The SIHIdryAS250/AS400 is based on a dry screw-spindle principle. The counter rotating screw shaped rotors, rotate without contact, eliminating the need for lubrication. Top down (self-draining), pumping is achieved by the top inlet and bottom discharge.
Synchronization of the two rotors is done electronically, removing the need for mechanical gearing. The electrical control devices, including variable frequency drives (VFD) and microprocessor are mounted in the SIHIdry control box.
For emergency conditions a set of non-lubricated, normally non-contacting (hence non-wearing), gears are provided to prevent rotor to rotor contact during emergency power or control outages.
Features: SIHIdry AS250/AS400 • Contain no oil lubrication or sealing fluids
• Capable of low temperature dry compression to T4
• Rugged cartridge bearings with no upper shaft bearing
• Ductile iron shock pressure tested casing (225 psig)
• Electronic drive synchronization and control
• Fail safe gas purged motor casing for ultimate hazardous area duty
Technical Data:
Pump AS250 AS400
Nominal suction capacity 150 ACFM 250 ACFM
Ultimate suction pressure < 1 mm Hg Abs < 1 mm Hg Abs
Speed range max.4500 rpm max.5500 rpm
Surface temperature in the
working chamber max. 300°F (150°C) max. 395°F (200°C)
Power consumption max. 10 HP (8kW) max. 13 HP (10 kW)
Purge gas consumption approx. 1.0 SCFM approx. 1.0 SCFM
Discharge pressure max. 1.5 PSIG 1.5 PSIG
Sound level, bare pump < 64 db(A) < 64 db(A)
Weight of the bare pump approx. 1100 lbs. approx. 1100 lbs.
Note: Refer to the Factory for combination of vacuum boosters & SIHIdry systems for capacities up to 4,000 ACFM
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