Wringing process for rolled strip and wringing installation

Abstract

TITLE: Wringing method for rolled strip and wringing installation The invention relates to a method for wringing a rolled strip (2) comprising: Advancing said strip (2) between at least one pair (3) of two wringing rollers (31, 32), performing a first wringing operation, allowing a residual layer of lubricant (Cr) to pass and a blocked layer (Cb) to accumulate; Projecting a fluid (4) from at least one blowing point (41) onto the strip (2) so as to project a part of said residual layer of lubricant (Cr) into a guide channel (66) between the wringing roller (31, 32) and the blowing box (64) and another part against at least one of the wringing rollers (31, 32) so that it adheres to a surface (S) of said wringing roller (31, 32); Return of the lubricant through the guide channel (66) and by rotation of said wringing roller (31, 32), the lubricant then falling back onto the blocked layer (Cb).The invention also relates to a spinning installation implementing such a method. Figure 3.

Description

Title of the invention: Spinning method for laminated strip and spinning installation Technical field

[0001] The present invention relates to industrial installations, in particular of the rolling mill type, using lubricant. Prior art

[0002] Rolling mills are industrial machines that allow a rolling operation to be carried out, which is a manufacturing process by plastic deformation of a strip of material, in particular metal. The strip, generally of small thickness compared to its length and width, is driven in translation and compressed between at least two rollers located on either side of the thickness of the strip. By this operation, the thickness of the strip is reduced, but also uniformized over the entire length of the strip.

[0003] Such an operation can be implemented at very high rates, which may involve very fast linear belt running speeds. The forces involved and these considerable speeds imply the use of very large quantities of lubricant. For example, a possible lubricant flow rate for such applications may be of the order of 1000 1 / min. Reference is made to "lubricant", but it is understood that this term designates a liquid which can fulfill both lubrication and cooling functions.

[0004] Two different types of wringers can be distinguished for applications on such rolling mills: - A first type called "large rollers" (meaning large diameter) extremely rigid along its length, which, by its nature does not allow perfect contact to be obtained over the entire width of the strip and therefore allows a significant quantity of lubricant to pass through. Such an imperfection requires the use of blowers, but the expelled lubricant spurts out in an uncontrolled manner and the noise generated is considerable. However, such a solution is very robust, simple to implement and inexpensive. - A second type, called "small rollers" which are relatively flexible, capable of being slightly deformed by a plurality of counter-rollers on which a force is applied by jacks so that the small roller maintains perfect contact over the entire width of the strip, which allows the lubricant to be better blocked. However, such a solution is clearly more complex: it involves the control of multiple actuators which are expensive to manage in maintenance because the lubricant, then loaded with small metal particles, causes rapid wear of the counter-rollers. This second type of wringer has the disadvantage of being quickly flooded, that is to say that the lubricant can reach a level exceeding the height of the small roller, if it is used without a wringer with large rollers upstream because the counter-rollers quickly transfer the lubricant downstream or cause the formation of drops which fall on the belt.

[0005] The present disclosure aims to improve these two types of wringers, by providing a solution to resolve all or part of their drawbacks. Summary

[0006] According to a first aspect of the present disclosure, there is provided a method of dewatering a laminated strip comprising at least one layer of lubricant, the method comprising: - Advancement of said rolled strip between at least one pair of two squeezing rollers, from an upstream side to a downstream side, the upstream and downstream sides being delimited by the point of contact of each pair of squeezing rollers on the rolled strip, each squeezing roller being rotatable in the direction of advance of the rolled strip and performing a first squeezing operation by contact, allowing a residual layer of lubricant to pass on the downstream side and allowing a layer blocked by said pair of squeezing rollers to accumulate upstream; - Projecting a fluid from at least one blowing point onto the rolled strip so as to detach all or part of said residual layer of lubricant located downstream of the at least one pair of squeezing rollers, thus forming a flow of pressurized fluid circulating in a guide channel formed between a guide surface extending downstream from the blowing point towards upstream around said squeezing roller, bypassing said squeezing roller, and a cylindrical surface of at least one of the squeezing rollers, at least a part of said detached residual layer remaining in suspension in said flow of fluid and at least a part of said detached residual layer adhering to said cylindrical surface of at least one of the squeezing rollers; - Return of the residual layer of lubricant from downstream to upstream, a part of said layer of lubricant being returned by the flow of fluid circulating in said guide channel, another part adhering to said cylindrical surface being returned by the rotation of at least one of the squeezing rollers, the residual layer being returned to the blocked layer upstream of at least one of the squeezing rollers.

[0007] The features set out in the following paragraphs may, optionally, be implemented, independently of one another or in combination with one another:

[0008] The method may include removing all or part of the trapped lubricant layer beyond the side edges of the rolled strip.

