Francis hydraulic turbines
Clockwork spinning precision
Invented by James B. Francis in 1849, Francis turbines are the most popular and wide-spread runner worldwide, in addition to being among the first Hydroelectric turbine designs to be ever created.
Unlike the Pelton runner, Francis is considered a reaction turbine, since it creates energy through water pressure instead of kinetic power.
Francis runners work completely immersed in water; one of their key characteristics is the fact that they change the water’s direction as it flows through the turbine.
The water flow enters the turbine in a radial direction, flowing towards its axis, but after hitting the turbine’s blades it exits along the direction of said axis, for this reason the Francis is also called a “mixed flow turbine”.
The runner is placed inside a special casing called “volute”, which resembles a spiral or snail shell, to make sure water hits it from the perfect angle.
This kind of turbine is usually installed in sites with medium head and flow, as well as being capable of working both vertically and horizontally depending on its application.
Top-tier precision is what makes our turbines stand out; our 3D dimensional report proves it further.
Thanks to our experience and lean model of production we have reached excellent levels of accuracy: the great majority of runners we balance do not require any additional material removal, thus saving precious lead time and guaranteeing top-notch wheel quality, as well as a longer expected lifetime.
Throughout all steps of production, from raw material to finished product, our quality standard ensure that all technical requirements are met. If requested by the customer, we can supply a template kit for dimensional control.
When it comes to production, the Francis turbine takes the longest to manufacture, therefore, using our experience and cutting-edge technologies, we have developed a range of technical solutions that simplifies their manufacturing process resulting in lower lead time, even with complex geometry pieces.
For instance, 2 halves of a turbine can be manufactured and welded together.
If needed, we can surface coat (ex. Tungsten carbide) our Francis Turbines to improve the surface toughness of parts most effected by wear.
Aluminum 1.4313 or 1.4417 is used to ensure optimal structural integrity and reduce time spent on repair and maintenance.
As of today, we have a portfolio of more than 300 turbines manufactured.
NON DESTRUCTIVE TESTING
Every turbine manufactured undergoes NDT testing: a series of tests to check a products’ structural integrity, welding defects and surface cracks.
DYNAMIC AND STATIC BALANCING
Turbine’s balance is essential, and it must be tested still and in motion to point out asymmetries and undistributed weight that might stress the bearing, thus increasing the wheel’s expected lifespan.
High quality welding is performed by our skilled and experienced operators.
Should the project require it, thermal treatment is carried out by our external partners.
The CNC-worked surfaces are flattened and refined through manual polishing.
Get a free custom quotation