Generate Oxygen Gas on-site and on demand from thin air. 

Southern Gas Services have been proudly working along side Oxygen Generating Systems Intl (OGSI) for many years.  Our partnership has enabled us to supply a complete line of OEM Pressure Swing Adsorption (PSA) generators with outputs form 7.5 L/min to 5 TPD.  The standard oxygen purity from these generators is 93% (+/- 3%).

As with or nitrogen generators, direct connection to the manufacturer translates into a system that is designed specifically for your production application, that is reliable, cost effective, safe and convenient.

OGSI currently have oxygen plants in over 70 countries worldwide, serving many diverse markets.  OGSI like us, are committed to providing innovative, highly engineered, quality equipment and support.

We personally rely on the simplicity and reliability of PSA gas generation and run several generators at our Head Office factory in Christchurch.  Have a look through the models listed below and if you have any further questions please contact us directly for a quotation for a generator based upon your current requirements.


OG-15 & OG-20

The OG-15 and OG-20 units are completely self-contained.  They come complete with an internal air compressor, filtration system, zeolite sieve, surge tank, and flow control system. They are designed for 24 hour un-interupted operation.

Weighing 36 kg the OG-15 and 20 are the small scale industrial strength oxygen concentrators.

The onboard compressor maintains an internal pressure of less than 32 psig and can deliver a flow of oxygen at between 7 – 9 l/min at a pressure of  9- 20 psig.  These units are registered with NZ MedSafe® on the WAND Database as an approved portable medical device (REF#140714-WAND-6HZOQR).

For ease of use, all of the controls are on the front panel.  The Power Switch, Hour-meter, Gauges, Regulator and Flow-meter are easy to view and/or adjust.


The OGS-20 oxygen generator uses Pressure Swing Adsorption Technology (PSA) to deliver a constant flow of up to 9 l/min of USP 93% grade oxygen, at a pressures up to 90 psi, which is ideal for Veterinary Clinics needing to run ventilators.

The system has been specifically designed to operate 24/7 and is built to last.

The unit automatically starts when the flow of oxygen begins from the storage vessel and automatically stops when the pressure in the vessel returns to full status.

* Is fully automatic
* Easy to operate and maintain
* Produces continuous medical grade oxygen
* Hundreds of systems installed worldwide since 1995
* WAND database registered for operation in NZ

OG-250/5000 SERIES

OG-250 generators and above are designed for applications requiring outputs from 25 to 5000 SCFH (12 to 2360 LPM) at a purity of 93% (+/- 3%).  Bespoke system designs means you will never pay for capacity you don’t use or need.

OGSI’s plants are PLC controlled and are some of the most energy efficient plants currently on the market.  The zeolite sieve, is factory sealed in solid steel vessels, and rarely needs replacement.  With very few moving parts, OGSI generators are built to provide thousands of hours of continuous, reliable service.  Routine maintenance is as simple as changing an air filter.

Our range of oxygen generators are economically priced so that you can realize a return on investment within a short period of time. Contact us today for a competitive quotation.


MOGS-50/100.  This system is completly modular, containing all of the required components and are designed to produce oxygen in accordance with the US Pharmacopeia specifications and fill high pressure cylinders at the customers location. These systems are targeted for emergency disaster relief where regular oxygen delivery supply chains often become broken.

CFP-15M. This unit is the military high pressure equavilent of the portable oxygen concentrator.  This unit is specifically designed to be highly transportable with the primary objective being use within the battlefield hospitals. Capable of filling high pressure cylinders and being compact (mounted on its own cart) makes it an invaluable addition to any military medical facility.

For more information on these and other available oxygen generators please feel free to contact us


All oxygen generation systems, large or small, contain the same components, just in varying sizes and configurations.

In order to separate the oxygen gas from the air mixture at room temperature, it must be compressed to a minimum pressure of 100 psig (approx. 7 barg).  Once the air is compressed it is then filtered, cooled and the moisture is removed via a refrigerated dryer resulting in very clean and dry air (Dewpoint -70 C).  The input air quality is a significant factor in maintaining the longevity and purity of the overall system.  The process air is then feed onto the PSA beds where the air is separated into its components.  In the case of oxygen gas, all other components are considered as contaminants and are retained on the molecular sieve within the towers and expelled as waste gas during the purge cycle of the process.

Because the system constantly cycles from a state of production, to purge/recycling, the gas produced is not supplied as a continuous stream therefore, a buffer vessel is required to smooth out the gas supply and provide a small storage reservoir.

Maintenance is as simple as changing filters on the generator and following the manufacturers advice on any standalone compressors.

Life expectancy of our equipment is estimated at greater than 20 years. We presonally have PSA generators that have been performing day after day for the last 16 years.

The example below has a high pressure cylinder filling option (additional) for on or off site use.