New award-winning technology for electroplating of metal parts can—for the first time—eliminate the century-old, hazardous, tedious, error-prone step of hand masking, researchers say.
The new option—known as “No-Mask Conforming Anodes”—was pioneered by a team of industry and Department of Defense participants, led by the National Center for Manufacturing Science (NCMS).
Video images: NCMS
|Traditional electroplating generates “mountains” of toxin-saturated used maskant, NCMS says. The new technology creates zero toxic waste, researchers say.|
The team consisted of depot engineers from the Corpus Christi Army Depot (CCAD), the Fleet Readiness Center (FRC) Southwest, and Advanced Tooling Corporation (ATC). The project was funded through the Commercial Technologies for Maintenance Activities (CTMA) program, a DoD-supported NCMS initiative.
‘Nothing Less Than Astonishing’
“The results of this project are nothing less than astonishing,” said Bill Chenevert, NCMS Program Manager for the project, which has been underway for several years. “We took this 100-year-old process and gave it a technologically advanced overhaul, saving money, time and the environment.”
The development has transformed a “massively inefficient process” that “burns through enormous amounts of power” and “generates mountains of toxic waste” into a “zero waste system,” the team explains in a video demonstrating the technology.
According to NCMS, the pilot project:
• Reduced pre-plating part preparation by 95%;
• Reduced plating time by 45%;
• Increased plating tank capacity by 50%, improving overall throughput; and
• Yielded $2.2 million in immediate annual savings from the pilot parts alone.
Given the tens of thousands of metal parts it electroplates, the Defense Department may save as much as $50 million in the first three years, researchers said.
Dangers and Waste
“The basic techniques involved in electroplating have not changed substantially in over 100 years,” NCMS notes in an article on the project in Digital Manufacturing Report. “You carefully hand-mask areas of the part you wish to protect from plating, and dip the whole thing into an electrified tank for several hours.”
The process is hugely time-consuming, prone to error, involves highly toxic plating baths, and creates vast quantities of toxic waste—multiplied by the thousands of vehicle, aircraft and machinery parts exposed to corrosion and wear in military and manufacturing applications.
The goal of the no-mask project was to eliminate masking labor, achieve faster plating times, improve uniformity of deposits, and minimize the hazards involved.
“Masking used to take hours and hours,” said Randy Taylor, president of ATC. “It was subjective, from one person to the other. It was a lot of operator error; different interpretation of dimensions could result in variances that were unacceptable.”
How it Works
In lieu of hand masking, the team developed no-mask air- and liquid-tight conforming anodes that are custom-made for the part being plated. An acid-resistant PVC fits tightly around the part.
The tooling incorporates the anode configured to the specific part shape, which researchers say improves the speed and uniformity of the metal deposit by ensuring optimal anode placement for each part, regardless of geometry.
|The part is fitted with an air-tight, liquid-tight conforming anode custom-made for the part being plated.|
Areas to be plated are exposed to the solution and anode; the rest of the part does not electrically interact with the plating process.
No-mask anodes are also designed to minimize hydrogen bubbling; they can even be operated outside a plating tank, with plating fluid pumped through the tool at high speed, NCMS says.
The custom-made anodes are fully reusable, eliminating the hazardous waste from toxic-saturated maskants used in the conventional process. The process also minimizes the risks of hydrogen embrittlement, a major source of metal fatigue and damage, the team says.
‘Great Idea’ Winner
The process will not eliminate electroplating, which is “here to stay,” NCMS reports. “We need this technology.” But the advance will “bring it into the 21st century.”
The project won the prestigious “Great Ideas Competition” in November at SAE’s 2011 DoD Maintenance Symposium and Exhibition in Fort Worth, TX. The annual symposium brings together thousands of government and industry representatives to exchange ideas to improve maintenance practices and procedures.
Watch the video.