. The manufacture of pulp and paper : a textbook of modern pulp and paper mill practice. the corresponding speed of the grinder lineis 246 If the cylinder pressure remained constant at 60lb. per sq. in., and the power input also was constant, the finalspeed of the turbine would be about 278 The effect of theuse of this direct-connected pump, therefore, is to reduce thespeed variation of the grinder stones. This is because an increasein grinder speed immediately causes an increased pump speed, 1 This curve was plotted from data given in the catalog of a manufacturerof pumps used f
. The manufacture of pulp and paper : a textbook of modern pulp and paper mill practice. the corresponding speed of the grinder lineis 246 If the cylinder pressure remained constant at 60lb. per sq. in., and the power input also was constant, the finalspeed of the turbine would be about 278 The effect of theuse of this direct-connected pump, therefore, is to reduce thespeed variation of the grinder stones. This is because an increasein grinder speed immediately causes an increased pump speed, 1 This curve was plotted from data given in the catalog of a manufacturerof pumps used for this type of service. 94 MANUFACTURE OF MECHANICAL PULP 53 which is reflected in higher pressure of wood on the stone, produc-ing a greater braking effect which then slows down the reader is referred to characteristic curves for medium speed,medium head, centrifugal pumps for further study of the action ofthis form of layout. These may be found in some of the standardmechanical engineering handbooks. Curve 5t?ow//7# /fe/ar/o/? q/ Speed aydPressureof Cep/r/fuga/ Furwps. 20 30 40 50 60 70 30 90 /OO /IO /20 /JO J40 /JG /60 /fO /SO /MPressure //? Pounds per ^fuare I/?cf? Fig. 49. 114. Constant-Pressure Centrifugal Pump, with ReducingValve and Air Cushion.—Fig. 50 gives a diagrammatic layout ofthe system. It is the same one as included in Fig. 40. Thecentrifugal pump K in Fig. 50 operates at constant speed andmaintains a delivery pressure somewhat in excess of what isrequired for the grinders. The reducing valve G is adjustableand controls the pressure in the grinder hydraulic cylinders. Thewater delivered to the grinders passes through pipe line J, intowhich is connected a tank /. This tank is kept about two-thirdsfull of air under the same pressure as the water. The objectof this tank is to equalize the pressure of the water in the systemwhen a large number of pockets arc thrown off at the same being practically incompressible, the result of a largevolu
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpaperma, bookyear1921
