The ACD sealess centrifugal pump was designed for long life with zero leakage. The pump line eliminates the need for a conventional shaft seal by connecting the pumping portion of the unit to the section that holds the motor. The entire assembly is designed as a pressure vessel.
       The reliability of the sealess pump begins with motor design and production. Advanced heat transfer techniques allow for the design of a motor which doesn't require the flow of the pumped fluid through the air gap for proper cooling. This prolongs insulation life and reduced windage loss caused by liquid in the air gap.

Inducers are available to provide the lowest possible NPSH by employing computer analysis utilizing hydraulic paramenters. The inducer acts to generate an adequate amount of pressure to allow the main stage impeller to operate without cavitation. Cavitation not only limits flow (or prevents it altogether), but is extremely destructive to the rotating elements. The bearings may be damaged, the impeller and case wear rings will deteriorate rapidly, and the overall pump performance and efficiency is compromised.

The sealess pumps' lubricated bearings are designed and manufactured to ACD's exacting specifications. Bearing lubrication and cooling is achieved by diverting a portion of the pumped product flow through the bearings. Through proper selection of internal bearing geometry, coupled with the required amount of cooling flow, bearing life expectancy is greater than that of a conventional grease lubricated bearing.

The sealess pumps are available in a wide range of performance requirements. Contact ACD for more information.

Features & Benefits

• Pump and motor are fully flooded with liquid, minimizing start-up and downtime and guranteeing quick, responsive pumping
• Sealess design minimizes maintenance requirements
• No suction vessel means lower cost
• Multi frequency motor provides an efficient and broad range of operation and power
• Sealess zero leakage design is environmentally safe releasing no volatile organic chemicals and contaminates (VOC's) into the atmosphere
• Electrical motor and bearing life is extended being cooled by the cryogen it is pumping, heat input is minimal and carried off by discharging liquid
• Low NPSH inducer coupled with a variable speed soft start motor eliminates cavitation at pump start-up
• Suitable for Class I, Div I (IEC Zone 0 and 1) Liquids Pumped N2, Ar, CO2, Methane ( LNG, Ethylene, C2H4)