[0009] The length of the squeezing roller may be greater than the width of the strip, the fluid being projected from the at least one blowing point in the form of at least one continuous fluid blade over at least the entire length of the squeezing roller, blowing through a gap between the rollers, beyond the width of the strip, the fluid blade being configured to prevent the passage of the blocked layer of lubricant located upstream of the squeezing rollers to the downstream side by passing through the gap between the squeezing rollers which exceed the width of the rolled strip.

[0010] The at least one continuous fluid blade can be obtained by projecting a fluid through at least one slot, said slot being formed by a clearance between two parts of an assembly forming a box, said slot obtained being continuous over at least the entire length of the wringer roller, and the two parts, once assembled, forming a plenum chamber supplied by a pressure source and opening onto said slot.

[0011] Preferably, the blowing point from which the fluid is projected is positioned in a zone, the zone extending downstream of the squeezing roller over at least the entire width of the rolled strip, the blowing point located at a distance from the point of contact between the roller and the strip of between 20mm and 70mm depending on the direction of the strip.

[0012] In other words, the blowing point can be positioned in a zone extending downstream of the squeezing roller over at least the entire width of the rolled strip, and over a length along the direction of the strip of 70 mm, the blowing point being positioned at least 20 mm from the point of contact between the roller and the strip along the direction of the strip.

[0013] According to one possibility, the squeezing roller being a cylinder with a radius in particular a diameter greater than 100 mm such as 150 mm, the blowing point from which the fluid is projected being positioned in a concave zone located between the squeezing roller and the rolled strip, the zone extending downstream of the squeezing roller over at least the entire width of the rolled strip, and over a length equal to the radius from the point of contact between the squeezing roller and the rolled strip.

[0014] According to a second possibility and in particular for rollers of smaller diameter, for example between 52mm and 63mm, or respectively with radii of 26mm and 31.5mm, the distance between the blowing point and the contact point can then be greater than the radius, for example equal to 32mm.

[0015] Generally speaking, the distance between the blowing point and the contact point, measured in the direction of travel of the strip, can therefore be between 20mm and 70mm, such as 47mm.

[0016] The at least one blowing fluid blade may be oriented at an angle of between 30° and 60° relative to the plane of the moving strip, the blade directed countercurrent to the moving strip, and so as to push the oil from downstream to upstream, towards the squeezing roller.

[0017] The guide surface can be obtained by an external shape of one of the two parts of said box.

[0018] The projection of the fluid can take place downstream of the two squeezing rollers of the at least one pair of squeezing rollers, on one side and the other of the rolled strip.

[0019] The blowing point can be positioned at a distance from the strip, in the direction normal to the strip, of between 1 mm and 10 mm such as 4 mm.

[0020] There is also proposed, according to a second aspect of the present disclosure, an installation for dewatering a rolled strip comprising at least one layer of lubricant, the dewatering installation comprising: - At least one pair of two squeezing rollers configured to allow the advance, between the two squeezing rollers of each pair, of said rolled strip from an upstream side to a downstream side, each squeezing roller being rotatable in the direction of advance of the rolled strip and being configured to perform a first squeezing operation by contact, the upstream and downstream sides being separated by the point of contact of the at least one pair of squeezing rollers on the rolled strip, each pair of squeezing rollers being configured to allow a residual layer of lubricant to pass on the downstream side and allowing a layer blocked by said pair of squeezing rollers to accumulate upstream; - At least one blowing point from which a fluid is projected configured to detach all or part of said residual layer of lubricant located downstream of the at least one pair of squeezing rollers, the squeezing installation comprising a guide surface extending from downstream from the blowing point towards upstream around said squeezing roller, bypassing said squeezing roller, each roller comprising a cylindrical surface, a guide channel being formed between said guide surface and said cylindrical surface, the projected fluid circulating in a fluid flow in the guide channel, at least a part of said detached residual layer of lubricant remaining in suspension in said fluid flow and at least a part of said detached residual layer of lubricant adhering to said cylindrical surface (S) of at least one of the squeezing rollers; - a part of said layer of lubricant being returned to the upstream side by the flow of fluid circulating in said guide channel, another part adhering to said cylindrical surface being returned by the rotation of at least one of the squeezing rollers, all or part of said residual layer of lubricant detached then accumulating on the upstream side on the blocked layer.

[0021] Generally, the installation can be configured to implement the method according to the present disclosure.

[0022] The features set out in the following paragraphs may, optionally, be implemented, independently of one another or in combination with one another:

[0023] At least one of the squeezing rollers may extend over at least the entire width of said laminated strip, said squeezing rollers being configured to at least partially evacuate the blocked layer by the lateral edges of the laminated strip.

[0024] The length of the squeezing roller may be greater than the width of the rolled strip and the fluid being projected in the form of a continuous fluid blade over at least the entire length of the squeezing roller, so as to prevent the passage of the blocked layer of lubricant located upstream of the squeezing rollers towards the downstream by passing through the space between the two squeezing rollers of a pair which exceed the width of the rolled strip.

