Surface Treatment Sector

Creating a safe process

In surface Treatment applications such as galvanisation, plating, degreasing, pickling, coating/painting, and etching, many hazardous chemicals are used. Therefore, encapsulation and automation of the process are important from pre-treatment, surface treatment, and waste handling after treatment. Safe and reliable pumps and filters are important components in creating a safe process.

Process & Fluid examples

• Electrolytic zinc plating Copper, Nickel, Tin, Silver and Gold plating
• Alcalic zinc
• Zinc-iron
• Zinc-nickel
• Hexavalent Chromium-free plating
• Chromates/Passivation
• Acid zinc
• Chemical nickel
• Anodic coating
• Organic coating

Duties for Pumps & Filters

• Degreasing bath
• Pickling bath
• Alkaline bath
• Acid bath
• Electro-plating bath
• Waste from bath Drum
• Drum handling
• Filter press feeding

Galvanisation

Galvanisation is the coating process most used to prevent the corrosion of iron and steel. The process consists of coating the metal with a layer of zinc by submerging it in a bath of molten zinc at high temperature (about 450 °C). Galvanisation is achieved when the metal contacts the hot zinc, creating a metallurgical reaction that produces a series of zinc-iron alloy layers on the surface. The final product is a protective zinc coating that protects the iron or steel from harsh environments by preventing rusting. To secure the metallurgical reaction and achieve a quality coating, the surface of the metal must be chemically clean. The preparation of the surface is essential before galvanising, and types of contamination like grease and dirt are removed by a variety of processes.

Plating

The metal plating process involves creating a thin layer of metal (nickel, copper, chromium or other metal) that coats a substrate. Metal plating provides many benefits to products made from metal and other materials, such as enhancing appearance and inhibiting corrosion. The plating manufacturing process can be achieved through electroplating, which requires an electric current, or through electrolysis plating, which is included in an autocatalytic chemical process. In either case, the technique results in one or several of the following benefits:

• Improved corrosion resistance
• Decorative appeal
• Increased solderability
• Enhanced strength
• Reduced friction
• Altered conductivity
• Enhanced paint adhesion
• Increased magnetism

Degreasing

Degreasing covers a wide range of applications across almost every industry, particularly in wash bays for metals. In the process, degreasing chemicals are used to remove dirt, oil and other inorganic material from surfaces. Acid and alkali degreasers remove oils and other soils through aggressive chemical reactions. These are toxic acids that require safe handling and automation processes to avoid harm to workers and minimise the environmental impact.

Coating and Painting

Coatings provide two primary functions— decoration and protection — that are of considerable economic importance. Without coatings, product lives might be shortened drastically and many products would not even be marketable. Most of the remaining coatings, called “special purpose,” are used for miscellaneous applications such as traffic paints, vehicle refinishing, high-performance coatings for industrial plants and equipment, and protection of marine structures and vessels. These are usually applied outdoors in ambient conditions.

Etching

Chemical milling, photo etching or the metal etching process is a very specific and controlled method of manufacturing parts and components, as part of the large industry that is subtractive manufacturing. The etching process involves utilising temperature-controlled etchants, such as ferric chloride, which by eating away the design on the surface pf the metal previously printed. The designs are left exposed to the acid, while the rest of the metal is protected by a photoresist. The end result can produce items that look like they have been engraved or parts that are formed from one sheet of metal, no matter how intricate or complex the design.