ITFI20120024A1 - INTERNAL WASHING DEVICE FOR PIPES AND VALVES. - Google Patents

Description

DESCRIPTION

Attached to the application for a PATENT FOR INDUSTRIAL INVENTION entitled:

INTERNAL WASHING DEVICE FOR PIPES AND VALVES

Technical field

The present invention belongs to the sector of pipes and valves used in systems for loading and unloading loose substances in powder, granules, capsules and the like, such as for example those handled in the pharmaceutical, chemical and food industries.

State of the art

In the chemical, food and pharmaceutical industries, bulk materials must often be handled through loading and unloading systems that include special pipes, the latter can be equipped with accessories, such as, for example, shut-off valves.

In many cases it is necessary that said bulk materials are handled in such a way as to avoid or reduce any contact with the outside, both to avoid contaminating the material and to avoid dispersion of the bulk materials into the environment.

The problem of keeping the inside of the pipes clean is also felt, and even more the problem of cleaning those parts of the loading and unloading system that can come into contact with both the conveyed material and the external environment.

Systems have been developed, such as the one described in EP 1550833 A2, which consists of a sleeve, to be mounted between two butterfly valves, equipped with special means for introducing and extracting a washing liquid by means of suitable ducts, the liquid inlet duct, in particular, having a spray head, while the extraction duct can be oriented in order to be positioned as close as possible to the valve that closes the lower part of the sleeve.

The solution described above has some disadvantages, in particular the jets of the spray head are static and therefore do not sweep the entire internal surface of the sleeve, furthermore the small holes in the spray head inevitably come into contact with the substances passing through the duct, easily risking finally, the spray head remains permanently inside the sleeve, constituting an obstacle to the flow of the material.

Directional washing liquid outlet heads have also been developed, thus able to sweep with their jets with greater continuity than fixed spray heads.

In particular, EP 1574762 A2 and EP 1604747 A2 show a washing device comprising an orbital type outlet head, which, rotating under the thrust of the washing liquid, is able to direct its jets according to all directions of the surface. orthogonal to the rotation axis of the head, so as to continuously sweep a circumference inside the pipe. Furthermore, the orbiting head of the washing device described in EP 1604747 A2 is mounted at the end of a movable arm, also rotating around its own axis, through which the head can translate towards the center line of the pipeline when washing is to be carried out and can be withdrawn near a wall during the flow of the material, positioning itself in a partially recessed position, so as to reduce the protrusion of the head inside the conduit.

The solution with a double orbit head, rotating around two axes, if it allows to cover the entire solid angle for 4Ï steradians, is however very complex to make and delicate to use; requiring the use of complex kinematics and motorized drive systems.

Furthermore, even in these cases, the small holes from which the washing liquid comes out can come into contact with the bulk material, becoming clogged.

Aims and summary of the invention

The purpose of the present invention is therefore to provide a washing device which is simple, economical and robust in construction and which, at the same time, overcomes the limits of the previously described findings, being able to provide an effective internal washing without needing to be motorized.

This and other purposes are achieved by means of a washing device comprising a casing consisting of a socket (2) equipped with a side sleeve (21), with a washing tube (1) slidingly coupled to the inside of said side sleeve (21) ).

The end (11) of said tube (1), external to the casing, is connected to a hydraulic circuit for feeding the washing fluid, while the other end of said tube (1), inside the casing, has a plurality of nozzles (3) arranged circumferentially, with an impeller (4) covering some of them.

The impeller (4) is only free to rotate around the axis of said tube (1) and has profiles shaped like the motions of a cylindrical cam, so that the nozzles are partly covered and partly uncovered.

When the pressurized fluid is inserted inside the tube (1), it then exits the nozzles (3) with high speed and if a nozzle is partially covered by the impeller profile (4) the jet impacts against the profile, with the consequence that its trajectory is modified and that an energy transfer takes place to the impeller, which rotates, it is thus while some nozzles are discovered, others are covered.

In this way, due to the impact with the impeller profile (4), the jets of washing liquid are forced to continuously vary their direction and thus hit the entire internal surface of the stub pipe (2) , including the side bases where butterfly valves or other devices are normally positioned, useful both for the interception of the material and for other purposes. A particularly accurate version of the invention provides that, in order to increase the rotation effect of the impeller and the deflection of the jets, the internal lateral surface (43) of the impeller (4) and the surface of at least one of said end profiles (41, 42) are joined by means of substantially frusto-conical surfaces (44, 45).

