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Buoyancy Floats

Primarily used for feed density detection, the buoyancy float can also be applied to product density if a suitable mounting location near the evaporator can be found. Because flow will affect the measurement, the float must be located where the fluid is almost stagnant or where flow can be controlled (by recycle) and its effects zeroed out. A Teflon-coated float helps reduce drag effects. [Pg.306]

Several methods have been used to control the amount of heat removed in a given condenser. Some of these include controlling the cooling medium flow-rate or temperature, changing the amount of surface available for heat transfer, and introducing inert gases into the condensing vapor. [Pg.306]


Product concentration can be controlled by measuring a number of physical properties. On-stream composition analyzers are often used. Commonly used physical properties include density, boiling point rise, temperature/pressure combinations, temperature difference, conductivity, differential pressure, refractive index, buoyancy float, and viscosity. Each method has certain advantages as well as limitations. In all cases, however, a representative measurement location must be carefully selected to eliminate entrained air bubbles or excessive vibration, and the instrument must be mounted in an accessible location for cleaning and calibration. The location of the product quality transmitter with respect to the final effect should be considered also. Long piping runs between the product and the instrument increase deadtime, which in turn reduces the effectiveness of the control loop. [Pg.304]

Potential probes have been developed that are anchored near the pipeline with buoyancy floats and electrically connected to the pipeline. These probes are switched on by coded signals from the ship they read the potential and... [Pg.388]

Oil sampler according to Schomaker, glass bottle, lateral buoyancy floating bodies, sampling of surface layers of a few mm thickness 0.15 surface TO HB... [Pg.10]

A great variety of level measurement techniques are available. These involve point-contact, visual, buoyancy, float, and hydrostatic methods, and radio-frequency, ultrasonic, microwave, nuclear radiation, resistance tape, and thermal level systems [3]. [Pg.606]

Variable-Area Flow Meters. In variable-head flow meters, the pressure differential varies with flow rate across a constant restriction. In variable-area meters, the differential is maintained constant and the restriction area allowed to change in proportion to the flow rate. A variable-area meter is thus essentially a form of variable orifice. In its most common form, a variable-area meter consists of a tapered tube mounted vertically and containing a float that is free to move in the tube. When flow is introduced into the small diameter bottom end, the float rises to a point of dynamic equiHbrium at which the pressure differential across the float balances the weight of the float less its buoyancy. The shape and weight of the float, the relative diameters of tube and float, and the variation of the tube diameter with elevation all determine the performance characteristics of the meter for a specific set of fluid conditions. A ball float in a conical constant-taper glass tube is the most common design it is widely used in the measurement of low flow rates at essentially constant viscosity. The flow rate is normally deterrnined visually by float position relative to an etched scale on the side of the tube. Such a meter is simple and inexpensive but, with care in manufacture and caHbration, can provide rea dings accurate to within several percent of full-scale flow for either Hquid or gas. [Pg.61]

Buoyancy. The low density, closed-ceUed nature of many ceUular polymers coupled with their moisture resistance and low cost resulted in their immediate acceptance for buoyancy in boats and floating stmctures such as docks and buoys. Since each ceU in the foam is a separate flotation member, these materials caimot be destroyed by a single puncture. [Pg.416]

A buoyant spherical particle of diameter D floating in a Hquid which has no tendency to wet, ie, pull the shoreline up, or to reject, ie, push the shoreline down, the soHd submerges to a depth d at which the downward force of gravity on the sphere equals the upward buoyancy force of the displaced Hquid. This occurs when... [Pg.541]

External floating roo cheaper to constmct than double deck for 5—50-m diameter suitable for high vapor pressure stocks capable of in-service repair of appurtenances good buoyancy... [Pg.312]

Externa.1 Floa.ting Roofs. Pontoon roofs are common for floating roofs from diameters of approximately 30—100 ft (10—30 m). The roof is simply a steel deck having an annular compartment that provides buoyancy (Fig. 5a). Double-deck roofs (Fig. 5b and 5c) are built for very small floating roofs up to about 30 ft (10 m) in diameter. These are also used on diameters that exceed about 100 ft (30 m). These roofs are strong and durable because of the double deck and are suitable for large-diameter tanks. [Pg.314]

The force exerted on a submerged planar surface of area A is given by F = p A where p is the pressure at the geometrical centroid of the surface. The center of pressure, the point of application of the net force, is always lower than the centroid. For details see, for example. Shames, where may also be found discussion of forces on curved surfaces, buoyancy, and stability of floating bodies. [Pg.634]

Rotameter A rotameter consists of a vertical tube with a tapered bore in which a float changes position with the flow rate through the tube. For a given flow rate the float remains stationary since the vertical forces of differential pressure, gravity, viscosity, and buoyancy are balanced. The float position is the output of the meter and can be made essentially linear with flow rate by makiug the tube areavaiy hn-early with the vertical distance. [Pg.762]

