The Digester is designed for a working pressure of 3.5 kg/cm2 (or 50 psi) in the steam jacket and hydrostaticall tested to 6.5 kg/cm2 (or 90 psi). The shell is manufactured of 12 mm thick mild steel plate. Steam Jacketed Wall Plate is manufactured of 10 mm thick mild steel plate to BS 15 specification, which is arranged to give a steam space of approx. 25 mm (Not available for Non-steam jacketed Digester). The Wall Plate and Inside Wear Plate (liner) is manufactured of 10 mm mild steel plate. The Digester discharge opening is to be provided at the bottom of the Digester through the shell wall and the mild steel door of operated by a mechanism rack and pinion. The Chute is from 6 mm mild steel plate. The Bottom covered plate is approx. 20 mm thick mild steel plate. The internal perforated wear plate is 18 mm thick and suitable arranged in two sections for ease removed and fixing. Stainless Steel Chute, extra thickness of the Internal Wear plate (Liner) and Bottom Perforated Wear plate can be supplied by extra costs subject to confirmation.
The Shaft consists of two lengths, one short connecting shaft and one long Stirring shaft. The short shaft of 88 mm diameter is coupled between the output shaft of the Reduction gearbox and stirring shaft. The long Stirring shaft is manufactured from square shaft or round bar suitable coupled by cast steel solid flange coupling. Bearing centralizes the bottom end of the long shaft and bearing housing is machined from cast steel.
The Digester Arms are made from cast manganese Steel. V clamping block of Cast steel locked with high tensile steel bolts and nuts fixes the Arms to the square section of the shaft.
The Digester, on satisfactory completion of hydrostatic test is to be painted with heat resisting bit mastic paint and insulated with rock wool blanket or other equivalent insulating material. The blanket is then covered with G20 stainless Steel or aluminum lining. The jointing of the stainless steel or aluminum sheet is covered with suitable size strap. All necessary supports, rings etc. are provided. The standard Fitting are equipped in the supply such as steam valves, non-return valves, steam trap and discharge cock. Vacuum Breaker, Automatic Temperature Regulator and level Indicator are not necessary but also can be supplied by extra costs subject to confirmation.
The Stirring shaft should be driven from the top of the digester by mean of a squirrel cage motor direct coupled or V belt drive with a reduction gearbox. Hydro Fluid coupling is also available for both drives.
|Digester Model||Volume Approx. Litres||Diameter (mm)||Height (mm)||HP Required||No. of Digester Arms||No. of Expeller Amrs||Main Stirring Shaft (Sq. mm)|
|LD 4500||4500||1400||2900||40 - 50||10||2||127|
|LD 5000||5000||1400||3200||50 - 60||10||2||127|