Waste heat recovery is an economic method to increase the overall efficiency of the plant and, thus, to lower fuel demand. Exhaust gas of various processes carry a huge amount of energy also referred to as waste heat. Often industrial processes produce enough waste heat to generate electricity.


ORC systems convert waste heat into electricity, ORC is a proven technology, using turbines as a generator drive usually with total output often in the MW range. An ORC system with electric output in the range from 3kW to 30 kW is so far quite rare. In this power range the use of turbines is questionable and other generator drives are difficult to find.


The Armak Gas motor range can be used on various

non-corrosive gaseous working media. The Armak Gas Motor is designed to work on a maximum pressure of 15 bar and a maximum temperature of 135°C.


Consider as an example a combustion engine in Combined Power and Heat Plant, typical drive power from 100 to 500 kW. These engines have an efficiency below 40%, the rest is wasted in the exhaust gases and the cooling water. The conversion of even a small part of such energy into electricity is a major advantage.


Armak Gas Motors can be driven by any non-corrosive gaseous media up to 15 bar and 135°C.


Technical details and product advantages:


• Frictionless torque produced, resulting in long and maintenance

  free lifetime


• Completely enclosed motor casing


• Compact design and freedom of installation


• Can be supplied with magnetic coupling


• Metric flange + shaft



The torque is developed by one power piston which is transferred to the output shaft by a second contact free rotating piston via a precision synchronized gear train. Both pistons rotate without physical contact resulting in near frictionless operation. The result being long maintenance free operation without downtime.

Typical applications for Armak Gas Pressure Motors are Solar Technology (collectors / mirrors) or Combined Heating and Power Systems.  Here the exhaust of the combustion engines is fed into a heat exchanger. A suitable fluid is inserted and vaporised, pressurised gas up to 15 bar can be produced and delivered to an Armak motor which in turn through a generator creates

electric power.


Armak Ltd are developing a turn-key system containing the pump, heat exchanger, motor and generator. The system should be ready for marketing in the near future. Alternatively, we can supply just the key components, the fluid metering pump and Gas Pressure Motor.


Armak Gas Pressure Motors can be run on various non-corrosive fluids/gases, the lubrication and seals need to be matched to the operating medium. Please consult Armak Ltd with your exact operating parameters.





Armak Ltd. Alexandra house, English street, Hull, East Yorkshire, UK, HU3 2DJ

Phone: +44 (0) 1482 595 000 Email: