Title

HIGH CONTAINMENT SPLIT BUTTERFLY VALVE Technical field

[0001] The present invention belongs to the technical field of valves and in particular, but not exclusively, to the technical field of valves used to regulate and intercept the flow of powdery products along transfer ducts. [0002] More specifically, the present invention belongs to the technical field of valves, whose rotor is of the butterfly type that can be split into two half-valves. In this field, usually one half-valve includes the actuation means and is called active half-valve, while the second half- valve is called passive half-valve because it is driven by the first half-valve.

[0003] These valves are usually installed in between the ends of two pipes, and both half-valves are shaped so that when the valve is disassembled, they are able to keep the end of the respective pipe closed and sealed.

[0004] In particular, the present invention is a decom posable high containment butterfly valve; the term contain ment refers to a series of measures taken for the purpose of limiting the diffusion of a particular substance for example to protect the process environment including operators. Present status of the art

[0005] Research to provide effective treatments for se rious diseases has led scientists over the years to develop drugs with increasingly powerful active ingredients, the so- called HPAPI (Highly Potent Active Pharmaceutical Ingredi ents), these drugs are very active and to be managed require high containment facilities, in order to safeguard first of all the health of operators employed in the production phase, but also to prevent cross-contamination and thus preserve product quality.

[0006] In some industries, such as in the pharmaceutical or biotechnology sectors, valves need to be made sterile before use and kept sterile during operation and product transfer.

[0007] Disassembling the valve is problematic for main taining sterility because it exposes to the outside world portions of the valve that would then come into contact with the product if the valve were reassembled, compromising both the sterility of the product and the sterility of the entire duct in which the valve is installed.

[0008] It should also be pointed out that decomposing the valve would cause some of the product to end up outside the transfer duct, with obvious risks given the type of product. [0009] Furthermore, at the end of each product transfer process, the entire transfer duct must be thoroughly cleaned, to reduce the risk of contamination between different prod ucts as much as possible.

[0010] Patent EP1996840 discloses a decomposable butter fly valve comprising two half-valves, which are complemen tary to each other and conformed so that the first half valve hermetically engages and cooperates with the second half-valve. Each half-valve includes a half-body, in which a seat for a half-rotor is provided, said half-rotor being conformed as a half-butterfly with a disc element, movable between a first open position in which the disc of the half rotor is not engaged with the seat and a second closed po sition in which the disc of the half-rotor is tightly engaged with the seat.

[0011] The coupled valve can take on two different oper ating configurations. In the first configuration the two half-bodies are reciprocally hermetically engaged and both discs of the two half-rotors are hermetically engaged in their respective seats, but they are not reciprocally engaged because they are detached so that with the two half-bodies joined, they form a chamber sealed to the outside. In the valve body, formed by the two half-bodies, an inlet and an outlet are defined, which serve to flush the chamber itself with a sterilizing fluid.

[0012] In the second configuration, the disks of the two half-rotors are reciprocally engaged and move together, passing from the first open position to the second closed position and vice versa.

[0013] A third configuration is that of the split valve, with the two half-bodies completely disengaged from each other.

[0014] The first configuration allows the cleaning of the valve from the product and the sterilization of the valve before disassembling it and, after the reassembly of the two half-valves, it allows the sterilization of the portions that have come into contact with the outside world before they come into contact with the product.

[0015] In the device described in EP1996840, a first male half-body, whose external surface is conformed as a cylin der, engages slidingly inside a corresponding cylinder de fined in the second female half-body; in the first operative configuration, the sealing towards the outside is obtained by means of a gasket ring circumferentially interposed be tween the two cylindrical surfaces respectively defined in the two half-bodies.

[0016] This configuration allows the centering of the two half-bodies, but defines tubular recesses that are very dif ficult to clean by flushing, thus permitting the diffusion of the product in the environment and compromising the con tainment of the valve. Objects and summary of the invention

[0017] It is an object of the present invention to provide a decomposable butterfly valve that can be easily coupled and split and at the same time reduces the width of the surfaces subject to getting dirty that must be cleaned, while also ensuring that the sterilizing flow can clean them easily and more effectively than in the known art.

[0018] This result is achieved with a decomposable but terfly valve which includes two bodies, each of which houses a dis-shaped half-rotor from which obliquely protrudes a half-shaft that rotationally engages in the corresponding half-body, the latter comprising a flange coupling with a corresponding flange of the other half-body.

[0019] A sealing seat is defined in the thickness of the coupling flange, which houses a toroidal gasket slightly protruding from the plane defined by the flange; when the two half-bodies are in contact, the respective gaskets touch each other and ensure the hermetic seal between the two half bodies, in addition, each of said gaskets ensures the her metic seal between the inside of the half-body and the disc of the respective half-rotor.

[0020] Both flanges of the valve half-bodies are embraced by an innovative clamping collar whose closing means, com bined with elastic contrasting means interposed between the two half-valves, allow the intermediate opening of the but terfly valve.

[0021] Compared to the prior art, the present invention includes an innovative sealing system that allows the valve to be split, minimizing the risk of contamination of the environment.

