Balancing device

This equation can be used for an orifice plate introduced into pipework as a measuring, throttling or balancing device, and for a jet discharging gas into the injector of a burner at atmospheric or sub-atmospheric pressure. 

Design arrangements for reduced-temperature secondary systems (sometimes referred to as injection circuits) include fixed provisions for minimum dilution rates. Conventional system-balancing devices with three-port automatic modulating valves to regulate mixed water temperatures and, hence, heat output are used. Automatic safety controls must prevent excessive temperatures occurring in the coil circuits, as floor fabrics or finishes could be damaged very rapidly. 

Devices for converting electrical signals to other, nonelectrical signals and effects. This group includes electroosmotic micropumps, different types of balancing devices, color indicators, and so on. 

Interstage bushings and thrust-balancing devices on multistage pumps may have the manufacturer s standard clearances, provided these clearances are stated as exceptions to this standard (see 2.6.4.2) in the proposal and are approved by the purchaser. When the manufacturer s standard clearances are based on material combinations exhibiting superior wear characteristics, supporting data shall be included in the proposal. 

EXAMPLES Wear rings, interstage bushings, balancing device, throat bushing, seal faces, bearings and gaskets. 

Most of the active balancing devices, specifically developed for the DLC, turn out to be a subgroup of the passive systems. The cell voltages are monitored by a survey equipment. When one of these cells reaches or overcomes a preset threshold level, a bypass is activated by an interrupter (transistor). This opens a path for the current which may flow in a dissipative resistor [56,57], This method limits the self-discharge amplitude to a minimum value because the system is working only when necessary. 

The oxygen accumulator is a simple pressure balancing device, and is sized according to the total volume of tubing and other components on the hydrogen side. It is an easy and inexpensive way to balance the output of each side of the system within a certain range. The disadvantage is that the volume of liquid in the bubbler affects the pressure balance, so, if an accumulator is used, keep the bubbler liquid levels near the level used to calculate the size of the accumulator. 

A major advance in technique was made by Curtis, Scheibli, and Bradley (49) in 1950 when they employed a jolly balance device (the Shell Thin Film Evaporometer) to follow weight loss of solvent when applied to a filter paper cone. The New York Paint and Varnish Production Club made a detailed study of the Evaporometer (50), made some modifications in the method, and concluded that the instrument gave results that were repeatable within one laboratory, reproducible at different locations, and in general provided better results than alternative methods investigated. The instrument has been improved over the years and now is produced in a highly automated model (51). 

Figure 4.34. Balancing device. [Adapted from Week, D. Cotter, J. E. E., US Patent 7,344,488,...

The U-tube densitometer, a beam-balance device, is also a final product density sensor. Solids can settle out in the measuring tube, causing calibration shifts or plugging. 

Another type of heat exchanger is a kettle reboiler. Reboilers are energy-balance devices attached to distillation columns to help control temperature. Reboilers have two basic designs ... 

In the absence of carbon monoxide in the sample cell, the two sensor chambers are heated equally by IR radiation from the two sources. If the sample contains carbon monoxide, however, the right-hand beam is attenuated somewhat and the corresponding sensor chamber becomes cooler with respect to its reference counterpart. As a result, the diaphragm moves to the right and the capacitance of the capacitor changes. This change in capacitance is sensed by the amplifier system. The amplifier output drives a servomotor that moves the beam attenuator into the reference beam until the two compartments are again at the same temperature. The instrument thus operates as a null balance device. 

The behaviour of polymeric polypeptides at the air/water interface was studied. Relative hydrophobicity was quantified using a Langmuir balance device designed and constructed in our laboratory (FR) according to Verger and de Haas. " ... 

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