Silver Plating Process at “Orao” in Bijeljina – Essential for Aircraft Engines, but Also in Demand by Other Companies
“Orao” a.d. Bijeljina, a company specializing in the overhaul and maintenance of aircraft jet engines, is well known for a range of processes carried out within its Electroplating and Chemical Protection Sector. One of these processes is silver plating, an electrochemical process used in this case to coat components made of heat-resistant steel, nickel-containing steel and other alloys. The primary purpose is to prevent galling and seizure of components, which are most commonly found on the rotor or in certain bearings of aircraft engines.
Stana Stanišić, Head of the Electroplating and Surface Protection Department at “Orao”, explained that during engine overhauls, silver coatings are applied to components made of nickel alloys, stainless steel, heat-resistant steel and high-strength structural steel, as well as to components made of copper and copper alloys.
“Silver plating is applied to prevent galling and seizure of components on the gear-tooth surfaces of shafts and pins, as well as to improve electrical contact at locations where reliable electrical conductivity is required. The silver plating process at ‘Orao’ is carried out in accordance with the technologies defined in the documentation of the Overhaul Business Unit, as well as in compliance with international standards,” Stanišić stated.
She emphasized that silver is an exceptionally good electrical conductor and that, in addition to the aviation industry, silver plating is also used in the maintenance of electrical power networks. For example, during the overhaul and maintenance of substations and transmission lines, copper and copper-alloy contacts may need to be silver-plated in order to ensure adequate electrical conductivity.
“Our sector currently employs five operators who are qualified and trained to work on the silver-plating line.”
From a technical standpoint, the process is not particularly demanding compared with, for example, hard chrome plating, which is one of the most complex processes in terms of employee training and qualification. However, silver plating is highly hazardous because operators work with cyanide-based solutions and must strictly comply with safety and occupational health requirements.
“In addition to carrying out silver-plating processes for our own internal requirements, particularly for the overhaul of aircraft turbojet engines, we are also open to cooperation with other companies from Europe and around the world that require silver-plating services,” emphasized Stana Stanišić.
The Electroplating and Chemical Protection Sector at “Orao” performs complex processes in accordance with high technological standards. Across seven mechanized processing lines, more than fifteen chemical and electrochemical processes are carried out on a daily basis, some of which are unique at the European and global level.
These processes include:
- Anodizing
- Chromating of aluminum and magnesium
- Nickel plating
- Silver plating
- Copper plating
- Cadmium plating
- Zinc plating
- Phosphating
- Black oxide treatment
- Hard chrome plating
- Lead plating
- Indium plating
Certain electroplating and chemical processes performed at “Orao” have been approved by renowned global aerospace companies, including Pratt & Whitney of Canada, as well as Collins Aerospace and General Electric of the United States.