[0022] The fact that the disks of the half-rotors are hinged to the half-bodies by means of half-shafts with oblique axes of rotation makes it possible not to have sealing interruptions along the circumference of the flanges, and also makes it possible not to have a division even on the shaft, but only between the disks of the half rotors; this brings considerable advantages in terms of valve retention because in the present invention the half-shafts of the half-rotors protrude from the internal portion of their respective valve bodies without any coupling between them, making it much easier to contain the powders inside the valve.

Brief description of the drawings

[0023] Fig. 1 shows a top view of the assembled valve. [0024] Fig. 2. shows a side view of the assembled valve. [0025] Fig. 3 shows a longitudinal section of the assem bled valve, without the actuation means (18), according to the A-A plane shown in Fig. 1.

[0026] Fig. 4 shows a perspective view of the split valve; the elastic contrast means (4) are not shown.

[0027] Fig. 5 shows a section of the active half-valve only (1) according to the B-B plane shown in Fig. 3.

[0028] Fig. 5 shows a section of the passive half-valve only (2) according to the C-C plane shown in Fig. 3. Detailed description of an embodiment of the invention [0029] In the embodiment represented in the figures, the present invention comprises a butterfly valve of the type decomposable into two half-valves, the first half-valve (1) is commonly referred to as active because it is connected to actuating means that control the opening and closing of the valve; the second half-valve (2) is referred to as passive because it receives motion from the first half-valve.

[0030] Each half-valve comprises a valve half-body (11, 21) that houses a respective disc-shaped half-rotor (12, 22) rotationally connected to its half-body by means of a single half-shaft (15, 25) that protrudes obliquely from the disc of the respective half-valve and engages in a corresponding obliquely defined housing in the corresponding half-body. [0031] Each half-body comprises a coupling flange (13, 23) which has a protruding perimeter edge; in the thickness of the flange is defined the sealing seat of the disk of the half-rotor and the seal between the half-body and the disk of the corresponding half-rotor is obtained thanks to a to roidal gasket (14, 24), which protrudes slightly from the plane defined by the coupling flange.

[0032] Basically, the toroidal gaskets (14, 24) ensure a tight seal between each half-body and the disc of the re spective half-rotor, but they also cooperate with each other to ensure a tight seal between the two half-bodies when the latter are pushed against each other by the action of a clamping collar (3) that embraces the peripheral edges of both coupling flanges; the clamping collar comprises closing means (31) with three positions, to which correspond as many different configurations of the butterfly valve.

[0033] The first one is a washing configuration, in which the two half-bodies (11, 21) are reciprocally engaged and the seals (14, 24) counteract each other, ensuring the her metic seal of the valve; in this first configuration the disks (12, 22) of the two half-rotors are engaged in their respective seats and close the passage of the product, but they are not reciprocally engaged because they are kept apart by the action exerted by appropriate elastic contrast means (4), so that the disks of the two half-rotors in closed position and the two half-bodies joined together form an externally sealed chamber in which the washing fluid can flow in and out through inlet/outlet holes defined in the half-bodies .

[0034] The second one is the working configuration, in which the two half-bodies (11, 21) are reciprocally engaged, the gaskets (14, 24) contrast each other hermetically, and the discs (12, 22) of the two half-rotors are opposed in reciprocal contact; the latter rotate together, passing from the first opening position to the second closing position and vice versa.

[0035] The third one is a split configuration, in which the two half-bodies are disengaged from each other and the gaskets (14, 24) are not in contact with each other.

[0036] According to a particularly complete embodiment, each half-valve comprises reciprocal centering means to fa cilitate coupling with the other half-valve; shown in the figures are two pins (17) that protrude orthogonally from the plane defined by the coupling flange (11) of the half body of the active half-valve (1) and engage in two corre sponding holes (27), defined in the coupling flange (21) of the half-body of the passive half-valve (2).

[0037] In a preferred embodiment, each half-valve (1, 2) comprises means for locking (16, 26) the rotation of the respective half-rotor when the disc of the latter is not reciprocally in contact with the disc of the other half rotor.

[0038] In the embodiment shown in the figures, the lat eral surfaces of both half-shafts (15, 25) comprise an in termediate portion along which lateral flattenings are de fined which lie in planes orthogonal to the plane of the half-rotor disc, so that when the latter is in the closed position, with the disc engaged in the sealing seat, these flattenings are parallel to the longitudinal axis of the valve; on the side of each flattening is housed a respective piston having a variable section, with a distal portion thinner than the proximal portion.

[0039] In the washing configuration and in the split con figuration, when the half-bodies are in reciprocal contact with each other, the distal end of each piston protrudes from the plane of the coupling flange of the half-body thanks to the action of a helical spring that presses on the prox imal end, in this position the proximal, less thin portions of both pistons are in contact with one of the lateral flat tenings of the half-shaft and prevent the rotation of the latter and of the entire half-rotor.

[0040] Instead, when the flanges of the half-bodies are in mutual contact, i.e., when the valve is in the working configuration, the flange of each half-body compresses the springs of the pistons of the other half-body and makes them slide until the flattenings of the half-shafts are flanked by the thin portions of the pistons, which no longer block the rotation of the half-shafts of the half-rotors.