The impact of the washing liquid jets on said inclined connecting surfaces (44, 45) increases the energy transfer effect to the impeller (4) and at the same time varies the direction of the jets themselves, which sweep the € ™ entire internal surface of the log (2).

Another purpose of the present washing device is to leave the entire section of passage of the material free, thus without minimally cluttering the stub during normal loading / unloading operations. This is to avoid obstructing the passage and to prevent the nozzles from clogging due to loose material. This further object has been achieved by providing for the possibility of retracting the washing tube from the advanced working position to a retracted rest position.

To improve insulation, special sealing means (22) are interposed both towards the outside and vice versa between the external surface of the pipe (1) and the internal surface of the sleeve (21).

The internal end of the washing tube (1) is equipped with a projection (12) which serves both to prevent the tube (1) from slipping off the coupling (21) and to adhere, during tube extraction (1), to an annular surface (6) placed in a slightly backward position with respect to the internal side wall of the socket, thus completely isolating the device both from the flowing material and from the external environment.

Advantageously, said annular surface (6) can be made on the internal part of said sealing means (22), the latter can be made using a polymeric material which guarantees both impermeability and smoothness.

To improve the insulation between the annular surface (6) and the projection (12), a toroidal gasket (62) can be interposed.

Brief description of the drawings

- Fig. 1 shows an axonometric view of the present invention, with the washing tube (1) in the advanced working position.

- Fig. 2 shows an axial section of the stub pipe (2), of the lateral sleeve (21) and of the sealing means (22) of the present washing device; the washing tube (1), with the projection (12) and the impeller (14) are left visible. The annular surface is also partially visible (6).

- Fig. 3 shows a more detailed view of the end of the tube (1), inside the casing; the projection (12), the nozzles (3), the impeller (4) are visible. In the embodiment shown in figure no. 3 the toroidal gasket (62) is provided, interposed between the annular surface (6) and the projection (12). In figure n. 3 The trace of the section plane A-A was also indicated.

- Fig. 4 shows section A-A of the present washing device.

- Figures n. 5, no. 6, no. 7 and n. 8 represent a series of detail views of the end of the tube (1), inside the casing; in each of the cited images a possible position is shown that can be assumed by the impeller (4) around the axis of said tube (1). In figure n. 5 the trace of the section plane B-B is shown, in figure n. 6, the trace of the section plane C-C, in figure n. 7, the trace of the section plane D-D and finally in figure n. 8 The trace of the section plane E-E is indicated.

- Figures n. 5a, n. 6a, n. 7a and n. 8a represent respectively the section B-B, the section C-C, the section D-D, and the section E-E of the present washing device.

Detailed description of an embodiment of the invention

The internal washing device for ducts, object of the present invention, comprises a washing pipe (1), which slides inside a sleeve (21) placed on the side wall of a stub pipe (2) and movable between an advanced position of work and a backward position of rest.

Conveniently said sleeve (21) can be of the unified type, as well as the socket (2). One of the main advantages in adopting unified elements is the possibility of using standard locking means to join them together.

The end (11) of said pipe (1), which is located externally to the casing made up of the socket (1) to which the sleeve (21) is fixed, has means for connection to a hydraulic supply circuit, while the other end of said tube (1), inside said socket (2), has a plurality of nozzles (3) arranged so as to describe at least one circumference.

In a preferred embodiment of the invention the nozzles are arranged so as to describe two adjacent circumferences.

Whether the nozzles describe a single circumference or form more than one, some of them are partially covered by an impeller (4) which is only free to rotate around the axis of said tube (1). Said impeller (4) has at least one of the two end profiles (41, 42) shaped like the motive of a cylindrical cam delineating one or more ramps, each of which always covers at least two consecutive nozzles.

When the nozzles (3) are arranged according to two circumferences (31, 32) each of the end profiles (41, 42) of said impeller (4) delineates at least one ramp. The inclination of the ramps is such that, when the impeller (4) rotates, all the ramps have the same growth or lowering trend towards the outside at the same time.

Advantageously, the internal lateral surface (43) of said impeller (4) and the surface of at least one of said end profiles (41, 42) are joined together by means of substantially frusto-conical surfaces (44, 45).

When a pressurized fluid is introduced into the pipe (1), it happens that a jet of fluid comes out at high speed from each single nozzle, whether it is completely or partially free.