[0025] The continuous fluid blade can be obtained by projecting a fluid through a slot, said slot being formed by a clearance between two parts of an assembly forming a box, said slot obtained being continuous over at least the entire length of said squeezing roller, and the two parts, once assembled, forming a plenum chamber supplied by a pressure source and opening onto said slot.

[0026] Said squeezing roller being a radius cylinder, the blowing point from which the fluid is projected being positioned in a concave zone located between said squeezing roller and the rolled strip, the zone extending downstream of the squeezing roller over at least the entire width of the strip, of a length equal to the radius from the point of contact between the squeezing roller and the rolled strip.

[0027] The guide surface can be obtained by an external shape of one of the two parts of said box.

[0028] The projection of the fluid takes place downstream of the two squeezing rollers of the at least one pair of squeezing rollers, on one side and the other of the rolled strip.

[0029] The installation may comprise a transverse beam and a cassette, removable from the transverse beam, in translation along a sliding connection between the cassette and the transverse beam in a direction parallel to the length of the wringing rollers, said cassette comprising one of the wringing rollers and said blowing point.

[0030] Said cassette comprising said box, said box can be formed by the assembly of the two parts, the plenum chamber as well as a fluid connection to a fluid circuit.

[0031] Said fluid connection being a quick coupling comprising a seal allowing said cassette to be uncoupled from said fluid circuit by a translation in the direction of said sliding connection.

[0032] Said sliding connection being obtained by cooperation between a roller holder fixed to the cassette comprising a plurality of rolling rollers, and a T-shaped groove arranged in the fixed transverse beam having at least one rolling surface configured to guide the plurality of rolling rollers in translation. Brief description of the drawings

[0033] Other characteristics, details and advantages will appear on reading the detailed description below, and on analyzing the attached drawings, in which: Fig.l

[0034] [Fig.l] shows a general view of a rolling mill equipped with a wringer according to one embodiment, Fig. 2

[0035] [Fig.2] shows a detailed view of a wringer according to an embodiment illustrating in particular the two wringing rollers, of large diameter (greater than 100mm), such as 150mm, articulated at their end. Fig. 3

[0036] [Fig.3] shows a detailed view of a spinning process according to a rea lization. Fig.4 and 5

[0037] [Fig.4] and [Fig.5] show a cassette according to one embodiment, Fig. 6

[0038] [Fig.6] shows a detailed view of a wringer box according to a method of rea lization. Fig.7 and 8

[0039] [Fig.7] and [Fig.8] show in detail the two parts of a wringer box according to a embodiment. Fig. 9

[0040] [Fig.9] shows a detailed view of a wringer box according to one embodiment illustrating in particular the distance between the blowing point and the point of contact with the strip following the direction of travel of the strip, which is typically less than the diameter of the squeezing roller for a large diameter roller. Fig. 10

[0041] [Fig. 10] shows in detail the two parts of a wringer box according to one embodiment, as well as the sliding connection allowing the extraction or insertion of the cassette to the transverse beam, said sliding connection comprising a T-groove, and a set of rollers rolling in a raceway of the groove. Fig. 11

[0042] [Fig. 11] is a sectional view of a second embodiment for which the squeezing rollers are of smaller diameter, typically with a radius of less than 50mm such as between 26mm and 31.5mm, the blowing point being located at a distance from the point of contact between the squeezing roller and the strip, greater than the radius of the roller, a plurality of rollers being distributed against the squeezing roller, on the side opposite the point of contact with the strip. Fig. 12

[0043] [Fig. 12] a graph representing on the ordinate the thickness of the oil layer, and on the abscissa the distance in the downstream zone to the point of contact, illustrating: - along a first curve (at the top, identified by crosses), the quantity of residual oil in the downstream zone of the strip, from the point of contact with the squeezing roller of a squeezing installation according to the state of the art, without blowing, - following a second curve (at the bottom identified by circles), the quantity of residual oil in the downstream zone of the strip, from the point of contact with the squeezing roller of a squeezing installation according to the present disclosure, provided with blowing and guide surface ensuring a return according to the present disclosure. Description of the embodiments

[0044] Reference is now made to [Fig. 1]. On the left-hand side of the figure is shown a rolling mill 10 with rollers. The two smallest rollers are the so-called "working" rollers, which are used to transmit a compressive force to the strip in order to reduce and standardize its thickness. The other so-called "intermediate" rollers have the function of preventing the deformation of the working rollers and transmitting the compressive force to them.

[0045] The present disclosure is suitable for dewatering a strip rolled by a rolling mill, which may be, for example, a 2, 4, 6, up to 20 roll mill as illustrated in [Fig.l], comprising: - a lower working cylinder and an upper working cylinder on either side of the rolled strip, - two first intermediate, lower cylinders, respectively in contact with the lower working cylinder and two intermediate, upper cylinders, respec- tively in contact with the upper working cylinder - three second intermediate cylinders, lower, in contact two by two, respectively with the first two lower intermediate cylinders, and three second intermediate cylinders, upper, in contact two by two, respectively with the first two upper intermediate cylinders, - four sets of lower support rollers, in contact two by two, with the three second lower intermediate cylinders, and four sets of upper support rollers, in contact two by two, with the three second upper intermediate cylinders.

[0046] The support roller assemblies are typically mounted with eccentric systems, which make it possible to ensure tightening of the strip, or even to ensure control of the cambering of the cylinders, including the cambering of the working cylinders.

[0047] By controlling the camber, it is possible to give a strip profile to the rolled strip, which can be straight, or often curved.

[0048] Such a rolling mill generally comprises four ramps for spraying lubricant, typically a mixture of oil and water, at the working rolls. In the embodiment shown in [Fig.l], two ramps are arranged in the upper part, on one side of the rolled strip 2, and two ramps in the lower part on the other side of the rolled strip 2. Each ramp comprises, along its length, transversely to the strip, a series of nozzles, ensuring spraying of lubricant over the width of the strip, and / or onto the rollers of the rolling mill.

[0049] The embodiments of the wringing installation 1 disclosed in the present document are not limited to being used only in the presence of a 20-roll rolling mill as shown [Fig.l], which is shown only as an example, but to any industrial installation of the type of strip rolling mills using lubricant.

[0050] The embodiments of the wringing installation 1 disclosed in the present document are not limited to being used only in the presence of a “large roller” wringer as shown [Fig.l], which is shown only by way of example, but to any wringer installation using rollers.

[0051] According to one embodiment, the strip 2 first passes through the rolling mill 10 and then passes through the dewatering installation 1, which defines a direction of advance V of the rolled strip 2, from an upstream side (from the rolling mill) to a downstream side (after each pair of rollers 3 of a dewatering installation).

[0052] In an embodiment shown [Fig.l] as a non-limiting example, the wringing installation shown comprises two pairs of rollers 3 arranged one after the other, per stage, to increase the wringing efficiency.

[0053] The squeezing rollers may be cylindrical. The rollers may also have a non-cylindrical profile, in particular convex and / or concave, for both Wringing rollers. A wringing roller profile is chosen which is shaped, as much as possible, to the profile of the strip rolled by the rolling mill. Such a profile adaptation increases the wringing efficiency of the rollers, by limiting the gaps, promoting the passage of a residual layer of lubricant.

[0054] Generally, the pair or pairs of squeezing rollers are positioned after the lubricant supply in the direction of advance of the strip. A pair of squeezing rollers comprises a roller on one side of the rolled strip 2, then a second roller on the other side of the rolled strip 2. The rollers are generally arranged opposite each other so that the force required to bring each squeezing roller of a pair into contact is aligned. Indeed, excessive misalignment of the forces transmitted by each of the rollers could cause undesirable folding of the strip 2.

[0055] The rollers 31, 32 can be mounted to rotate, each having projecting axes, projecting from the two longitudinal ends of the roller, and rotating in bearings, in particular with regard to the embodiment of FIGS. 1 to 10. The diameter of the roller is typically greater than 100 mm such as 150 mm, and in particular in order to limit the deflection of the roller between the two bearings.

[0056] The rollers may be of smaller diameter, for example less than 70mm, in particular with a radius between 26mm and 31.5mm. In such a case, the guidance of the squeezing roller may comprise a set of counter-support rollers Ga, arranged along two axes parallel to the direction of the roller, and coming into contact with the roller along its length, on the side opposite the point of contact between the strip and the squeezing roller, and according to an embodiment illustrated in [Fig.l 1]. The counter-support rollers Ga form supports along two lines of contact with the squeezing roller, holding the squeezing roller along its length.

[0057] In one embodiment, it is possible to provide a single pair 3 of rollers 31, 32, or more pairs 3 of rollers, for example three, four or more pairs of rollers, the rollers being arranged one after the other, each additional stage of pair of rollers being able to improve the overall efficiency of the wringing installation 1.

[0058] In one embodiment, it is possible to provide upstream of the pair of rollers 31, 32 a preliminary barrier device, for example a rubber flap arranged perpendicular to the strip and close to it. Such a preliminary device can in particular make it possible to standardize the height of the layer of lubricant which arrives upstream at the level of the pair of squeezing rollers.

[0059] It is possible according to one embodiment that the rollers are driven in rotation by simple contact with the rolled strip 2, on which the two rollers 31, 32 “roll”.

[0060] Generally speaking, the rollers can thus be mounted freely pivoting, around their axis. During the wringing operations, the friction between the rolled strip and the rollers of the couple causes them to rotate, typically by rolling, in two opposite directions of rotation.

[0061] According to another embodiment, at least one of the two rollers can be driven in rotation by any actuator, such as a motor. In all cases, the rollers each rotate in a direction opposite to the rotation of the other, to accompany the running of the strip 2, namely preferably as much as possible by avoiding or limiting the phenomena of sliding between the rolled strip to be wrung and the wringing rollers.

[0062] According to the present disclosure, in addition to the pair of rollers 31, 32 which performs a first contact wringing operation, the wringing installation 1 is provided with at least one blowing point 41, from which a fluid 4 under pressure is projected. The fluid in question may be, for example, cold or hot, dry air or water vapor. The wringing installation 1 also comprises a guide surface 64 extending downstream from the blowing point 41 towards the upstream following the curvature of the wringing roller 31, 32. The guide surface 64 then forms around the roller a guide channel opening towards the upstream, through which the fluid 4 circulates in the form of a flow of pressurized fluid.

[0063] According to the present disclosure, the pair 3 of rollers performs a first squeezing operation, which may be imperfect, during which a residual layer of lubricant Cr may pass to the downstream side of the pair of rollers, while a blocked layer Cb of lubricant remains on the upstream side, stopped by the pair 3 of rollers. The contact between the rollers and the strip 2 allows this first squeezing operation. Since the contact between the rollers and the strip may be imperfect over a portion of the width of the strip, it is possible for a residual layer to pass this first squeezing operation. Such a residual layer may appear when the profiles of the rollers do not perfectly match the profile of the rolled strip to be squeezing on both sides of the strip, typically leaving, in certain places, gaps between the strip and the rollers, causing lubricant leaks from the upstream side to the downstream side.

[0064] According to one embodiment, at least one or each roller allows a residual layer of lubricant Cr to pass from a blocked layer Cb of lubricant and this on each side of the rolled strip 2, for example above and below the strip 2.

[0065] According to the present disclosure, the pressurized fluid 4 is then projected so as to detach at least a part of the residual layer of lubricant Cr to project a part of it onto the cylindrical surface S of the roller 31, 32 and a part in suspension in the guide channel 66. According to the present disclosure, the surface S on which is projected a part of the residual layer of lubricant is then the same surface which carries out the first wringing operation by contact with the strip 2. According to one embodiment, when the roller is not motorized, the surface S is then the surface on which the roller “rolls” on the strip.

[0066] According to the present disclosure, at least a portion of the residual layer of lubricant Cr adheres to the surface S of the roller. Such adhesion may for example be obtained by capillarity, or by exploiting the surface tension which constitutes a natural property of the lubricant or by any method using any natural or artificial molecular interactions. The adhesion may be obtained or increased for example by a surface treatment of the surface S of the cylinder or by using a coating or an additive in the material of the roller and / or in the lubricant.

[0067] According to the present disclosure, at least a portion of the residual layer of lubricant Cr remains suspended in the flow of pressurized fluid passing through the guide channel 66.

[0068] According to one embodiment, the wringing installation 1 comprises a continuous blowing point 41 over the entire length of the rollers 31, 32.

[0069] According to one embodiment, the wringing installation 1 comprises a plurality of blowing points 41, each of the blowing points 41 projecting lubricant into the guide channel between the roller 31, 32 and the guide surface 64 and onto a surface S of each roller 31, 32 of the at least one pair 3 of rollers, and this on each side of the rolled strip, for example, above the strip and below the rolled strip, so as to also carry out a wringing operation on the other side of the strip which may also comprise a layer of lubricant.

[0070] Generally speaking, each roller 31, 32 which receives a projection of lubricant by the blowing point 41 then brings the residual layer of lubricant back to the upstream side of the pair of rollers by two simultaneous phenomena: - The blowing point creates a flow of fluid around the roller in a guide channel 66 between its cylindrical surface S and the guide surface 64, this flow of fluid bringing back a part of the residual layer of lubricant Cr on the upstream side in the form of droplets suspended in said flow of fluid, - and by rotation of the surface S of the roller on which adheres a part of the residual layer of lubricant Cr, from the downstream side to the upstream side of the pair of rollers, to deposit at least a part on the blocked layer Cb.

[0071] In synergy with the blowing of a pressurized fluid, the rotation of the roller therefore performs both a first wiping operation by contact with the strip 2, and an operation of displacement of a residual quantity of lubricant Cr, which has passed the roller, again on the upstream side of the wiping roller.

[0072] The blocked layer Cb therefore increases in volume as the strip 2 advances and the rollers 31, 32 bring back the residual layer Cr of lubricant to the upstream side. This accumulation of lubricant on the upstream side of the roller, i.e. the blocked layer Cb, must therefore be evacuated laterally.

[0073] Generally speaking, such a spinning process, using in synergy: - on the one hand, blowing a fluid to detach the residual layer of lubricant from the rolled strip and create a flow of fluid around the roller in a guide channel 66 formed between its surface S and the guide surface 64, and thus project the residual layer into the guide channel 66, a part of the residual layer then adhering to the cylindrical surface S of the squeezing roller, another part of the residual layer remaining in suspension in the flow of fluid passing through the guide channel 66, - and on the other hand, the rotation of the roller to bring back the projected lubricant layer adhering to the roller on the upstream side, and the circulation of the fluid flow around the roller 31, 32 in the guide channel 66 to bring the part of the residual layer in suspension in the fluid flow on the upstream side of the pair of rollers. Such synergy makes it possible to obtain efficient wringing of the rolled strip, while limiting the energy requirements (in terms of fluid pressure and flow rate) for blowing.

