By: Bilal Said, Chief Engineer , Eaton Corporation
The Coating Certification Process
Meeting the Joint Industry Project’s (JIP) “Guideline For Qualification Of Wear And Corrosion Protection Surface Materials For Piston Rods” through the joint industry standards 3247 and 3295 is the “gold standard” for Highly Corrosion-Resistant Alloys (HCRA). Eaton’s recently completed DNV certification of its Eatonite™ laser cladding as an HCRA provides an example of how the process works. Eaton started by performing extensive powder coating and application technology testing and analysis to identify the combination that optimally addressed customer requirements. Results were evaluated for robustness of cladding processes, corrosion resistance, coating hardness, ductility, process control, and metallurgical evaluation. Most of the pre-evaluation work was done in conjunction with the DNV laboratories in Høvik, Norway, and Columbus, Ohio. Through this process, Eaton developed its own exclusive powder and proprietary laser application processes to optimize cladding performance. The DNV certification was divided into three key phases. In the first phase, DNV reviewed the background documentation related to the technology and the manufacturing procedure specifications. As a part of the certification basis, a critical parameter list was developed. Typical documentation included • design basis including description of the technology, functional limitations, and main data,
• • • • • • •
reliability targets and acceptance criteria, reference of applicable codes and authority requirements; principles of storage, transportation, installation, commissioning, operation, maintenance, and abandonment; interface requirements; environment; functional loads; principles of manufacturing and quality assurance; data sheets for chemical pre-treatment products and masking material where applicable; and coating applications (including control of essential process parameters and instrument settings).
The purpose for this phase was to understand and review the documentation of the critical parameters and overall certification plan, and identify key challenges and uncertainties. The second phase of the certification process consisted of on-site audits of the coating procedure during the manufacturing and finishing process. During the onsite audits, a review of the quality control measures and acceptance criteria for the finished Eatonite clad coating was conducted. The purpose of this phase was to ensure that the coating tested during the certification was representative of the metallic cladding. The final phase confirmed that the functional requirements and target reliability/functionality as stated in the guideline can be met through the battery of prescribed tests per JIP 3247. Eatonite successfully completed all three phases and was certified as the
first, and to date the only, cylinder coating to fulfill the “Guideline For Qualification Of Wear And Corrosion Protection Surface Materials For Piston Rods.” In practical terms, that means the coated cylinder rods deliver the mechanical performance of traditional SAE 4130 steel piston rods, combined with the corrosion resistance expected for materials like Inconel 625, giving customers the best attributes of both materials. The involvement of international organizations like DNV working cooperatively with industry leaders promises a new generation of HCRA coatings. Corrosion may be an inevitable natural process, but new materials and technologies like Eatonite are giving engineers and end users improved tools for the fight to control it. For more information, visit www.eaton.com
FIG. 3: Close-up view of laser coating of a cylinder rod
Endurance Assurance
• Offering the Industry’s Smallest Servovalve • Hydraulic and/or Pneumatic Models for Every Application • Fast, Linear Dynamic Response • Rugged and Dependable – Shock, Vibration and Thermal Rated • Here Today, and Engineered for Tomorrow • Performance, Reliability, Sustainability
Meet challenging design requirements by using servo technology engineered to enable ever-greater achievements. That’s the kind of longevity and endurance assurance you can count on when you specify Woodward servovalves and actuators for your motion control applications. Increase productivity, reduce maintenance, and make a responsible choice for the future. Look to Woodward for solutions today and no sacrifice tomorrow.
Take Control with Woodward 25200 W. Rye Canyon Road, Santa Clarita, CA 91355 (888) 659-4229 www.r-ddv.com
www.ifps.org | www.fluidpowerjournal.com
Circle 240
Tech Directory 2011
11