Swing lines

Swing lines made up of pipe with flexible joints and provided with a counterbalance is the preferred method of transferring hazardous chemicals into or from a tank vehicle. Hoses, no matter how thoroughly reinforced, have lower pressure capability and are easily damaged in use. Rupture of transfer hose is a not uncommon cause of employee injury or spill of product. Metallic tubing with braided exterior has admirable qualities, but a sharp bend, particularly near the end, causes weakening and failure, which is often neglected before the failure. 

Products and economics The process yields a variety of superior products with attractive investment and conversion costs. These products are sold and well accepted worldwide. INEOS offers commercially proven swing-line technology, capable of producing both GPPS and HIPS grades, with capacities ranging from 60,000 tpy up to 200,000 tpy that provide a turndown capability of 60%. 

U) If a tank is equipped with a swing line, the swing pipe shall be raised to and secured at its highest position. 

At a uniform rate, lower the bottle assembly as near as possible to the level of the bottom of the outlet connection or swing line inlet and, without hesitation, raise it such that the bottle is approximately three-fourths full when withdrawn from the liquid. 

Most of the situations encountered in capillarity involve figures of revolution, and for these it is possible to write down explicit expressions for and R2 by choosing plane 1 so that it passes through the axis of revolution. As shown in Fig. II-7n, R then swings in the plane of the paper, i.e., it is the curvature of the profile at the point in question. R is therefore given simply by the expression from analytical geometry for the curvature of a line... 

Swing Check Valves These valves (Fig. 10-156) are used to prevent reversal of flow Normal design is for use only in horizontal lines, where the force of gravity on the disk is at a maximum at the start of closing and at a minimum at the end of closing. Unhke most other valves, check valves are more likely to leak at low pressure than at high pressure, since fluid pressure alone forces the disk to conform to the seat. For this reason elastomers are often mounted on the disk. Swing checkvalves are available with low-cost insert bodies. 

Tilting-Disk Check Valves These valves (Fig. 10-160) may be installed in a horizontal line or in hnes in which the flow is vertically upward. The pivot point is located so that the distribution of pressure in the fluid handled speeds the closing but arrests slamming. Compared with swing checkvalves of the same size, pressure drop is less at low velocities but greater at high velocities. 

While the former would stress the generator windings, the latter may cause a voltage swing during a load rejection or load fluctuation and result in a line outage. These features, if not controlled, may render the system unstable. Overvoltages must therefore be controlled within an acceptable limit. Table 24..3 prescribes one such limit. 

For the system to remain stable under all conditions of loading, switching, or any other line disturbances it is essential that an uncompensated line is loaded at much below this level. Otherwise disturbances of a minor nature may result in undampened oscillations, and may even swing the receiving-end voltage beyond acceptable limits. It may even cause an outage of the system. It is therefore not practicable to operate an uncompensated line to its optimum level. For this we will analyse this equation for sin 0 and sin S as follows. 

Curve 2 with partial compensation, the voltage profile improves and the line is able to transfer more load than above, but less than its natural loading. Voltage still sags but the swing is more tolerable. 

A line can be theoretically loaded up to these levels. But at these levels, during a load variation, the far-end voltage may swing far beyond the desirable limits of 5% and the system may not remain stable. With the use of reactive control it is possible to transfer power at the optimum level (Pnias) hd yet maintain the far-end (or midpoint in symmetrical lines) voltage near to and also to have a near-flat voltage profile. 

Reactive control can alter the line length ( f LC) to the level at which the system will have the least possible swings. It is evident from these curves that an uncompensated line of a much shorter length may not be able, to transfer even its natural load (Pq) successfully. This is due to the steeply drooping characteristics of the voltage profile at about this load point, which may subject the... 

Figure 1.147. Jackson s curve and arc stress reorientations. Apparent swing motion of Pacific Plate (Jackson et al., 1975) and regional stress orientation at the Northeast Honshu convergent margin are illustrated in order to show their synchronous relationship. Dashed line represents the average trend of the Hawaiian volcanic chain. Pacific plate moves along the direction with fluctuation in reference to Hawaii Hot Spot. Vertically shaded parts of the graph indicate the climax phases of clockwise episodes . Lower part of the figure shows the phases and reversals in orientation of tectonic stress fields on the inner zone of Northeast Honshu Arc (Takeuchi, 1987).

Krauch Yes, sir. [The microphone swings before his sallow face, While his counsel has orated, he has shifted uncomfortably., looking down the first row at his colleagues, who have not returned his glance. As time goes on, we shall realize they mean to show they do not know the Professor very well but at this moment the picture is like that of an officer dressing-up a line of troops.]... 

Another feature of boiler operations is the widely varying demands caused by changes in process operations, plant unit start-ups and shutdowns, and daily and seasonal cycles. Because utility equipment is often operated in parallel, demand swings commonly affect when another boiler, turbine, or other piece of equipment should be brought on line and which one it should be. 

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