Meter operator

Momentum Flow Meters. Momentum flow meters operate by superimposing on a normal fluid motion a perpendicular velocity vector of known magnitude thus changing the fluid momentum. The force required to balance this change in momentum can be shown to be proportional to the fluid density and velocity, the mass-flow rate. 

Power. There are two main ways to measure the power deUvered by the driver to the pump. The first method is to install a torque meter between the pump and the driver. A torque meter is a rotating bat having a strain gauge to measure shear deformation of a torqued shaft. Discussion of the principle of torque meter operation is available (16). The benefit of this method is direct and accurate measurements. The power deUveted to the pump from the driver is calculated from torque, T, and speed (tpm) in units of brake horsepower, ie, BHP (eq. 4a) when Tis in lbs-ft, and kW (eq. 4b) when T is N-m. 

Head flow meters operate on the principle of placing a restriction in the line to cause a differential pressure head. The differential pressure, which is caused by the head, is measured and converted to a flow measurement. Industrial applications of head flow meters incorporate a pneumatic or electrical transmitting system for remote readout of flow rate. Generally, the indicating instrument extracts the square root of the differential pressure and displays the flow rate on a linear indicator. 

Positive-displacement (PD) flowmeters are used when the total quantity of the flowing process stream is of interest or when a recipe is being formulated in a batch process. These meters operate by trapping a fixed volume of fluid and transferring that volume from the inlet to the outlet side of the meter. The number of such calibrated "packages" of fluid is counted as a measure of total volumetric flow. These measuring devices are used in both gas and liquid services. 

The swirl meter operates in most of the same applications as the vortex-shedding flowmeter but has the advantage that, because flow conditioning is done at the inlet and outlet of the meter body, virtually no upstream or downstream straight run is required for optimal installation. 

Equation (8) was derived by Stern and Geary [10] and is the theoretical principle upon which many commercial corrosion rate meters operate. 

Determine the expansion factor and the meter area factor. Since steam is a compressible fluid, the expansion factor Y must be determined. For superheated steam, the ratio of the specific heat at constant pressure cp to the specific heat at constant volume cv is k = cp/cv = 1.3. Also, the ratio of the differential maximum pressure reading hw, in in of water, to the maximum pressure in the pipe, in psia, equals 120/246.7 = 0.454. Using the expansion-factor curve in the ASME Fluid Meters, Y = 0.994 for ft = 0.5999, and the pressure ratio = 0.454. And, from the same reference, the meter area factor Fa = 1.0084 for a steel meter operating at 640°F. 

Intermittent flow meter operation Entrained material in CO etdting separator Installed particle filter before flow meter... 

At other temperatures the pH of water differs from 7.00 (see Table 15.1). A change of one pH unit implies that the concentrations of HaO and OH change by a factor of 10 (that is, one order of magnitude). The pH is most directly measured with a pH meter (Fig. 15.3). The mechanism by which pH meters operate is described in Chapter 17. Figure 15.4 shows the pH values for several common fluids. 

The metering operation is considered to be critical with regard to the economics of the plant. If the metering of the reactants is not controlled within precise limits, then excess of carbon monoxide must be used to prevent dichlorine contamination of the final product. This is wasteful not only of carbon monoxide, but also of phosgene product in the condenser... 

A few types of flowmeters measure the mass flow rate directly, but the majority measure the volumetric flow rate or the average fluid velocity, from which the volumetric flow rate can be calculated. To convert the volumetric rate to the mass flow rate requires that the fluid density under the operating conditions be known. Most meters operate on all the fluid in the pipe or channel and are known as full-bore meters. Others, called insertion meters, measure the flow rate, or more commonly the fluid velocity, at one point only. The total flow rate, however, can often be inferred with considerable accuracy from this single-point measurement. 

For a given meter operating on a certain fluid, the right-hand side of Eq. 

Cross-sectional flow meters operate on the basis of determining a pressure difference between two positions with different cross-sections. The cross-sectional flow meters used in the laboratory consist of capillaries (cross-sections of 0.5-10 mm ) and different types of open manometers filled with water, silicone oil or mercury. The flow rate of the measured medium through the capillary is essentially directly proportional to the pressure drop measured provided that the length of the capillary is greater than its diameter by a factor of at least 100. 

After activation, the run was operated under steady state conditions to ensure that the catalyst had the expected activity and the conversion was stable. When this was accomplished, the operation was changed to the cyclic mode. This was achieved as follows. For the gas feed mixture a flow of 88 SL/h was used and to maintain the same flow during the switching conditions, both the H2 and CO flows were set at 88 SL/h. The flow was then switched between 100% CO and 100% H2 by the control of the Brooks flow meter operation. Only the CO or H2 was open at any one time during the cyclic operation. For instance, when the H2 was open for 41.8% of the time and the CO was open for 58.2% of the time, the overall H2/CO ratio was 0.7. 

Immediately after production, a cylindrical glass container d = 25 mm h = S5 mm) containing the eleetrode was filled with 90 ml of the emulsion. The electrode was connected to a Hewlett-Packard 4263B LCR Meter operating at a frequency of 1 kHz, and the conductivity was measured every 60 s under constant-temperature conditions (25.0° 0.1 °C). The electrode was coated with gold to eliminate polarization effects and corrosion of the electrode material. 

Dl. A gas permeation system with a cellulose acetate membrane will be used to purify a carbon dioxide-methane stream. The permeabilities are given in Example 17-2. The effective membrane thickness tj = 1.0 pm (a micron = 1.0 x 10 meter). Operation is at 35°C. p = 12 atm and Pl = 0.2 atm (a vacuum). The feed is 15 mol% carbon dioxide. Assume ideal gases. 

Crompton has developed a combined lubricant and heat stabiliser, called Mark 2910, for extruded PVC pipe. The special feature of this liquid product is that profile extruders do not have to buy a separate lubricant such as paraffin wax and add it by a further metered operation. 

The magnetic flow meter operates with a conducting fluid and a non-conducting pipe liner. 

Meter Operator This term describes a person , which will usually mean a company, who owns, installs, maintains or removes metering... 

Part VII addresses the supplies to installations and covers matters sueh as precautions against supply failure the suitability and maintenance of distributor or meter operator equipment on consumers premises the cireum-stances under which supplies can be connected and discoimeeted and the information that must be provided to consumers. A new requirement in Regulation 24 would mean distributors having to offer earth facilities with new connections at low voltage. Moreover, under Regulation 25, the distributor should not provide a connection if there are reasonable grounds to believe that the consumer s installation, or other distributor s network, does not comply with BS 7671 or other relevant standards. 

Orifice meters are not used in gas-solids flows also because of the erosion that will occur in time, giving unreliable or no results at all. Such utilization of orifices, turbine meters, venturis, and rotameters can still be used for gas flow metering and indeed they are employed. In addition, the sonic orifice principle or the Laval meter has been used with considerable success by many people for gas flow. These meters operate on the principle of having a sonic velocity at an orifice and as such, the upstream is not subject to the downstream pressure perturbations in the system. 

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