[0074] It is notably estimated that the use of such a wringing process can allow an improvement in the quantity of wrung lubricant of approximately 50%, and as shown in the graph of [Fig. 12], the upper curve represents the thickness of the residual oil layer from the contact point for a wringing roller without blowing, and the lower curve represents the thickness of the layer with blowing and return of oil from downstream to upstream. In addition, it is possible thanks to such a process to bring the blowing point much closer to the rolled strip, so that the distance between the strip and the blowing point measured perpendicular to the strip is of the order of a millimeter, for example between 1 and 10 mm.

[0075] The distance between the contact point and the blowing point, depending on the direction of travel of the strip, can be between 20 mm and 70 mm, and for example 32 mm for small diameter squeezing rollers such as 63 mm ([Fig.l 1]), or 47 mm for large diameter squeezing rollers such as 150 mm. This makes it possible to considerably reduce the energy required for blowing as well as the noise level generated. The fluid can in particular be projected onto the strip at speeds between 100 and 300 m / s measured at the blowing point, in particular the outlet of a slot 5 defined below.

[0076] The blowing fluid may typically be compressed air.

[0077] The blowing is typically in the form of at least one blade of blowing fluid, notably defined below, which is oriented at an angle of between 30° and 60° by relative to the plane of the moving strip, the blade directed against the current of the moving strip, and so as to push the oil from downstream to upstream, towards the squeezing roller.

[0078] Due to the short distance of the blowing relative to the strip, it is easy to understand that the energy expenditure linked to the blowing is advantageously limited, as well as the noise linked to the blowing, compared to the known solutions of the state of the art presented in the introduction based on evacuation of the residual layer by blowing essentially, or even solely, and which, being located further from the strip, require a significant energy expenditure and are the source of noise.

[0079] Due to the lower blowing implemented compared to the aforementioned state of the art and the presence of the continuous blowing box along the length of the roller and as close as possible to the strip and the roller, the projections of lubricant are greatly limited at the level of said wringing installation, which is particularly advantageous with regard to maintaining the cleanliness of the wringing installation, but also with regard to the quality of the ambient air for the operators nearby.

[0080] According to one embodiment, the blocked layer of lubricant is evacuated by gravity by falling beyond the lateral edges 21, 22 of the strip 2. Indeed, the blocked layer spreads naturally along the roller towards its lateral sides by gravity, and ends up falling from the lateral edges of the strip 2.

[0081] In one embodiment, the rollers 31, 32 of the at least one pair of squeezing rollers cover at least the entire width of the strip 2, so as to force the evacuation of the blocked layer Cd via the lateral edges of the strip 2. According to one embodiment, the squeezing rollers 31, 32 protrude from the lateral edges 21, 22 of the rolled strip.

[0082] According to one embodiment, the fluid 4 is projected in the form of a fluid blade 42, for example an air blade, or air knife. Such a fluid blade can then be continuous over at least the entire length of the strip 2.

[0083] According to one embodiment, the fluid blade extends over the entire length of the squeezing roller(s) onto which the residual layer Cr of lubricant is sprayed. In an embodiment where the squeezing rollers 31, 32 protrude from the strip 2, the fluid blade 42 may also protrude from the strip 2 to prevent lubricant from passing into the space 33 left free between the two rollers 31, 32 of the squeezing pair, beyond the lateral edges 21, 22 of the strip 2.

[0084] The fluid blade can be obtained by making a slot 5 in a hollow box 6 into which the fluid 4 is conveyed under pressure. The blowing point 41 is then the distal end of the slot 5, or the last point at which the fluid 4 is in contact with the box 6 before leaving it.

[0085] According to an embodiment shown [Fig.6], the fluid blade 42 is obtained by creating a clearance between two parts 61, 62 which are assembled together to form the box 6. Such a clearance defines a slot 5 and is obtained by dimensioning the parts so that the clearance is obtained naturally during their assembly. The slot 5 is therefore preferably not obtained by removing material and does not involve a specific manufacturing operation.

[0086] According to one embodiment, such a box 6 is mounted movably on the wringing installation 1 so as to be movable, for example to position the blowing point 41 optimally close to the strip 2 and the wringing roller 31, 32.

[0087] The two parts 61, 62 can be assembled together by screws, as is the case in the embodiment of [Fig. 6]. They can also be assembled by any other means known to those skilled in the art, for example by welding, gluing, or by a mechanical locking means.

[0088] When it is appropriate to obtain a continuous fluid blade 42 over at least the entire length of the strip 2, or even at least the entire length of the squeezing roller 31, 32, the slot 5 can be produced over the desired length. Thus, in one embodiment, the box 6 extends at least over the length of the rollers 31, 32, and the slot is obtained over almost the entire length of the box 6, the lateral edges of the box remaining solid to close the box 6.

