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EP-4528098-B1 - PRESSURE REDUCTION STATION FOR A HYDRAULIC NETWORK

EP4528098B1EP 4528098 B1EP4528098 B1EP 4528098B1EP-4528098-B1

Inventors

  • ROTA, Fortunato

Dates

Publication Date
20260513
Application Date
20240731

Claims (10)

  1. Pressure reduction station (100) for a hydraulic network comprising: - a Kaplan turbine (1) comprising: - a tubular body (2) defining at least in part a development axis (2a) along which a flow of fluid is conveyed and including at least one inlet (20) and one outlet (21) available in fluid passage connection with a hydraulic network (101) external to said turbine (1); - means of deflection (3) configured to deflect said fluid flow; - a propeller (4) arranged downstream of said deflection means (3) and configured to rotate about said development axis (2a) relative to said fluid flow and including - a shaft (40) extending along said development axis (2a), and - a plurality of blades (41) loosely connected to said shaft (40), distributed around said development axis (2a); - a hydraulic network (101) including: - an inlet duct (11) in fluid passage connection with said inlet (20), - an outlet duct (12) in fluid passage connection with said outlet (21); - said hydraulic network (101) further comprises an auxiliary duct (10) in fluid passage connection with said inlet and outlet ducts (11, 12) parallel to said turbine (1) and including a bypass valve (10a); and characterised by the fact that - said means of deflection (3) are positioned on said body (2) and including a plurality of stator deflectors (30) distributed around said development axis (2a): - said plurality of blades (41) are configured to rotate simultaneously around a respective inclination axis (41a) radial to said development axis (2a) to vary in flow rate and/or pressure said fluid flow determining variations of said fluid flow; - said bypass valve (10a) is configured to be actuated proportionally to said variations of said fluid flow imposed by said turbine (1) to maintain flow rate and/or pressure surges determined by said variations of said fluid flow within predetermined limit values.
  2. Station (100) according to claim 1, wherein said bypass valve (10a) is a hydro-valve or a needle valve.
  3. Station (100) according to any of the previous claims, wherein said auxiliary duct (10) comprises a first isolation gate valve (10b) arranged upstream of said bypass valve (10a) and a second isolation gate valve (10c) arranged downstream of said bypass valve (10a).
  4. Station (100) according to any of the previous claims, wherein said inlet duct (11) comprises a butterfly valve (11a) disposed upstream of said turbine (1) and configured to allow or obstruct the passage of said fluid flow exclusively to said turbine (1).
  5. Station (100) according to the preceding claim, wherein said butterfly valve (11a) is of the double eccentric type with an electric actuator provided with a fail-safe closing function.
  6. Station (100) according to any of the previous claims, wherein said outlet duct (12) comprises a third isolation gate valve (12a) arranged downstream of said turbine (1) and configured to allow or obstruct the passage of said fluid flow exclusively from said turbine (1).
  7. Station (100) according to claims 3 and/or 6, wherein one or more of said isolation gate valves (10b, 10c, 12a) is of a manual type.
  8. Station (100) according to any of the previous claims, wherein hydraulic network (101) comprises a vent valve disposed at said outlet duct (12) and configured to allow evacuation of said fluid from said hydraulic network (101) when the flow rate of said fluid flow exceeds a predetermined threshold value.
  9. Station (100) according to any of the previous claims, wherein said hydraulic network (101) comprises an overpressure valve disposed at said outlet duct (12) and configured to allow evacuation of said fluid from said hydraulic network (101) when the pressure of said fluid flow exceeds a predetermined threshold value.
  10. Station (100) according to any of the previous claims, comprising control means operatively connected at least to said blades (41) and to said bypass valve (10a) and configured to actuate said bypass valve (10a) in proportion to a rotation of said blades (41) around said respective inclination axis (41a) or vice versa.

Description

This invention relates to a pressure reduction station for a hydraulic network of the type specified in the preamble of the first claim. In particular, this invention relates to a pressure reduction station for a hydraulic network that allows the water flow within the network to be stabilised, especially by avoiding large pressure surges. A similar station is described in patent application WO 2014/012150 A1. As is well known, there are numerous in-line pressure reduction points in aqueduct networks, which are necessary so that the water reaches the end user with a controlled flow and pressure. To this end, a pressure control valve is installed at each reduction point, whose function is basically to dissipate excess pressure, and thus energy. This 'excess' is potentially convertible into electricity that can be directly exploited or sold to the electricity grid operator. At present, this potential has already been at least partially exploited by installing at these points expensive, custom-built hydraulic turbines or pumps, which, installed in place of the turbine, have an inverse function to the conventional operation of commercial pumps and only achieve very low efficiencies. Although solutions involving the adoption of a turbine at the reduction points allow higher efficiencies to be achieved during certain operating transients, these solutions have, like pump solutions, the great disadvantage of having a significant impact on hydraulic networks, as they can cause impulsive phenomena, such as 'water hammers', which are potentially destructive to the piping. In this situation, the technical task underlying this invention is to devise a pressure reduction station for a hydraulic network capable of substantially overcoming at least part of the aforementioned drawbacks. In the context of said technical task, it is an important purpose of the invention to obtain a pressure reduction station for a hydraulic network which allows drastically reducing the formation of impulsive phenomena such as water hammers. Therefore, another important purpose of the invention is to achieve a pressure reduction station for a hydraulic network which allows to reduce the wear and the possibility of breakage of the pipes composing the hydraulic network. In conclusion, a further purpose of the invention is to realise a pressure reduction station for a hydraulic network allowing to stabilise the pressure of the fluid arriving at the users. The specified technical task and purposes are achieved by a pressure reduction station for a hydraulic network as claimed in the annexed claim 1. Preferred embodiments are highlighted in the dependent claims. The characteristics and benefits of the invention will be clarified in the following detailed description of some preferred embodiments of the invention, with reference to the accompanying drawings, wherein: Fig. 1 shows a longitudinal cross-section view of a Kaplan turbine according to the invention;Fig. 2 shows a perspective view of a first embodiment of a Kaplan turbine blade according to the invention;Fig. 3 is a side view of the blade in Fig. 2;Fig. 4 shows a perspective view of a second embodiment of a Kaplan turbine blade according to the invention;Fig. 5 shows a perspective view of a pressure reduction station for hydraulic network according to the invention;Fig. 6 shows a top view of a pressure reduction station for hydraulic network according to the invention;Fig. 7 is a side view of a pressure reduction station for hydraulic network according to the invention; andFig. 8 shows a front view of a pressure reduction station for hydraulic network according to the invention. In this document, when measurements, values, shapes, and geometric references (such as perpendicularity and parallelism) are associated with words like "approximately" or other similar terms, such as "almost" or "substantially", they shall be understood as except for errors of measurement or imprecisions due to errors of production and/or manufacturing and, above all, except for a slight departure from the value, measurement, shape, or geometric reference with which it is associated. For example, if associated with a value, such terms preferably indicate a departure of no more than 10% of the value itself. Moreover, when used, terms such as "first", "second", "higher", "lower", "main" and "secondary" do not necessarily identify an order, a priority of relationship or a relative position, but can simply be used to clearly distinguish between their different components. Unless otherwise specified, as reflected in the following discussions, terms such as "processing", "computing", "determination", "computation", or the like are considered to refer to the action and/or processes of a computer or similar electronic computing device that manipulates and/or transforms data represented as physical, such as electronic quantities of records of a computer system and/or memories, in other data similarly represented as physical