There are a wide variety of methods that can be used in metal finishing. The finishing of a metal is usually done after the metal has been formed. Any action that changes the surface of a metal work-piece in order for it to gain certain characteristics is called finishing. Finishing has many advantages for metal. For instance, it improves the following qualities: resistance against wear and corrosion, electrical resistance, electrical conductivity, tolerance to torque, hardness, resistance to tarnish and chemicals, solderability, ability to bond to rubber, and reflectivity and appearance. There are many different types of metal finishes: anodising, electroplating, electroless plating, and passivation.
Metal finishing facilities are meant to follow many federal regulations with regards to environmental air emissions and the disposal of hazardous waste. The US EPA Office of Air and Radiation regulates operations that involve the emission of metals and toxic materials into the air. Air emission controls installed at the facilities go on to have an impact on the wastewater. The solutions from the process of metal finishing as well as the wastewater are extremely toxic. Therefore, metal finishing facilities need to be aware of the hazardous waste regulations. Below, we provide some of the regulations to keep in mind at metal finishing facilities sourced from a report by the United States Environmental Protection Agency (US EPA)..
National Emission Standards for Hazardous Air Pollutants (NESHAPs), US EPA Office of Air and Radiation: There are technologies of air control that enable the mitigation of air emissions: wet scrubbers, for example. Emission directives for electroplating and anodizing chromium are tight. It is important to keep in mind, for instance, that perfluorooctane sulfonate-based fume suppressants are banned in any air pollution control devices. Platers are required to implement those management practices that lead to the reduction of airborne chemicals generated. The EPA has requirements regarding the reduction of air pollution of compounds of metals such as lead, chromium, manganese, cadmium, and nickel in nine metal fabrication and finishing source categories. If facilities are primarily engaged in any one of these nine source categories, the rules apply. The following operations are covered under these rules: dry grinding and dry polishing with machines, dry abrasive blasting, welding, dry machining, and spray painting.
Resource Conservation and Recovery Act (RCRA) Hazardous Waste Regulations, Office of Resource Conservation and Recovery (ORCR): Hazardous waste is generated by metal finishing facilities. Spent process solutions like plating baths and alkaline cleaners and metal finishing wastewater treatment residuals like filter cake and sludge are a part of the hazardous waste. Directives to dispose of this waste is provided by this act. EPA’s revision of the regulatory program made the regulations easier to understand. This is useful in facilitating better compliance and providing more flexibility in the management of hazardous waste. The revision also closes gaps in the regulations.
Other Environmental Directives: There are international environmental directives specific to states and countries that need to be complied with at metal finishing facilities, if they are looking to sell their products in those places. For instance, the EU limits the quantity and concentration of certain chemicals that are manufactured in or imported to their regions. It is important to consider all possible directives that could play a role when looking to sell products.
Customer Specifications: Depending on the industry, there might be strict specifications that need to be kept in mind. Aerospace, automotive, and defense industries usually have strict specifications that need to be followed for their plated parts. Facilities might be forced to use only specific chemicals and plating processes in order to meet these specifications. Therefore, these guidelines should also be kept in mind at metal finishing facilities.
At DiamondBrite, we specialize in a variety of architectural and ornamental finishes: #4 finishes, #6 and #7 finishes, #8 mirror finish, non-directional finishes, longitudinal finishes, and other custom finishes. We are committed to providing the highest quality of finishing services for the market, whether architectural or commercial.