[0089] According to one embodiment, the box 6 is produced by assembling at least two parts 61, 62 and forms a volume, opening through the slot 5, supplied with fluid 4 and pressurized by a pressure source.

[0090] Such a volume may in particular be a plenum chamber 63, in which the pressure can be homogenized to facilitate the projection of the fluid 4 through the slot 5, with uniform pressure along the length of the roller.

[0091] The pressure source may for example be a compressor for pressurizing the fluid 4. The pressure source may be any other means known to those skilled in the art for pressurizing a fluid. The pressure source is connected by a fluid circuit 8 to the volume formed by the box 6. The pressure source may be fixedly mounted on the wringing installation 1.

[0092] In an embodiment shown [Fig.7] and 8, the plenum chamber 63 is formed by the two parts 61, 62 which each have a hollow part. The two parts 61, 62 once assembled form both the slot 5, and the plenum chamber 63. The plenum chamber 63 extends over almost the entire length of the box 6, the lateral ends of the box 6 remaining solid to close the plenum chamber 63.

[0093] The blowing point 41 from which the fluid 4 is projected must be located close to the cylinder on which it is configured to project the residual layer of Cr lubricant. Such a configuration makes it possible to reduce the pressure required to detach the lubricant layer and therefore, in particular, to reduce the noise generated by the blowing of the fluid 4.

[0094] Generally speaking, the blowing point 41 must be sufficiently close to the strip 2, and sufficiently close to the cylinder 31, 32 for an optimal result.

[0095] According to an embodiment shown [Fig.9], the squeezing roller 31, 32 is a cylinder with a radius R typically greater than 100 mm such as 150, and the blowing point 41 is positioned in a downstream zone located between the squeezing roller 31, 32 and the rolled strip 2. Such a zone extends downstream of the squeezing roller 31, 32 over at least the entire width of the rolled strip 2 by a length equal to the radius R from the point of contact P between the squeezing roller 31, 32 and the rolled strip 2. This zone is to be redefined in the same way near each cylinder on which a blowing point 41 is configured to project the residual layer of lubricant Cr.

[0096] Such a zone forms a concavity delimited by the surface S of the squeezing roller and the strip. The blowing point 41 is therefore chosen in the immediate vicinity not only of the strip zone on which the residual layer is detached by projection of the fluid, but also of the surface S of the roller on which the detached residual layer of lubricant adheres, namely typically at a dimension smaller than the radius R.

[0097] Arranging the blowing point 41 in the immediate vicinity of the lubricant detachment zone on the rolled strip and of the surface S on which the lubricant projected by the fluid adheres, further advantageously makes it possible to limit, as much as possible, the blowing power required to ensure wringing of the strip, and further contributes to reducing noise. Generally speaking, the blowing point 41 may be at a distance of between 1 mm and 10 mm in a direction perpendicular to the strip, and at a distance from the contact point P between the strip and the wringing roller of between 20 mm and 70 mm in the running direction of the strip.

[0098] For spin rollers of smaller diameter, less than 50mm, the distance between the contact point and the blowing point 71 may however be greater than the radius, and as illustrated in [Fig.l 1].

[0099] In one embodiment, a second blowing point 41 is arranged by pair of wringing rollers on the second roller 32 in a symmetrical manner to that of the first roller 31, relative to the plane defined by the strip 2.

[0100] In one embodiment, it is provided that the guide surface 64 around the squeezing roller, provided at a distance from the latter, has the function of confining the lubricant brought upstream by the roller and in particular to prevent projections by centrifugation when the rollers rotate at high speed.

[0101] According to an embodiment shown [Fig.6], the guide surface 64 is obtained by an external shape of the box 6.

[0102] According to a particular embodiment, the guide surface 64 is obtained by an external shape of one of the two parts 61, 62 of the box 6.

[0103] The blowing point 41 can be removably mounted on the wringing installation 1. This can in particular facilitate the carrying out of maintenance operations on the wringing installation 1. The blowing point can for example be mounted on the wringing installation by removable fixing means known to those skilled in the art.

[0104] In an embodiment shown in [Fig. 10], the installation may comprise a cassette 60 movable in translation along a sliding connection 70 in a direction parallel to the length of the squeezing rollers 31, 32. The blowing point is arranged on the cassette 60 which can then be easily removed from the installation. The cassette typically carries one of the squeezing rollers which is articulated on the bearings which are carried on the cassette.

[0105] The sliding connection 70 can be obtained by complementarity of shapes, between a profiled shape arranged on the cassette 60 and a counter-shape arranged on the wringing installation 1, the shape and the counter-shape being configured to cooperate and allow translation, for example in the direction of elongation of the cassette 60. For example, the complementarity of shape can be dovetail, or T-shaped, or obtained by an intermediate part on one of the cassette 60 or the wringing installation 1.

