Bearing temperature control

Improved sensors allow computer monitoring of the system for safety and protection of the equipment from damage. Sensors include lubrication-flow monitors and alarms, bearing-temperature sensors, belt scales, rotation sensors, and proximity sensors to detect ore level under the crusher. The latter prevent jamming of the output with too high an ore level, and protect the conveyor from impact of lumps with too low an ore level. Motion detectors assure that the conveyor is moving. Control applied to crusher systems including conveyors can facilitate use of mobile crushers in quarries and mines, since these can be controlled remotely by computer with reduced labor. 

Any of the above reasons tnay result in noise and an increase in temperature and must be corrected. Critical installations such as a refinery, a petrochemical plant, a chemical plant or a petroleum pipeline may require special precautions and control to avert any excessive heating of the bearings, which may become fire hazards. For these installations, bearing temperature detectors with a relay and alarm facility may also be installed in the control circuit of the switching device to give warning or trip the motor if the temperature of the bearing exceeds the preset safe value. 

API Std 614 Lubrieation, Shaft-Sealing, and Control-Oil Systems for Speeial-Purpose Applieations API Std 670 Vibration, Axial-Position, and Bearing-Temperature Monitoring Systems ASME BPV Seet 11 Materials... 

Temperature control of the magnetic bearing housing environment is critical to safe operation of turboexpanders. Atlas Copco-Rotoflow has developed several schemes to monitor the bearing housing temperature and maintain it at a safe level. 

Figure 6-9. Pressurized bearing housing temperature control.

Controls. Request diagram of shutdown and alarm for over- or under-pressure, over-speed, high bearing temperature, lube oil system. 

When using a temperature-controlled oven, the bearings should be left in the oven long enough to heat thoroughly, but they should never be left overnight. 

An unusually extensive battery of experimental techniques was brought to bear on these comparisons of enantiomers with their racemic mixtures and of diastereomers with each other. A very sensitive Langmuir trough was constructed for the project, with temperature control from 15 to 40°C. In addition to the familiar force/area isotherms, which were used to compare all systems, measurements of surface potentials, surface shear viscosities, and dynamic suface tensions (for hysteresis only) were made on several systems with specially designed apparatus. Several microscopic techniques, epi-fluorescence optical microscopy, scanning tunneling microscopy, and electron microscopy, were applied to films of stearoylserine methyl ester, the most extensively investigated surfactant. 

Fig. 35. Schematic diagram of the rotating-cylinder reactor. 1, thermometer 2, temperature controller 3, housing 4, reactor inlet bolt 5, stirrer 6, temperature sensor 7, bearing 8, temperature sensor wire leads 9, stirrer shaft belt 10, stirrer motor 11, reactor holder 12, reaction chamber 13, water jacket inlet 14, O-ring 15, volume sensor 16, volume sensor wire leads 17, rotating chamber belt 18, rotating chamber motor 19, base place 20, reactor outlet bolt 21, water jacket outlet. (Reprinted with permission from Chem. Eng. Sci. 43,2025, J. H. Kim, E. D. Sudol, M. S. El-Aasser, J. W. Vanderhoff, Copyright 1988, Pergamon Press pic.)...

Figure 19.8 Rotary kiln reactor. 1 thermometer 2 bearing 3geartransmission 4electric furnace 5 rotary kiln 6 temperature controller 7 seal 8 tube condenser 9 filter 10 total flow meter 11 computer 12 gas sampling device 13 tar reservoir 14feed and discharge opening 15 electric motor [16]. (Reproduced with permission from Elsevier)...

This section reviews NMR studies of phase transitions in minerals with the goal of illustrating the types of information that can be obtained from NMR spectroscopic data. Most of the studies discussed below do not bear directly on the transition mechanism, but, rather, focus on the temperature dependence of the structure above and below the transition and on the nature of the disorder (static or dynamical) in apparently disordered phases. Information on the transition mechanism requires data very near the transition temperature, whereas precise temperature control is difficult with typical commercial MAS-NMR equipment. This section concentrates on interpretation and structural/dynamical implications of NMR data. For more detailed descriptions of the transitions and the relationship of the NMR results to other experimental techniques, the reader should consult the original papers, or other chapters in this volume. 

Couples Purposely Insufficiently Immersed-— It is frequently desirable purposely to immerse the couple to an insufficient depth. In many processes the furnace is operated at such a high temperature that a thermocouple or protecting tube cannot withstand the severe conditions to which it may be subjected. In this case the couple may be immersed only part way through the furnace wall, or to a distance flush with the inner wall of the furnace. The temperatures indicated by couples installed in this manner are always lower than those of the furnace interior, but they bear a fairly definite relation to the temperature of the furnace, and hence the method is satisfactory for temperature control and reproduction of furnace conditions from day to day. 

As in all microfabrication processes, the cleanliness of the substrate is very critical for the silicon oxidation process. As discussed above, the crystalline orientation will influence the oxidation rate of silicon dioxide. There are other operational parameters that will affect the oxidation rate of silicon. This includes the dopants in silicon, the trace amount of water, the concentration of Cl-bearing species, the temperature control, and its profile. Extensive assessment of each parameter on the growth rate and the quality of the Si02 layer on silicon can be found in microfabrication related literature elsewhere. ... 

Bearing life depends critically on temperature therefore, bearing temperature is often monitored and, if necessary, cooling water is controlled. Also, accceptable bearing life is only obtained with proper lubrication. Larger machines are equipped with automatic lubrication systems, the correct function of which is monitored. 

Austenitic stainless steels resist oxidation by either oxygen-bearing or sulfur-bearing process streams. Austenitic stainless steel pipe is not foolproof simply because it has corrosion resistance. Many plant operators are too optimistic, feeling that tight temperature controls are unnecessary with austenitic stainless steels. If... 

Fig. 12, Apparatus for the preparation of 1,2-dicarbaclovodo-decarborane(12) (BioCjHu). (A) acetylene cylinder (B) nitrogen cylinder (C) l-l. trap (D) three 500-ml. round-bottomed flasks in series, equipped with extra coarse gas dispersion tubes and filled no more than half full with concentrated sulfuric acid (E) l-l. trap (F) column containing potassium hydroxide and anhydrous calcium sulfate (G) 1 -1. trap (H) extra-coarse gas dispersion tube (I) l-l, round-bottomed flask fitted with 35/25 standard socket Joints (J) water-cooled stirrer bearing (K) thermometer well (L) automatic temperature-control device (M) spark-free stirring motor (N) water-cooled condenser (O) Dry Ice-cooled condenser (P) 125-ml, trap (Q) 125-ml, mineral-oil-filled bubbler (R) gas exit port.

Steam turbine used for the generation of electricity Turbine overspeeding [load disconnection suddenly] /[trip throttle valve stuck] /control valve fault//[extrac-tion valve fault]. Bearings damaged" [turbine overspeeding] /[lube oil] /exces-sive vibration/no lube oil/bearing temperature too hot/insuffident oil because of dogged lines/flow of parasitic currents. 

The EMC directive allows CE marking of components that (1) have an intrinsic function and (2) are sold to the end user, but not when sold to manufacturer s or assemblers. Some components may bear CE marking under the EMC directive. Examples of components include personal computer circuit cards, computer disk drives, PLCs, stand-alone power supplies, electric motors (except induction), and electronic temperature controls. 

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