Local Vacuum technology – EBFLOW offers the possibility of eliminating the need for a vacuum chamber and has been developed by CVE for the joining of large structures particularly aimed at the renewable energy generation sectors. This technology has been demonstrated to weld thick sections up to 250 mm in steels and light alloys.
EBFLOW main advantages:
- Achieving the fastest thick section welding rates ever
- Facilitating very high joint completion rates in thick section steels
- A coarse vacuum is established and maintained only where it is needed
- Pre-heating is not necessary and consumables are not required during the weld
- Quality and reliability are improved with immediate post weld inspection possible
- 20 to 30 times faster than conventional submerged arc welding, 100mm per minute in 150mm thick steel have been achieved
- Using a system of sliding seals and precision handling enables fast longitudinal and circumferential welds on large work pieces
- There is no filler wire, the autogenous weld can be heat treated and the weld rendered invisible. It cannot be found using most methods of QC.
The Local Vacuum nature of EBFLOW is particularly suitable for large tubular thick section material. Welds can be made in a fraction of the time – over 20 times quicker than conventional arc welding methods is not unusual.
|Linear seam 1.3meters x 60mm WT||6.0 mins||8.3hrs||31 hrs||41 hrs
|Circular seam 711mm dia x 40mm WT||3.5 mins||5.0 hrs||47 hrs||63 hrs|
Tubulars – Wind Farms and Oil/Gas exploration
Technological innovation in this sector is being driven by the desire to reduce the costs and increase the manufacturing rate of large tubular structures used in tower foundations and offshore rigs of all types.
- Typically 90 meters long, 9 meters in diameter with 100mm wall thickness, weighing 1,200 tonnes.
- EBFLOW process particularly suited for wall thickness above 40mm and up to 200mm.
- 3,300 hrsSub Arc Weld: 60 meters long x 6 meters diameter, 80mm thick section.
- 110 hrsEBFLOW system: 60 meters long x 6 meters diameter, 80mm thick section.
Wind Tower flanges
EBFLOW Technology is being deployed to manufacture flanges from sections rather than forging the whole flange in one piece.
- Towers for wind energy are made from tubulars joined end on end.
- Flanges added to the ends of the tubulars are used to join them together.
- Forgings can be welded and, because there’s no filler wire, the autogenous weld can be heat treated and the weld rendered invisible. It cannot be found using most methods of QC.
Nuclear – Power Generation and Waste Containment
Modern nuclear power plants rely on the use of large tubular structures to contain high pressure water for cooling and for long term storage of waste.
- These forgings can also be welded with no filler wire, the autogenous weld can be heat treated and the weld rendered invisible. It cannot be found using most methods of QC.
- High integrity autogonus welds and near parent metal strength.
- Production is quicker, more cost effective and less reliant on a small number of manufacturers so easing a production bottleneck.
EBFLOW Vs Submerged Arc
Multiple Submerged Arc Welds (SAW) Vs a single pass EBFLOW.
- No joint “V” preparation required just clean metal to metal.
- Wide range of materials can be successfully welded.
- Single pass weld compared to a multi pass conventional arc weld.
For More Details:
Cambridge Vacuum Engineering
Tel: +44 (0) 1223 863481
Fax: +44 (0) 1223 862812
REFERENCE : http://www.camvaceng.com/new-technologies/reduce-pressure