Geared compressors

Figure 4-38. Ten-stage, integrally-geared compressor. (Source GHH-Borsig.)...

Figure 5-6. Flow diagram and schematic of an integrally geared compressor.

Figure 7-6. An integral geared compressor driven by a motor with an open drip-proof enclosure. The enclosure also includes 85dba sound attenuation. Courtesy of Elliott Company ...

Organic esters Diesters Polyol esters Turbine oils, mixing components with PAO Turbine oils, gear, compressor, hydraulic oils... 

FIGURE 3.30 Blowup of a three-stage integral gear compressor. (Courtesy of Cooper Industries.)... 

Alkylated aromatics are used as the base fluid ia engine oils, gear oils, hydrauHc fluids, and greases ia sub2ero appHcations. They also are used as the base fluid ia power transmission fluids and gas turbine, air compressor, and refrigeration compressor lubricants. 

In addition to their automotive use, PAO oils also find appfication in industrial and aircraft hydraufic fluids, gear oils, compressors, and environmentally sensitive appfications. They are also used in multipurpose greases for army, navy, nuclear, and industrial appfications. Expanding use has led to a growth rate of PAO production from 1985 to 1990 of 19% per year (28). 

Miscellaneous Commercial Applications. Dimer acids are components of "downweU" corrosion inhibitors for oil-drilling equipment (see Petroleum Corrosion and corrosion inhibitors). This may account for 10% of current dimer acid use (71). The acids, alkyl esters, and polyoxyalkylene dimer esters are used commercially as components of metal-working lubricants (see Lubrication). Dimer esters have achieved some use in specialty lubricant appHcations such as gear oils and compressor lubricants. The dimer esters, compared to dibasic acid esters, polyol esters and poly(a-olefin)s, are higher in cost and of higher viscosity. The higher viscosity, however, is an advantage in some specialties, and the dimer esters are very stable thermally and can be made quite oxidatively stable by choice of proper additives. 

Synchronous speeds are calculated by Eq. (29-10). Speeds above the limits given are obtained through step-up gears large high-speed centrifugal compressors are examples. Two-pole (3600 r/min at 60 Hz) synchronous motors can be built but are uneconomical in comparison with geared drives. 

Steel works conveyors, crushers, w agon tipplers, skid gears, furnace charges, bogie drives in bogie hearth furnaces, furnace winch drives, cranes, pumps, compressors and fans. 

Most ethylene plants operate continuously with the expanders operating at or near design conditions. If necessary, due to their unique design characteristics, radial inflow turboexpanders can accommodate a wide range of process conditions without significant losses in thermal or mechanical efficiency. Expanders may be loaded with booster compressors, gear-coupled generators, dynamometers, or other in-plant mechanical equipment such as pumps. In ethylene plants, turboexpanders are typically used in eitlier post-boost or pre-boost applications. 

A number of coupling options exist with motor drivers. The main gear is often equipped with a simple shoulder bearing, does not have thrust collars, and is connected to the compressor train with a solid coupling. Other manufacturers opt to use flexible couplings and conventional thrust bearings. 

In the case of nitrous acid plants, application of integrally geared process gas radial turbines and compressors are used in plants with capacities ranging from 120-600 t/day and higher. For air compression, up to three compressor stages are connected in series. To increase efficiency, the inlet temperature of the individual stages is reduced by using two external intermediate coolers. 

Figure 4-39. Integrally geared multistage compressor. (Source Demag Delaval.)...

The main power source is a 2,200 kW rated motor, which drives two high-speed pinions through integral gears. The first stage of the compressor operates at 17,900 rpm, while the second and third stages operate at 21,800 rpm. The unit is controlled by a local control system, but operators can also monitor the operating parameters from the plant control room. 

API Std 672, Packaged, Integrally Geared Centrifugal Air Compressors for Petroleum, Chemical, and Gas Industry Services, 3rd Edition, September... 

For gas turbines, especially the more advanced high-temperature gas turbines, the oil of choice should be synthetic oil, since synthetic oils have a high flash point. Gas turbine lubrication systems should be run for about 20 minutes after shutdown since maximum temperatures are reached after 10 minutes of shutdown especially in the bearing area. Most gas turbines are also on turning gear to avoid sagging in the shaft. Mineral oils can be used for the compressor. It is not uncommon to have two types of oil in a petrochemical plant. Mineral oil costs much less than the synthetic oil. 

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