Finned Tubes

We supply around 70,000 finned tubes from our Wakefield factory every year. They help to reduce the costs of waste heat recovery and associated maintenance. Our ongoing investment in manufacturing equipment and staff training means that fin fabrication and welding of fins to tubes is extremely accurate and resilient.

Steel H finned tubes

We produce proprietary Single or Double Steel H finned tubes in carbon, low alloys or stainless steel, For double finned tubes, fins are welded onto two tubes simultaneously reducing the manufacturing time and the number of supports required and the resulting costs.

Green’s has tooling available for over 40 fin shapes and sizes and can produce other customised fin shapes if required.


Green’s Steel H fins bring significant benefits to waste heat recovery installations.

They include:

  • Compact design – fewer tubes are required reducing capital investment
  • Operating costs are less because the need for power for fans and pumps is reduced by the reduction in pressure losses
  • Steam or water is heated more quickly as there is around 9 times more heating surface
  • Fouling is kept to a minimum by the straight paths through the whole tube bank which allows dust particles to pass through easily
  • Because they are more efficient and require less maintenance, boiler downtime and its effect on business performance is kept to a minimum

Benefits of Green’s steel H fin economisers vs plain tube economisers when used in a 274MW boiler:

 Plain tube economiser   Steel H fin tube economiser
124 Number of rows 36
16m Height 5m
446 tonnes Weight 240 tonnes
£928,000 Cost £385,000

Spiral finned tubes

Where heat recovery equipment is used in clean environments such as with natural gas or light oil fired units or for preheating of combustion air, we often recommend spiral finned tubes. This gives an even greater surface area which leads to increased waste heat recovery for use in other applications. Spiral finned tubes can be fabricated with solid or serrated profiles depending on the environment in which they are going to be used.

Cast iron tubes

For low temperature applications prone to acid dew point corrosion we sometimes design cast iron economisers, which we have produced for many years for low temperature and dirty fuel applications. While they are very different from our compact and efficient H fin models, they are hard wearing and heavy and still suite certain retrofit applications. We offer a range of types including round or square fins such as Foster, Type 55 and Type 25. They are most commonly used primarily in  sulphuric acid, chemical, fertiliser and waste to energy plants.