Excess flow

Installation of internal excess flow or fail-safe remotely operated valves for tanks at locations where piping connects... 

Provide excess flow check valve upstream and check valve downstream of hose... 

It is therefore recommended that a small resistance of a low- /- R loss be introduced into the filter circuits as shown in Figure 23.15(a) to limit such an excessive flow of currents through them. Knowledge of the system parameters (resistance and reactance) is also essential to design an appropriate filter circuit to avoid a possible resonance in the first instance. If this occurs the resistance thus introduced will limit the excessive flow of current. 

Excessive Power Consumption Head too small, excess flow. High specific gravity or high viscosity. Bent shaft. Bound shaft. Incorrect rotation. 

The collection medium for gases can be liquid or solid sorbents, an evacuated flask, or a cryogenic trap. Liquid collection systems take the form of bubblers which are designed to maximize the gas-liquid interface. Each design is an attempt to optimize gas flow rate and collection efficiency. Higher flow rates permit shorter sampling times. However, excessive flow rates cause the collection efficiency to drop below 100%. 

Fit an excess flow valve to the outlet of a regulator, selected to allow the maximum required gas flow. 

Normally an overcapacity line to an elevated flare is provided to handle the excess flow when the flaring rate exceeds the capacity of the multijet flare. The overcapacity flare is usually not equipped with steam injection, and smoke formation is accepted during infrequent operations. The overcapacity line and flare is designed to handle the entire maximum flow so that it can spare the multijet flare when the latter is shut down for maintenance. 

Use physical limits of pipe size, restrictive orifices, and pump sizing to limit excessive flow rates. 

Freeman, R. A. and Shaw, D. A., Sizing Excess Flow Valves, Ibid., p. 176. 

If we say that, with a given applied field, in unit time this excess consists of n electrons, the current density will be Ne, since we are dealing with unit area. In Fig. 16 let us suppose that the excess flow of electrons is in the downward direction we can then, to show the character of the flow, make the following construction. Parallel to the plane AB, consider a plane CD, also of unit area and let the distance between CD and AB be chosen such that the total number of conduction electrons in the volume between CD and AB at any moment is n. 

Let us now consider the situation when this balance has been upset by the presence of a weak electric field perpendicular to AB. The motion of the ions will no longer be completely random, but a tendency to drift will be superimposed on the random motion. If in unit time there has been an appreciable excess flow of negative ions across AB in one direction, we can be certain that there has been an appreciable excess flow of positive ions across AB in the opposite direction. These two separate contributions will together constitute the electric current. 

Activated carbon filters remove a wide range of organic matter by adsorption onto the carbon bed. The bed may be derived from a number of different carbon sources, and the correct selection of bed type, capacity, and porosity is a specialized function. Activated carbon may be usefully employed in organic traps, complementing the resin bed, but its capacity and organic removal rate characteristics are flow-dependent. Excessive flows may compromise the rate of adsorption of organic matter. 

A joining part of the spiral coil or the quartz part that is in contact with stainless steel in the flow cell might not withstand high levels of pressure (generally smaller than 10 kg/cm2) hence careful operation to prevent excess flow is... 

Piping Rating, Codes, Cross-Connections, Purging, Excess Flow Valves... 

Checking for surge conditions and suitability of gas turbine units because of excess flow in case of syngas on account of it being a lean gas... 

Can passive leak-limiting technology (e.g., blowout resistant gaskets and excess flow valves) be utilized to limit potential for loss of containment ... 

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