Turbine components

Plating and Coatings. Thin surface coatings of platinum and platinum alloys are used as decorative finishes and in critical appHcations where it is necessary to provide finishes resistant to corrosion or high temperature, eg, coatings on jet-engine turbine components (258). Compounds used in the electro deposition of platinum are based on Pt(Il) and Pt(IV) and include H2[PtCl3] and its salts, eg, Pt—P—Salt, [Pt(NH3)2(N02)2] H2[Pt(S04)(N02)2] ... 

The injection of coolant air in the turbine rotor or stator causes a slight decrease in turbine efficiency however, the higher turbine inlet temperature usually makes up for the loss of the turbine component efficiency, giving an overall increase in cycle efficiency. Tests by NASA on three different types of cooled stator blades were conducted on a specially built 30-inch turbine cold-air test facility. The outer shell profile of all three blade types was the same, as seen in Figure 9-24. 

High-temperature gas-turbine components. Diesel-engine components. 

Alloy coating of turbine components by electron-beam evaporation and sputtering. 

Most metals and many refractory compounds can be thermal-sprayed. Applications include coating of gas-turbine components for aircraft and industrial use, components of steam turbines and diesel engines, components for the oil and gas industry, paper and pulp industry, and chemical processing industry. 

The wind turbine-generated electricity is already cost competitive (5-9( / kwh) with natural gas-based electricity and in some locations also with nuclear- or coal-based electricity. During the last few years, the cost of wind turbines in the United States has been increasing because the price of commodities and the value of the Euro have been rising (most turbine components are imported from Europe). 

In a number of renewable energy processes, information on the linear or rotational position of solar collector or wind turbine components is needed to control and optimize the operation of these processes. 

Trace elemental analysis can also be used to indicate the level of contamination of middle distillate fuels, e.g. turbine fuels. Metal contamination can cause corrosion and deposition on turbine components at elevated temperatures. Some diesel fuels have specification limits to guard against engine deposits, however they sometimes employ Mo or Ni as a catalyst for the refining process which eventually ends up in the finished products. There are several sources of multi-elemental contamination in naval distillate fuels. Sea water is pumped into the diesel tanks as ballast to immerse ships and submarines. Some oil transport ships have dirty tanks and contamination and corrosive products can also come from piping, linings and heat exchangers. 

In other contexts, the turbine head is sometimes written as /it = — (ftshaft — ftFriction)T, where the subscript T refers to the turbine component of the contents of the control volume only. The quantity /it is the actual head drop across the turbine and is the sum of the shaft work head out of the turbine and the head loss within the turbine. 

Cobalt-based alloys, in both wrought and cast forms, have also been developed for high-temperature applications such as gas turbine components, furnaces, and kilns. Alloy 25 (55Co-20Cr-10Ni-15W) (UNS R30605) is an example. Manufacturers are usually consulted in selecting these alloys. 

G. Whal, W. Nemetz, M. Giannozzi, S. Rushworth, D. Baxter, N. Archer, F. Cemuschi and N. Boyle, Chemical Vapor Deposition of TBC An Alternative Process for Gas Turbine Components, Trans. ASmm, 520-524 (2001). 

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