Glass Pipe Research Articles

High processing rates for glass pipe using Vello's method

High processing rates for glass pipe using Vello's method

Pressure Loss in the Pipe Bends, in which Granular Solids are Transported

The authors have examined experimentally the pressure loss in the pipe bends, in which granular solids are transported. In order to investigate the pressure losses an assumption has been made that the total pressure loss consists of the losees in the flow of ordinary fluids through a pipe bend and those due to solids. It has been shown that the former is presented by the known formula and the authors have obtained the tact that the pressure losses due to solids increases in proportion to the weight ratio of solids to air in flow. Moreover the flow of solids in glass pipe bends has been observed. The observation has helped us in taking account of the effect of solids flow upon the pressure losses due to solids.

Flow characteristics in horizontal fluidized solids transport

AbstractThe flow characteristics of dense solid‐gas mixtures transported through horizontal pipes were studied with glass beads and coal powders of various sizes (0.0028 to 0.0297 in.) in 1/2‐, 3/4‐ and 1‐in. glass pipes and a 1/4‐in. steel pipe. Fluidized‐bed feeders were utilized, thus permitting solid‐gas ratios considerably higher (range 80 to 750) than those possible with conventional pneumatic transport. When such high solid‐gas ratios are used, the flow of mixtures in transport lines is characterized by a large amount of slippage between gas and solids. The flow pattern is dicussed on the basis of visual observation through glass pipes.A simple and interesting velocity relationship was noted, namely that the average gas velocity is about twice as large as the average solid‐particle velocity. The solid‐particle velocities and solid loadings in the pipe line were found to be primary factors affecting pressure drops, and the particle sizes and shapes, on the other hand, exerted a very slight effect on the pressure drops. This is apparently due to the fact that the solids move predominantly in the bottom of the pipes as agglomerated masses rather than as individually suspended particles. A pressure‐drop correlation for the dense solid‐gas mixtures is proposed, and applications and limitations of the correlation are shown.

Propagation of Pressure Waves of Finite Amplitude in Boiling Water

Pressure pulses were produced in water boiling in a vertical glass pipe by initiating a shock wave in the gas above the liquid. The steepness of the wave front of the shock decays rapidly so that within a few centimeters below the surface the pressure takes several milliseconds to rise to the value of the shock pressure in the gas. For pressures sufficient to condense all the steam bubbles in the water, a very high pressure is observed at the instant at which all the steam is condensed. This large pressure amplification is due to the sudden deceleration when the water hits the end of the pipe. The observations corroborate computations. (This research was supported by the U. S. Atomic Energy Commission.)

Transition from Slow Burning to Detonation in Gaseous Explosives

High-speed photographic observations have been made of flame structure, flame velocity, and shock velocity during the transition from slow burning to detonation in acetylene-oxygen mixtures contained in glass pipe at reduced pressures. During intermediate stages the dome-shaped flame travels down the tube at about 800 m/sec and is preceded by a shock wave traveling slightly faster. During the final stages of formation of the detonation wave, the flame changes shape, accelerates, and advances along the walls in an asymmetric manner. The detonation first appears at, or slightly behind, the leading edge of the flame. The final flame acceleration occurs when the Reynolds number of the mass flow between the flame and the preceding shock, based upon the distance traveled by a mass element in the time interval between passage of the shock and the flame through it, is about 107. Under these conditions the development of turbulent regions in the boundary-layer flow ahead of flame appears likely. Changes in flame configuration which result in the final acceleration and the formation of the detonation wave then arise from the faster flame propagation into these turbulent areas than into the free-stream region.

Annealing of glass pipes (for discussion)

Annealing of glass pipes (for discussion)

Pressure Drop due to Friction for Parallel Flow of Mixtures of Vapour and Water in a Downcomer

In this paper, the author experimentally investigated the pressure drop due to friction for the flow of water containing bubbles in a non-heated downcomer. First, the pressure drop due to friction and dryness fraction for the parallel downward flow of the mixtures of air and water were measured in a vertical 1500 mm long and 19 mm inside diameter glass pipe. Next, the ratios of the coefficient of friction in high pressure regions were extensively computed from the results of the above experiment. Finally, in case we used nonheated downcomer, it was proposed that we might adopt 0.03 as an approximate value of the coefficient of friction.

Welding of glass pipes and fittings to ducts

Welding of glass pipes and fittings to ducts

Mass transfer in a horizontal liquid‐liquid extraction tube

AbstractA study was made of the effect of physical properties and of geometrical and dynamical characteristics of several liquid‐liquid extraction systems on the mass transfer coefficients. The two‐component systems studied consisted of the following solvents with water: cyclohexanol, methyl ethyl ketone, furfural, normal butanol, and nitromethane. The transfer studies were made in a horizontal glass pipe with the phases flowing counter‐currently at velocities from 1,000 to 15,000 lb./(hr.)(sq. ft.). The transfer of solvents into the water phase and of the water into the solvent phase was measured. The film coefficients of mass transfer for a solvent through the water film and for water through the solvent film were correlated by new dimensionless equations which include interfacial tension and diffusivity.