The jets that come out of the free nozzles continue their run according to a substantially rectilinear trajectory until the moment of impact with the surface to be washed; otherwise the jets that come out of partially covered nozzles impact against the profile of the impeller ramp, thus deviating their trajectory and transferring part of their energy to the impeller which is set in rotation. The deviation of the trajectory ensured by the impact with the impeller guarantees the change in the direction of the liquid jets, so as to reach all the internal areas of the stub, both the side surfaces and the base surfaces.

To increase the effect of transferring energy from the jets to the impeller (4) and deviation of the trajectory of the jets, the internal lateral surface (43) of the impeller (4) and the surface of at least one of the said end profiles (41, 42) can be joined by means of substantially frusto-conical surfaces (44, 45).

According to a preferred embodiment of the invention, the nozzles (3) are arranged radially and are perpendicular to the axis of the washing tube (1).

To ensure the necessary insulation between the inside of the casing and the outside, the sliding coupling between said washing pipe (1) and said sleeve (21) takes place through the interposition of a seal (22) .

In order not to obstruct the flow of the material in the socket and not to risk obstruction of the nozzles, the tube (1) is placed in the advanced working position only for the time necessary for washing, while during the flow of the material to the inside the stub pipe, the tube (1) runs outwards, in order to leave the passage section of the material clear.

Advantageously, the end of said washing tube (1) inside said stub (2) is blind and forms an anti-slipping circular projection (12) having an external diameter greater than that of the part of said washing tube slidingly coupled to said sleeve (21).

The projection (12) prevents the tube (1) from being completely extracted during the transition from the forward working position to the rear rest position, due to incorrect maneuvers.

A simple and economical constructive form of said circular projection (12) foresees the use of a cap (12) which also serves to close the internal end of the tube (1).

In a slightly rearward position with respect to the side wall of said stub (2), there is an annular surface (6) coaxial with said washing tube (1). When the washing tube (1) moves back towards the rest position said projection (12) comes to approach said annular surface (6); the seal between the projection (12) and the annular surface (6) can be improved by interposing between the two toroidal gaskets (62); in this way the entire device remains isolated both from the flowing bulk material and from the external environment.

For convenience, the annular surface (6) can be made directly on the seal (22).

Claims (10)

CLAIMS 1. Internal washing device for ducts, comprising a washing pipe (1), slidingly coupled inside a sleeve (21) placed on the side wall of a stub pipe (2) and movable between an advanced working position and a back rest position; the external end (11) of said tube (1) having means for connection to a hydraulic supply circuit and the end of said tube (1) internal to said stub (2) having a plurality of nozzles (3 ), characterized by the fact that said nozzles (3) are arranged circumferentially and some of them are covered by an impeller (4) which is only free to rotate around the axis of said tube (1). 2. Washing device as per the preceding claim, characterized in that said impeller (4) has at least one of the two end profiles (41, 42) shaped like the motive of a cylindrical cam delineating one or more ramps. 3. Washing device as per one or more of the preceding claims, characterized in that each of said one or more ramps always covers at least two consecutive nozzles (3). 4. Washing device as per one or more of the preceding claims, characterized in that said nozzles (3) are arranged along two circumferences (31, 32) and each of the end profiles (41, 42) of said impeller ( 4) delineates at least one ramp and that, when said impeller (4) rotates, all said ramps have at the same time the same growth or lowering trend towards the outside; 5. Washing device as per one or more of the preceding claims, characterized in that the internal lateral surface (43) of said impeller (4) and the surface of at least one of said end profiles (41, 42) are connected by means of substantially frusto-conical surfaces (44, 45). 6. Washing device according to one or more of the preceding claims, characterized in that said nozzles (3) are arranged radially and are perpendicular to the axis of said washing tube (1). 7. Washing device as per one or more of the preceding claims, characterized by the fact that the end of said washing tube (1) inside said stub (2) is blind and forms an anti-slip circular projection (12) having an external diameter greater than that of the part of said washing tube slidingly coupled to said sleeve (21). 8. Washing device as per one or more of the preceding claims, characterized in that the sliding coupling between said washing tube (1) and said sleeve (21) takes place through the interposition of a seal (22) . 9. Washing device as per one or more of the preceding claims, characterized in that, in a slightly rearward position with respect to the side wall of said stub (2), there is an annular surface (6) coaxial with said washing pipe (1), which approaches said projection (12) when the washing tube (1) is in its rearward rest position, sealing it by means of an interposed toroidal gasket (62). 10. Washing device as per one or more of the preceding claims, characterized in that said annular surface (6) is formed on said seal (22).