatings 8. Carry out one of the following quality control procedures: 1. corrosion resistance (neutral salt spray or copper accelerated salt spray as appropriate) 2. adhesion of deposit to substrate 3. thickness of multiple layers 4. brittleness of deposit 5. porosity of decorative nickel deposits plus one more from the following: 6. presence of chromium deposit 7. sufficient coverage of chromium deposit 8. presence of blisters 9. satisfactory levelling 10. satisfactory colour and brightness 11. presence of pitting 9. Check coatings applied to components by nickel and chromium plating comply with one of the following quality and accuracy standards: 1. military or aviation standards 2. current industry standards and codes of practice 3. international standards 4. company standards and requirements 5. customer standards and requirements |