Capacity loading

Fatigue tests were performed under load control mode on a Schenck horizontal fatigue testing machine with hydraulic grips and a maximum load capacity of 25 kN. Tension-tension constant amplitude fatigue tests were carried out at three stress levels 60% a , 70% Cu and 80% a at two different stress ratios R = 0.1 and R = 0.5. The test frequency was kept constant (f = 3 Hz) for all the tests. 

Wide range of viscosity ia commercial petroleum oils is illustrated by the representative types listed ia Table 3. Despite this range, the largest proportion of oils are ia the 25-75 mm /s at 40°C viscosity range. Oils ia this range combine generally adequate hydrodynamic load capacity with low power loss, low volatiUty, and satisfactory low temperature properties. 

Viscosity Glassifications. The general ISO iatemational viscosity classification system for iadustrial oils is given ia Table 4 from ASTM D2422 (American National Standard Z11.232). For high speed machines, ISO viscosity-grade 32 turbiae and hydrauHc oils are a common choice. ISO grades 68 and 100 are appHed for more load capacity ia slower speed machines where power loss and temperature rise are less of a question. 

Ester fluids are modified with additives in much the same manner as petroleum oils. They are stabili2ed with an oxidation inhibitor, eg, 0.5 wt % phenothia2ine. Improved load capacity for gears and rolling bearings in aircraft engines is provided by 1—5% tricresyl phosphate. Zinc... 

Various other soft materials without the layer—lattice stmcture are used as soHd lubricants (58), eg, basic white lead or lead carbonate [598-63-0] used in thread compounds, lime [1305-78-8] as a carrier in wire drawing, talc [14807-96-6] and bentonite [1302-78-9] as fillers for grease for cable pulling, and zinc oxide [1314-13-2] in high load capacity greases. Graphite fluoride is effective as a thin-film lubricant up to 400°C and is especially useful with a suitable binder such as polyimide varnish (59). Boric acid has been shown to have promise as a self-replenishing soHd composite (60). 

Liquid metal selection is usually limited to the lower melting point metals in Table 15. Figure 17 shows that Hquid metal viscosity generally is similar to water at room temperature and approaches the viscosities of gases at high temperature. Hydrodynamic load capacity with both Hquid metals and water in a bearing is about 1/10 of that with oil, as indicated in Table 2. 

Material strength is but one factor ia determining maximum load that can be carried by a beating material. Load capacity is equally related to design details, lubrication, and general appHcation experience. 

The use of an extractant depends on loading capacity, extraction rate, pH range, and the cost of the reagent and the diluent. Loss of the extractant must be minimised because of its high cost. Organic losses to the aqueous phase are also undesirable because of the deleterious effect on cathode deposits. Advances in SX—EW processes are described in Reference 38. 

Combiaatioa soak-and-electrocleaner products are touted for use whea aormal soak cleaner is too much and a normal electrocleaner is too Htfle. These combination cleaners are often electrocleaners with additional surfactants. The results are often hard-to-tinse electrocleaner or a low capacity soak. The term heavy-duty, often used to describe cleaners, can refer to high caustic content or to good soil-removing, high soH-load capacity. 

Bearing type Load capacity Suitable direction of rotation Tolerance of changing load/speed Tolerance of misalignment Space requirement... 

Low power usage Very long life No Oil required Low system weight Reduced fire hazard Vibration sensors built-in Small load capacity Large size Higher investment Requires mechanical backup for power interruptions New technology Possible rotor-d3ntiamic problems... 

Higher harmonic contents may magnify the harmonic currents and affect the loading capacity of the line. 

Journal bearing length (based on an assumed load capacity)... 

While protecting the compressor from surge is the most compelling control problem, it is not the only requirement. The compressor throughput must be adjusted to match its load. Capacity control interacts with surge protection, which reduces the effectiveness of the antisurge control system if they are not decoupled. 

Figure 13-11. Journal bearing load capacity versus minimum film thickness and eeeentrieity ratio.

BEARING TYPE LOAD CAPACITY SUITABLE DIRECTION OP ROTATION TOLERANCE OP CHANGING LOAD/ SPEED TOLERANCE OF MISALIGNMENT SPACE REOUIRMENT... 

Mach number, 26, IHO, 42 effect on axials, 23 L rotor tip, 100 Magnetic bearings, 204-8 air gap, 207 auxiliary bearing, 207 electromagnets, 205 laminated sleeve. 2U load capacity, 206 sensors, 206... 

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