PRODUCTS & PROCESSES
To achieve the required plating and finish , the manufacturer had been hand-masking and tank plating the components . Probably the most common of plating methods , tank plating has long been used for plating high volumes of parts .
The process works by submerging the components into a series of large tanks of plating chemicals . When only a specific area of a component needs to be plated , it must first be masked to protect the remainder of the part from the solution in each tank .
For these parts - measuring less than an inch in diameter with eight small holes in the stem that did not require plating - the masking process required for tank plating was inefficient . As well as being labor-intensive , the results were inconsistent , with scrappage rates as high as 25 %.
Working with SIFCO ASC , the manufacturer made the move to encapsulated plating .
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Custom tooling and seals were used to encapsulate the parts for the preparatory step , the nickel plate , and the gold plate . As well as dramatically reducing the cross contamination between each step , the new process offered state-of-the-art repeatability , even distribution and a higher throughput per hour .
What is encapsulated plating and how does it work ?
Originally developed by SIFCO ASC for the high-speed plating of components for the automotive industry , encapsulated plating combines the best of both tank and selective plating , offering a sustainable way to plate axi-symmetric parts with deep bores or recessed areas .
Using custom tooling combined with state-of-the-art , customized electrodes designed to match the complex geometry of the selected area , the part is encapsulated and sealed for coating . The plating solution is directed through a gap in the tooling , allowing it to flow over the part at high velocity and plate only the part and the electrode .
The use of custom all-in-one tooling rapidly deposits a precise thickness of metal on a selected surface of even the deepest bore . The optimized high solution flow velocity aids in removing hydrogen gas bubbles and replenishes the metal ions at the surface of the workpiece , providing a smooth and uniform finish .
Improved process control
As industries become subject to increasingly strict standards , both components and finished products must stand up to scrutiny . Ensuring process control , repeatability and traceability is key to ensuring that manufacturers meet exacting industry specifications .
For FAMAT , a leading manufacturer of aircraft engine casings , the ability to withstand friction , high operating temperatures and corrosion while also meeting process and quality control parameters was vital . Aerospace is an industry that is highly demanding when it comes to surface finishing performance requirements and it is rightly renowned in its robust standards for the manufacture and repair of high-performance equipment .
The company approached SIFCO ASC to improve the hardness of their casing grooves using selective anodizing . With process control and repeatability at the heart of their specification , encapsulated plating offered an ideal solution .
As a one-piece flow treatment , which uses the same tooling and parameters time and
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