High speed engines

For vehicles, special attention is most often focused on the knocking potential encountered at high motor speeds in excess of 4000 rpm for which the consequences from the mechanical point of view are considerable and lead very often to mechanical failure such as broken valves or pistons, and rupture of the cylinder head gasket. Between RON and MON, it is the latter which better reflects the tendency to knock at high speeds. Conversely, RON gives the best prediction of the tendency to knock at low engine speeds of 1500 to 2500 rpm. 

Uses. Indium s first commercial use was in the production of dental alloys (see Dental MATERIALS), but its first significant use was in the production of bearings for heavy-duty and high speed service (see Bearing materials). The advent of jet engines has reduced this use, but indium is still used in high performance engines. 

Technical data. Fundamentals of High Speed Dispersion, Myers Engineering Inc., BeU, Calif. 

The Stratford Engineering Company s (Kansas City, Missouri) continuous SO organic mist sulfonation uses a high speed atomizing rotor to horizontally disperse the organic feedstock stream impinging on the reactor walls in the presence of SO gas to effect sulfonation of petroleum feedstocks (290). 

Sohre, J., Operating Problems with High-Speed Turbomachinery—Causes and Correction, 23rd Annual Petroleum Mechanical Engineering Conference, September 1968. 

Sohre, J., Reliability Evaluation for Trouble-Shooting of High-Speed Turbomachinery, ASME Petroleum Mechanical Engineering Conference, Denver, Colorado. 

For most of the rotary compressors in process service, the driver is an electric motor. Compressors in portable service, however, particularly the helical-lobe compressor, use internal combustion engines. Many of the rotary compressors require the high speed that can be obtained from a direct-connected motor. The dry type helical-lobe compressor is probably the main exception as the smaller units operate above motor speed and require a speed increasing gear which may be either internal or external (see Figure 4-1). The helical-lobe compressor is the most likely candidate for a driver other than the electric motor. Aside from the portables already mentioned, engines are used extensively as drivers for rotaries located in the field in gas-gathering service. Steam turbines, while not common, probably comprise most of process service alternate drive applications. 

High-speed units are typically engine or electric motor driven, although turbine drivers have also been used. Engines or turbines can be either natural gas or diesel fueled. By far the most common driver for a high-speed compressor is a natural gas driven engine. 

High-speed engines are not as fuel efficient as integral engines C. OO to 9,000 Btu/bhp-hr). 

As previously discussed in this chapter and in Chapter 10, reciprocating compressors are generally classified as either low-speed (integral) compressors or high-speed (separable) compressors, API has provided a standard and specification for each type of compressor to help the user and the facility engineer provide reliable compressor installations. 

Pressure-volume curve illustration for a turbocharged and direct-injected high-speed heavy-duty four-stroke diesel cycle engine. 

Note in Figure 4 that in a high-speed engine, the... 

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