While several methods for melting frozen or crystallized MDI have been developed, the method of choice should be one in which dimer formation is minimized. This can best be accomplished by rapid, even heating of the drums while rolling during heating.
The preferred method for heating drums is “drum rolling” (usually at 1-5 rpm on a mechanical drum roller) in 100Deg C Hot Air or Direct Steam Purging.
The principal advantage of this method is that it permits efficient heat transfer – that is, the solid MDI crystals cool the liquefied material so that the contents are not heated much beyond 70°C (158°F), the point at which dimer formation can increase significantly.
Experience has shown that a frozen drum of polymeric, pure or modified MDI, with a temperature between -4° to 32°F (-20° to 0°C), will usually melt completely (i.e., reach 70°C [158°F] in approximately four to (158°F), five hrs.
Low RPM high torque Gearbox specially designed to rotate 5-6 drums at a time. Two gear boxes provided with motors provided outside hot box with chain sprocket assembly. Mesh Guard provided on sprocket chain assembly.
Exhaust blower provided with Door Inter locking. It helps to prevent hot air from operator after opening doors.
Robust steel frame construction with mild steel cladding and insulated with mineral wool from all sides. Internal:-M.S./S.S. External:- M.S./S.S.
Electrical/Steam/Hot oil/Hot Water. Heater Bank provided with maximum efficiency and robust design. Electrical Heaters Equally distributed in 3 phases with FLP Cold Termination.
2 Rollers with EPDM rubber lining provided to roll sinvle drum horizontally. Chain Sprocket arrangement provided to rotate rums at steady speed i.e. 1-5 RPM.
60 kW Electrical heaters for 10 drum heating system, Steam Heat exchanger/Hot Oil heaters also available as option.
Intern alarmored cabling provided from control panel to all Electrical components with cable trays and cover.
To Fast and uniform heating rollers rotate in both clockwise and anti clockwise direction in cyclic action.
Centrifigal Blower provided with motor 1440 rpm, 3000cfm For Re-Circulation of Hot Air.