Industrial glass piping

Industrial glass piping

Industrial glass piping

Industrial glass piping

Industrial Glass Piping - Evolution and Present Application

Industrial Glass Piping - Evolution and Present Application

Characteristics of the Air Lift Pump for Various Liquids

The characteristics of the air lift pump for water under various conditions have been previously reported. During the past three years many experiments have been conducted with this pump relative to the use of many kinds of steel and glass pipes for soap suds, light oil, spindle oil, ammonium sulphate solution, muddy water, sandy water and wood powder water. The effects of physical properties of liquids on the characteristics of this pump have shown that the pump is nonsensitive to these properties on the whole.The main experimental results are as follows:1) Effects of surface tension between 35 and 80dyne/cm are negligible. (Fig. 1)2) Effects of specific density between 1 and 1.2g/cc are also negligible, if lifted quantity of liquid is expressed by volume. (Fig. 1, 6 & 7)3) Static viscosity makes lifted quantity decrease at larger flow quantity, but rather improves the characteristics at smaller flow. In the usual region between the optimum point (the max. efficiency)and the maximum liquid point, the next farmula is obtained. (Fig. 2-5)where4) The characteristics of three phase flow, which contains solid particles, are inferior. (Fig. 6, 7)5) Mean lifted velocity υm=(Q+V0)/A is a little lower than 1m/s at the optimum point, and is about 2m/s at the maximum liquid point in all cases.6) Instantaneous slip velocities between liquid and air are obtained by the salt water (electrical) method, and the slip is below 0.5m/s at the optimum point and about 1m/s at the maximum point. (Table 3)

Absorption of Carbon Dioxide by the Aqueous Solution of KOH in Pipe Reactor

Absorption of CO2 was carried out with the mixed phase flow of CO2-air mixture gas and KOH solution in vertical glass pipes of 12.8mm and 17.8mm i.d.The K2CO3 concentrations in the flowing solution were measured at various points along the pipe. This reator was, for convenience' sake, considered separately in two sections as divided according to the concentration gradients: one was the accelerating section where the concentration gradient was curved by the mixing effect, and the other was the steady flow section where the gradient was nearly linear.Mass transfer coefficients were calculated by the next equation:The effects of various factors on KGa were investigated in each flow section as follows: -1) for the accelerating section (0.17m)2) for the steady flow section3) for the whole section (1.26m)4) KGa was inversely proportional to the pipe diameter.5) KGa was increased with the KOH concentration within the Experimental range. (0.8-2.03 N KOH)

Pipe-end Flow Meter

Flow-rate u0[cm/sec] of the liquid from the end of a horizontal pipe (Fig. 1) can be calculated by measuring the distance x[cm] at the given level S[cm].(4)The experimental results obtained from water stream in the glass, brass and copper pipes showed that the coefficient C is constant in any case, and nearly equals 1.00 (C=1.00±0.02≅1), when u0≥120cm/sec.

THE CLEANING OF GLASS PIPING IN DAIRY PLANTS

The purpose of this study was to determine the relative efficiency of various chemical compounds used to clean permanently installed glass milk lines. Nine different commercial alkaline cleaners and four acid cleaners were selected.To evaluate the effectiveness of each selected cleaner, a continuous thirty-day test was made at two dairy plants.For purposes of comparison between physical (l80°F hot water) and chemical sanitization, a study of some of the more commonly used chemical germicidal agents was included.The nine commercial alkaline cleaners adequately cleaned Pyrex brand glass pipe but all quaternary-ammonium compounds used in this study were unsatisfactory either as cleaners or sanitizers.

On the Basic Study of Pneumatic Stowing (1st Report)

In this 1st report, the authors discussed the motion of accelerating period of one Qartz particle which moves by drag force of air stream in the horizontal glass pipe mathematically and experimentally for the first stage of the basic study of pneumatic stowing. In this experiment the velocities at the inlet and at the outlet of the pipe were assumed to be equal. In this agreement, the drag coefficients of the particles in the air stream were obtained from the sinking velocities of the particles in still water. By using the values of the drag coefficients, the motion phenomena in the air current in the glass tube were adequately explained, when the mechanical friction coefficient μ or the coefficient of resilience φ between the particles and the wall of the glass tube was properly selected by auxiliary experiments.

The measurement of velocities for solid-fluid flow in a pipe

When a stream of particles is conveyed by air or water in a glass pipe two photographs of a portion of the stream are superimposed on the same photographic negative. The pictures are taken by the light from a pair of discharge lamps, the time interval between the flashes being variable and measured by a rotating disk. A more satisfactory light source is a high speed stroboscope, the interval between flashes being predetermined by a setting of a multivibrator. The velocity of a particle is obtained from its displacement measured on the photograph. The method is illustrated by its application to the movement of gravel by air and coal by water.

THE USE OF GLASS SANITARY PIPES IN THE MODERN DAIRY

A permanent installation of glass pipes has been used in the University of Georgia Creamery for receiving raw milk for a period of two years. The pipes are installed in such a manner that they are washed and sterilized by continuous recirculation of the washing and sterilizing solutions. Bacteriological data were given which showed that the pipes can be adequately cleaned and sterilized by the recirculation method. After two years of daily use under normal operating conditions, the pipes contained practically no milkstone, were clean and shiny in appearance, and no breakage was experienced. A recommendation was made that milk sanitarians and health officials approve the glass pipe installations for receiving raw milk. The research is being continued.

Vertical Pressure of Sand in a Glass Pipe

Vertical Pressure of Sand in a Glass Pipe