Nash AT Series Replacement Pumps

Capacity 680 to 4,750 m3/h (400 to 2,800 ACFM)


The popular NASH AT two stage vacuum pump series has been providing reliable high vacuum performance in the power industry for over 25 years. With capacity ranging from 680 to 4,750 m³/h (400 to 2,800 ACFM) the AT’s four vacuum pump models are an ideal choice when you need a rugged and long-lasting machine to handle your saturated process gases.

Key characteristics:

• Harsh conditions
• Reliable and efficient

Designed to Operate in Harsh Conditions

The line of AT vacuum pumps is our first generation of two stage pumps designed specifically for the condenser exhaust duty. Including an integral two stage rotor, the AT vacuum pump is designed to reach vacuum levels down to 0.8 inHgA (28 mbar abs). This is approximately 40% lower absolute pressure than a single stage pump.

AT liquid ring vacuum pumps were created for the chemical, petrochemical, and power industries. With their integral two stage rotors, AT pumps, are able to condense vapors that come off the process and to recover or dispose of them.

Conical Porting and Rotor Configuration

Patented in 1932, Nash’s variable conical porting design allows the force of compression to counter the weight of the rotor and shaft to help minimize load on bearings during operation. The variable porting optimizes pump performance across the entire operating range. With constant innovation, Nash’s patented design features:

  • Option for lobe purge to minimize damage from erosion in duties with solids present
  • Large differential pressure capability
  • Gas scavenging feature minimizes slip of gas from discharge to inlet improving capacity, especially at deep vacuum
  • High liquid carryover tolerance
  • Side discharge to minimize chance of flooded start
  • Self-priming design may allow elimination of booster pump in recirculated systems

Reliable and Efficient with Proven Performance

The AT offers superior performance and reliability through the proven reliable NASH conical liquid ring pump design.

The first AT3006 vacuum pump was built and tested at a Nash facility with results showing an increased dry air capacity up to 25% in the high vacuum range without an increase in power usage. The AT3006 offers higher operating efficiency than the AT3004, and with today’s energy costs, efficiency is an important factor for our customers.