Most large floating roofs are made from a single layer of steel, except around the edges, where there are hollow pontoons to give the roof its buoyancy. The single layer of steel is liable to crack, and any spillage should be covered w ith foam and then removed as soon as possible. Double-deck roofs are obviously safer but much more expensive [14]. [Pg.129]

Schwebe, /, siispension siispense sling suspender. -f gkeit, /, floating power, buoyancy siispension property, -flora,/, (Biol.) phytoplankton, -korper, m. siispended substance floating body, -methode, /. siispen-sion method,... [Pg.400]

It should be noted that if this cementing operation were to be carried out using an inner drillpipe string to place the cement in the annulus, the above force of buoyancy would be reduced by the buoyed weight of the drillpipe. However, unless very heavy drillpipe were used, the casing and drillpipe would still float on the cement slurry. [Pg.1215]

That is, in the floating body, there should be a balance of forces due to the nuclear paramagnetic force as well as the gravity, the diamagnetic force, and the buoyancy (Figure 20A). [Pg.384]

Reliability or vulnerability of stability, buoyancy, and propulsion systems (for floating installations or vessels). [Pg.92]

Floating vessels for offshore operations offer reduced installation costs but also present additional vulnerability factors. All floating structures must ensure buoyancy integrity is maintained otherwise the vessel may sink with catastrophic results. Similarly propulsion are provided at some installations to provided position stability. All major vessels are required by insurance requirements and most marine regulations to maintain buoyancy systems and loss of position stability will impact ongoing operations. Both of these systems can therefore be considered critical support systems and must be evaluated for risk and loss control measures either thorough duplication and protection measures or a combination of both. [Pg.100]

Floating exploration and production facilities are sometimes provided on jackup rigs, semi-submersible vessels or ex-crude oil shipping tankers converted to production treatment vessels. These facilities are essentially the same as fixed offshore platform or installations except they are moored in place or provided with a temporary support structure instead of provided with fixed supports to the seabed. The major process fire and explosion risks are identical to the risks produced on offshore platforms. They have one addition major facility risk, that is the maintenance of buoyancy of the installation. Should fire or explosion effects cause a loss of buoyancy (or even stability) the entire facility is at risk of submergence. Adequate compartimization and integrity assurances must be implemented in these instances. [Pg.230]

If a magnetic force from the main solenoid is used which is just sufficient to hold the float on the bottom of the solution container, the buoyancy forces give... [Pg.584]

The physical transport of oil droplets into the water column, called dispersion, is often a result of water surface turbulence but may also result from the application of chemical agents (dispersants). These droplets may remain in the water column or coalesce with other droplets and gain enough buoyancy to resurface. Dispersed oil tends to biodegrade and dissolve more rapidly than floating slicks because of high surface area relative to volume. Most of this process occurs from about half an hour to half a day after the spill. [Pg.111]

Archimedes used the experience to develop what has come to be known as Archimedes s principle.This principle states that when an object is placed in a fluid, it experiences an upward force that is equal to the weight of the fluid that is displaced. Also known as the principle of buoyancy, it determines whether something sinks or floats. [Pg.69]

Metal double-deck or pontoon type floats designed according to API 650 have sufficient buoyancy to prevent sinking when half of their support chambers or pontoons are punctured or the access hatches are opened. [Pg.287]

A metal floating cover supported by liquid-tight metal pontoons or floats that provide sufficient buoyancy to prevent the tank s liquid surface from being exposed when half of the flotation is lost. [Pg.292]

Mark 5 Flares, Types 1 and 2 consisted of a cylindrical buoyancy chamber which contd two candles. To these were attached a fuze, a static cord and a pull igniter. The static cord functioned either the arming device of the fuze or the pull igniter. When the device was released (from a container) over the water it went under the surface and then came up. It floated with the head of the flare just clear of the water. When the 1st candle was about % burned out, a piece of safety fuse running to the 2nd candle was ignited and, after a short delay, die 2nd candle started to bum. Each candle burned for about 2% min... [Pg.454]

Foamed Explosives for Floating Mine. An invention fcy Stark (Ref 1) provides a floating mine which consists of an expl having a closed-cell foam structure of greater and more shattering effect than die same wt of high density expl. Buoyancies of these expls are of 20 to 50 lbs per cu ft. The foamed expls consists of HE s (such as TNT, NC, PETN or RDX) bonded by a thennosetting resin Ref H,J. Stark, USP 2845025(1958) Ordo 43, 662(Jan-Feb 1959)... [Pg.534]


See other pages where Buoyancy Floats is mentioned: [Pg.1253]    [Pg.306]    [Pg.1253]    [Pg.306]    [Pg.412]    [Pg.50]    [Pg.313]    [Pg.403]    [Pg.403]    [Pg.914]    [Pg.1212]    [Pg.23]    [Pg.24]    [Pg.101]    [Pg.116]    [Pg.151]    [Pg.215]    [Pg.584]    [Pg.586]    [Pg.154]    [Pg.145]    [Pg.288]    [Pg.30]    [Pg.473]   


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Buoyancy

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