Reliability – The Nash design has the unique advantage of simplicity. Nash compressors are single stage. A single stage unit is a simpler design with fewer parts, which means higher reliability and reduced maintenance. This design eliminates the need for two staging, where tip speeds often exceeds 34m/sec. As rates of erosion accelerate rapidly with increasing rotor tip speed, reduced life and increased downtime/ maintenance can result. The HP compressor has only one (1) stage, which operates at a tip speed of 30m/sec or lower, thereby reducing rates of erosion, reducing vibration and enhancing reliability.


Bearings – The design life of the bearings is more than 20 years for normal operating conditions and proper maintenance. Also the double lobe design

does not require thrust bearings:


Due to the balanced design of these pumps the developed axial load is minimal. The anti-friction ball bearings are capable of withstanding combined axial

and radial loads. These bearings are designed to yield a B-10 life of 20 years. This far exceeds EEMUA, Section 2.9.2. Requirements.

The fully enclosed side-shrouded rotor of the conical design is inherently stiffer and thereby less prone to blade breakage. A disassembled view shows

the simple, rugged construction of a typical HP compressor. Note the fully enclosed end shrouds on the rotor.

The centered rotor of the double lobe conical compressor has diametrically opposed porting with counteracting discharge pressure and forces eliminating

shaft deflections.





Gas compression Visualization action. 

Schematic section at inlet Trace what happens in a single rotor chamber and discharge sectors, as it goes around a complete revolution.

Efficiency – The volumetric efficiency of the compressor is approximately 90%.


Flexibility and Tolerance of Changing Process Conditions – The ability to tolerate changes in process flow (both liquid as well as gas) and maintain pressure and temperature control is enhanced by nash_elmo unique conical design.


Large, open inlet port passages in their cones enable the compressors to handle:



      1. Liquid carryover from your system

      2. Excess seal liquid rates optimising process vapour condensation and recovery.


Benefits are:

1.  Higher seal liquid rates, resulting in lower temperature operation.

2.  Ability to handle liquid carryover or excess seal liquid flow resulting in better pressure control during upset condition.

3.  Increased efficiency.

4.  Easier and more accurate assembly.


Sealing Liquid Functions – The operating liquid has three main functions, they are:

      1.  It removes the heat generated during compression.

      2.  It maintains the stability of the liquid ring.

      3.  It seals the axial clearance since the impeller rotates without any metal-to-metal contact.


Experience – Nash has an extensive worldwide installation list. Customer testimonials reflect a proven track record on process application.


Service/Parts Backup – Nash Technical and Distribution Centers throughout the world have trained Service staff and parts availability. Commissioning, start-up and service can be arranged from our local facility in Singapore.






Nash’s only business is Engineered Vacuum and Compressed Gas System. We have to be the best at designing, engineering, packaging and servicing our product. Our commitment to excel in this endeavor is a total corporate effort by Nash employees worldwide.