Application of DC-Arc Plasma Coating

Transcription

1 Application of DC-Arc Introduction Application of Plasma Coating is nearly unlimited and is used in almost all sectors of industry; Table1. In many industries the quality of their products and the productivity of their technologies depend upon the quality and consistency of the thermal spraying maintenance of their production installations and equipment. Fields of application Repair and maintenance Wear Corrosion Thermal barrier Surface properties Specific properties Sector of application Heavy machinery Steel industry Oil, gas & chemicals Rubber & Tire Automotive Aircraft Energy Defense Textile Paper Printing Food processing Pharmaceutical Many more Principle applications are: To restore dimensions of a worn working machine part, most frequently of a revolving or otherwise movable part and\or its supportive counterpart. To harden the working surface of the static, rotating or otherwise movable machines parts and to increase their abrasion and wear resistance. To improve other engineering characteristics required from machine parts such as corrosion and cavitations resistance and resistance to higher service thermal load. Most of feedstock materials (metals, alloys, cermets, ceramics, carbides and composites), injected into the high temperature and velocity plasma stream, are melted and accelerated to impact onto whatever substrate, correctly prepared, in order to form a coating with good adhesion and required density which meet the customer requirements. Quality, reliability and reproducibility yet require a perfect control of the technology, high-performance equipments, consumable powders strictly selected, and skilled personnel and appropriated research and development resources. Copyright Plasma Jet Co 1 1

2 Sector of Application AIRCRAFT INDUSTRY Aircraft maintenance service would be impossible without plasma spraying technology. Over 30 different materials have been used for reparations and protection on different parts of an aircraft today. Combustion systems and gas turbine blades are most prominent parts that require strictly regulated reparation maintenance. AUTOMOTIVE INDUSTRY Piston rings (abrasion and wear) Synchronizing rings (abrasion and wear) Alternator household (electrical insulation) Breaks disks of sports car (friction and wear) Engine valves (corrosion, erosion and thermal insulation) Reparation of different worn working surface, e.g., cam and crank shaft METALLURGICAL APPLICATION Induction coil for high temperature ovens Cast moulds, Measure probe Oven burners Rolls of the annealing furnace High temperature support bearings CHEMICL INDUSTRY Machine parts (corrosion and erosion) Pumps household (corrosion and erosion) Sleeves (friction and anti-friction properties) Shafts of screw pumps THERMO POWER PLANT Burner (thermal insulation and oxidation protection) Pushing fans (erosion and corrosion protection) Static gas turbine (the hot gases corrosion) Valves for overheated steam (cavitations and corrosion) HYDRO POWER PLANT Gate valves (abrasion and cavitations) Turbine blades (friction and abrasion) Hydrodynamic bearings (antifriction) SHIPBUILDING INDUSTRY Engine s parts Parts working in water (corrosion and friction) MEDICINE Coatings to increase the surface of biomedical implants (Titanium and Titanium + Ca-hydrosiapatit) Copyright Plasma Jet Co Copyright Plasma Jet C 2 2

3 Acceptable Part Substrates: Steel Cast iron Stainless steel Aluminium Bronze Plastics, fibreglass, and carbon fibre materials Acceptable Part Configuration: Cylindrical Flat Open design fabrications More specific applications of Plasma Coating: Applications of protective coatings against: Corrosive atmosphere, Hot gas corrosion, Immersion corrosion Applications of coatings with specific properties such as: Diffusion barrier, Catalytic surface, Passive surface, Electrical insulating, Electrical conductivity, Ant-electrostatic coatings More information on thermal spray coating for corrosion protection (different types of corrosions) and thermal spray coating for wear resistance protection (different types of wear losses) can be found on and on several other web sites on Internet. Applications depend on feed stock available The enhanced quality and variety of feedstock powders is contributing significantly to the advancement of thermal spray technologies. Feedstock powder is usually 10 to 70µm, and sometimes even 150µm in diameter and is commonly carried by an inert gas into the emerging plasma plume. As many different powders are used by the thermal spray industry, they should be evaluated on a case-by-case basis to determine what particle size distribution and composition for individual product and its application is optimal. There are several hundred commercially available powders specially developed for the various spray processes. They can be classified as: metals and alloys, carbides, cermets, oxides, polymers and composites. A reduced list of the most frequently used representatives of those types of powders are given in the in Fig 1. Copyright Plasma Jet Co Copyright Plasma Jet C 3 3

4 Fig 1.Different types of powder materials used in Plasma Spray Coating Benefits of plasma coating Coatings are mechanically bonded to substrates that are often metallurgically incompatible with the substrate; e. g. materials with a higher melting point than the substrate. Components can be sprayed with little or no pre- or post-heat treatment, and therefore component distortion is minimal. Parts can be rebuilt quickly and at low cost, and usually at a fraction of the price of a replacement. By using a premium material for the thermal spray coating, coated components can outlive new parts. Thick coatings can be applied at high deposition rates. Thermal spray coatings may be applied both manually and automatically. Copyright Plasma Jet Co Copyright Plasma Jet C 4 4

5 Applications realized with the PJ-100 In Serbia & Monte Negro Aluminum made channel coated with ceramic for transportation of molten glass masse to the glass casting machines (Serbian Glass Factory, Paracin). Rock valve axis protected from cavitations in the overheated steam at 550 o C and pressure of 50 bars (Thermo Power Plant Kostolac) The engine crank shaft in the sport car (250 HP and 9,000rev/min) of Yugoslav champion Atanackovic. Reparation of the rotating shafts (10,000rev/min) use in the milk industry. For Italian market Surface protection on rollers used for homogenization of color pigments, in the paint manufacturing industry. Deposition of hard coating on the rollers made by carbon fiber/epoxy composite that are used in the paper industry. Four different materials were tested, wherein two of those materials with specific requirements were produced by an Italian company. Applications that have been considered but were not realized because of clients difficulties to go ahead in realization: Reparation of inner walls of a pair of hydraulic cylinders that support the rollers in the Cold Rolling Mill, the SARTID (USA - Serbia & Monte Negro Steel Mill, Smederevo). Protection of the rollers working surface in Tobacco Factory Bujanovac that are currently maintained by hard chroming technology by a Germany company. Reparation of the rotor bearings of a big screw compressor (1800mm in length) for the Copper Mining & Metallurgy Basin Bor. Outward protection of a pump O-ring ( ft) for Matroz Paper Factory in S. Mitrovica. Protection of a rotating disk, made of GS-17CrMo55 steel, from the coal dust Disk wieghts11, 000kg and is 8m in diameter, installed in one of Serbian thermo power plant s turbine. Protection of the G6-14 burner (weighting 560 kg) installed in the process of methanol production (Combustion of natural gas within the Texaco technology). Copyright Plasma Jet Co Copyright Plasma Jet C 5 5