A Leeds based manufacturer of solar assisted heat pump systems improved quality and examined the potential to cut costs by using innovative welding technology, following feasibility trials by TWI under FriSC,a regionally fundedbusiness support programme.
Endoenergy Systems Ltd is co-ordinating the Endohousing project. It is an initiative funded by the European Commission under the Energie Programme to investigate using renewable energy sources to supply heating and hot water inhouses.
Endohouses demonstrate the potential for major savings in space heating and cooling costs using endothermic technology. A key feature is the array of liquid filled aluminium panels as solar energy collectors and heat exchangers.These panels can form the roof, wall cladding or could be a standalone structure. Further information can be found on the Endohousing website: www.endohouses.com
The panels are constructed from aluminium extrusions with end-caps welded on to seal the units, and manifold connections to allow circulation of the liquid around the system. The standard method of fabrication is TIG welding.However, the end product was not totally satisfactory, in terms of cosmetic appearance and weld integrity. Through the FriSC programme, TWI was able to offer Endoenergy the opportunity to fabricate the panels using friction stirwelding. The scope of the work included:
- Designing the end-cap joint
- Determining the tool design and welding parameters suitable for the fabrication
- Designing the fixture for holding the assembly during welding
- Completing welding trials
- Testing the welded panels
- Continued support after the completion of the programme, including provision of the process parameters required to produce satisfactory welds.
Success at each stage of the work showed Endoenergy that friction stir welding is a viable alternative for the panel fabrication with several advantages over TIG welding. These included ease of automation, fabrication speed, minimalcosmetic post weld finishing operations and appearance of the finished weld.
The FriSC programme, supported by the European Regional Development Fund, South Yorkshire Objective 1 and Yorkshire Forward allows TWI to provide free and subsidised technical support to small and medium sized companies in theYorkshire and Humber region, which, in the case of Endoenergy, equated to a £15 000 product development programme.
If you think your company could benefit from similar assistance, please contact TWI Technology Centre (Yorkshire) on 0114 269 9046.
