Thrust loads

An unsteady ain-flow unbalance that alternates between inlets can set up an alternating thrust pattern which can be very damagiag to beariags designed for low thrust load. Mechanical vibration and elastic deformation problems and diagnostic techniques for stmctural iaadequacies ia fan design are discussed ia Reference 16. 

Thrust Bearings Turboexpanders often have process upsets or ice plugging or the hke, which can cause serious thrust-bearing load variations. In applications above 506.6 to 1013.2 kPa (75 -148 psi), the best available thrust bearing usually is insufficient to protect against such high thrust loads. Various indicatious, such as the differential... 

The motor carries and supports any axial thrust by the pump (hydraulic or mechanical). The motor on these pumps can be fitting with precision rolling element bearings, either angular contact, spherical rollers, or pillow blocks inclined depending on the thrust load and velocit of the shaft. 

These bearings have two rows of balls and they can handle some shaft misalignment. The axial or thrust loading is limited. 

These are single row ball bearings capable of handling extreme axial or thrust loads in one single direction only. They are generally mounted in pairs to handle any opposite axial/thrust loads. 

This bearing is best suited to handle radial loads. It doesn t work well with axial/thrust loads. This bearing is popular in electric motors. 

These bearings are good handling extreme axial / thrust loads in one single direction only. 

The reaction turbine, shown schematically in Figure 2-2, is generally more efficient. In its primary (stationary) nozzles only half the pressure energy of the gas stream is converted to velocity. The rotor with a blade speed matching the full-jetted stream velocity receives this jetted gas stream. In the rotor blades the other half of the pressure energy is used to jet the gas backward out of the rotor and, hence, to exhaust. Because half the pressure drop is taken across the rotor, a seat must be created around the periphery of the rotor to contain this pressure. Also, the pressure difference across the rotor acts on the full rotor area and creates a large thrust load on the shaft. 

The Automatie Thrust Balanee System is a dynamie adjusting system. Hydrodynamie pressure at the thrust bearing faee, an indieation of thrust loads, is eontinuously monitored and fed to either side of a piston, whieh, in turn, adjusts the pressure aeting behind the eompres-sor wheel. 

Thrust loads on die bearings Seal gas pressure and flow Lube oil pressure... 

When combining compressors, expanders, and turbines, the speeds, thermal expansions, and thrust loads on shaft systems exist at different magnitudes and directions. These must be managed and accommodated with skill and experience. 

Increased energy across the rotating blades, which means a higher pressure drop across the rotating blades, thereby increasing the thrust loading. 

Figure 6-10. Maximum thrust loads with pressure upsets at the compressor discharge.

The system eharaeteristies of the entire train must be known so that the seleetion of the gear will be proper. The major points affeeting the system are (1) eouplings, (2) vibration, (3) operation eonditions, (4) thrust loads, and (5) mounting type. 

Thrust loading or thrust-bearing metal temperature... 

Other items unique to steam turbines that must be considered are water carryover and fouling. Carryover can leave deposits on the blading, causing loss in performance and increased thrust loads. If carried to an extreme, thrust bearing failure could occur. If a large amount of water is carried over as a slug of liquid, catastrophic failure can occur. 

Deep grove ball bearing high speed and high precision, average radial and thrust load excellent automobiles, cutting tools, water pumps, agricultural machinery... 

Self-aligning ball bearings supporting radial and thrust load where shaft and housing are subject to misalignment excellent rubber mixers, oil field drilling rigs, vertical pumps... 

Angular contact ball bearings average speed and support of radial and thrust load fair orbital sanders, food-processing machinery... 

Thrust ball bearings support only thrust load good autombile clutches, gauges and instruments... 

Spherical roller bearings support of radial and thrust load, expecially when the shaft is long excellent paper mill machinery, air compressors, speed reducers, cranes... 

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