Metal spraying or thermal spraying, is one of the most popular coating process. In this process, metal or ceramic is sprayed on the surface of other material or metal. In the process, the metal or material, which has to sprayed, is chosen from a wide list. Some of the uses of the this process, includes the following:-
1.Galvanizing has become outdated:- there was a time, when galvanizing was the prime technique used to boost the life and immunity of any metal. However, introduction of thermal spray, has reduced its popularity. The current available options are not only more effective, but also clean,and looks very attractive. Whereas, during galvanizing, there used to be distortion in the shape of metal structures.
2.Reduced cost: - Metal spray takes place at a much reduced temperature. This is the reason; it does not cause any distortion, and allows safe treatment of sealed hollow fabrication. Apart from that, size of the structure is not any criterion, the process can be carried out on the site itself, and when the equipments can be turned off, and moved to safe place, when they are not being used. Such advantages help in reducing a huge amount of money.
3.Film sets: - Different kinds of props are used in movies and film industry. All these props are made up of polystyrene. Although, easy to manage and develop, they are vulnerable of getting easily damaged. This is the reason, zinc and steel is sprayed on them, to make them more tough and robust. Such spraying not only intensifies the strength of the props, but also reduces their proximity of getting dent.
4.Wind Turbines: - These turbines are the main constituent of any wind based power generator unit. However, they are also quite prone to atmospheric corrosion. To improve their life, efficiency and performance, almost all leading manufacturer apply zinc or zinc/aluminum alloy spray over them. Doing that, not only significantly increases their life, but also improves their performance, and reduces the maintenance and care required.
5.Oil components and Structures:- Oil industry is one of the largest consumer of metal. The industry requires the metals to develop pipes, different structures, risers and many other things. All these things, they need in their industry for a host of activities. However, these structures always remains exposed to harsh chemicals and elements. This is the reason, they are either made to go through PTA welding or aluminum is sprayed on them.
Apart from the above discussed, there are many other metal spray applications. The most significant aspect of this process, is that it boost the efficiency of the metal component or structure. This is the reason, almost every metallic tool and equipment manufacturing organizations are now making the best use of the technique.
2. Oil Industry - Pipes, Risers and Structures
Oil industry pipes, risers and structures are often exposed to harsh elements and oil and gas platform structures benefit from the application of thermal sprayed aluminium (TSA). This is done using the arc or flame spray process, where the molten material is atomised by a cone of compressed air and propelled towards the pipes. This spray solidifies when it hits the surface to form a dense coating, which protects against corrosion for in excess of 20 years in the harshest of environments.
3. Bridges
There's usually heavy footfall or traffic over bridges so metal spraying them is ideal, as not only does it protects from corrosion - it also helps extend a bridge's life. The flame spray process, where the wire is fed by a driven roller system through the centre of an oxygen-fuel gas flame and is melted, is ideal for protecting bridges. This is proven to be the best protection from corrosion and can provide protection for up to 20 years to first maintenance.
4. Petro-chemical Plants
In the petro-chemical industry, Corrosion Under Insulation (CUI) - where accelerated corrosion can occur under wet insulation - consumes a significant percentage of maintenance budgets. By protecting against CUI, companies can move towards inspection-free and maintenance-free piping systems and significantly reduce maintenance costs. The spraying metal process is the ideal solution for the protection of refinery and process plant vessels, tanks and steel fabrications, as it's proven to be a very robust coating solution for protecting against CUI.
5. Structural Steelwork
The Burj Al Arab hotel in Dubai is one of the most famous steel structures that's been metal sprayed. In total, 10,000 m2 of steel work was arc sprayed, including the heli deck frame work, roof mounted mast and 6 diagonal support braces. The aluminium coating should protect the Burj Al Arab from corrosion for around 15 to 20 years, even in the harsh, coastal environment in which it's situated.
6. Seam Spraying Of ERW Tubes
Tubes are produced on a tube forming mill by Electrical Resistance Welding (ERW) the longitudinalruch seam. During the welding process, the heat generated destroys the external coating around the weld area. Unless the ERW seam is protected, this area will corrode. The ideal way to protect it is to spray the seam with a material that has similar corrosion resistant properties. This corrosion resistant tube has numerous uses, including domestic and garden furniture, car seat frames, parking barriers, balustrades and even car exhaust pipes.
7. LPG Cylinders
Metal spraying is used to protect LPG, propane gas or butane gas bottles against corrosion. Gas cylinders are often refurbisruchhed and, as part of that process, the surface of the bottles is grit blasted to prepare it prior to spraying with zinc. LPG cylinders are usually sprayed using the arc spray process.
8. Architectural Coatings
There are many creative architectural coating solutions for things like balcony parts, such as support columns, balcony decks and curved railings, and decorative window and door frames. If used externally, they will be subjected to the corrosive effects of the weather so need to be protected. Metal spraying is ideal for this, as being a cold process there is no risk of distortion or fettling, unlike with hot dip galvanising. There's also the opportunity to use different coatings, such as bronze or copper, to fit with the overall design scheme.