[0106] The sliding connection 70 can also be obtained by rolling, carried out by any rolling means arranged on one or the other of the cassette 60 or the wringing installation 1, the other being able for example to have a rolling surface on which the rolling means can be movable in translation.

[0107] In an embodiment shown in [Fig. 10], the cassette 60 comprises a roller holder 71, fixed to the cassette 60, for example by a plurality of screws, the roller holder 71 comprising a plurality of rolling rollers 72. The wringing installation comprising a transverse beam 74 fixedly mounted on the installation, on which is arranged a T-shaped groove 73 having at least one rolling surface 75 on which the rolling rollers 72 are configured to rest and roll.

[0108] According to one embodiment, at least one of the transverse beam 74 or the cassette 60 comprises at least one locking means, for example a removable stop surface, to temporarily block the translational movement of the cassette 60 along the T-shaped groove 73, for example so that the cassette does not slide during operation of the wringing installation.

[0109] When the blowing point is formed by a slot arranged in a box 6, the box being for example hollow and connected to a pressurized fluid circuit, the cassette 60 may comprise the box 6 and a removable fixing means for fixing the box 6 to the wringing installation 1.

[0110] In an embodiment in which the blowing point 41 is connected by a pressurized fluid circuit 8 to a pressure source, the fluid circuit 8 may comprise a flexible part configured to accompany a possible movement of the blowing point 41. For example, a translation of the box 6 comprising the blowing point 41 when the latter is mounted movably on the wringing installation 1.

[0111] In a particular embodiment in which the box 6 is formed by the assembly of two parts, the removable fixing means, for example a sliding connection 70, can be arranged on one of the two parts 61, 62.

[0112] In a particular embodiment in which the guide surface 64 is obtained by an external shape of one of the two parts 61, 62 of the box, the guide surface 64 can extend from the blowing point 41 to a fixing zone of the roller holder 71 of the slide connection 70, on the side facing the wringing roller 31, 32.

[0113] In one embodiment, the cassette 60 comprises the box 6 formed by the assembly of the two parts 61, 62, the plenum 63 as well as a fluid connection 65 to a fluid circuit 8. According to a particular embodiment, such a fluid connection 65 may be a quick coupling comprising a seal configured to allow the cassette 60 to be uncoupled from the fluid circuit 8, for example by a translational movement in a direction parallel to that of the sliding connection which connects the cassette 60 to the wringing installation 1. In this way, the cassette 60 is both uncoupled from the fluid circuit 8 and removed from the wringing installation 1 with the same translational movement.

[0114] A seal used for quick coupling may for example be a lip seal, or an O-ring, or any other sealing means configured to operate in translation. Industrial application

[0115] The present technical solutions can be applied to industrial installations, in particular of the rolling mill type, using lubricant. Generally speaking, the method according to the present disclosure and the installation make it possible to significantly increase the dewatering of the rolled strip, and at a lower energy cost compared to the known solutions of the state of the art using a high-power air jet.

[0116] For this purpose the blowing point can typically be located a short distance from the strip in the direction normal to the strip, in particular between 1mm and 10mm, such as 4mm, and at a short distance from the squeezing roller, for example at a distance between 20mm and 70mm from the point of contact P between the strip and the squeezing roller along the direction of the strip. The speed of the blowing fluid can be between 100m / s and 300m / s (measured at the blowing point). List of reference signs

[0117] - 1: Spin-drying installation - 2: Laminated strip - 3: Pair of spin rollers - 4: Fluid - 5: Slot - 6: Box - 8: Fluid circuit - 10: Rolling mill - 21, 22: Side edges of the band - 31, 32: Spin rollers - 41: Blowing point - 42: Fluid blade - 33: Space between two spin rollers - 60: Cassette - 61, 62: Two pieces of the box - 63: Tranquilization chamber - 64: Guide surface - 65: Fluid connection - 66: Guide channel - 70: Slide connection - 71: Roller holder - 72: Rolling rollers - 73: T-groove - 74: Cross beam - 75: Rolling surface - S: Surface - Cb: Blocked layer of lubricant - Cr: Residual layer of lubricant - V: Direction of advance of the strip - P: Point of contact between the wringer roller and the laminated strip - Zs: Zone - Ga: Counter-support rollers.

Claims

Claims

1. A method of dewatering a laminated strip (2) comprising at least one layer of lubricant, the method comprising: - Advancing said rolled strip (2) between at least one pair (3) of two squeezing rollers (31, 32), from an upstream side to a downstream side, the upstream and downstream sides being delimited by the point of contact of each pair (3) of squeezing rollers (31, 32) on the rolled strip (2), each squeezing roller (31, 32) being rotatable in the direction of advance (V) of the rolled strip (2) and performing a first squeezing operation by contact, allowing a residual layer of lubricant (Cr) to pass on the downstream side and allowing a blocked layer (Cb) to accumulate upstream by said pair (3) of squeezing rollers (31, 32); - Projecting a fluid (4) from at least one blowing point (41) onto the rolled strip (2) so as to detach all or part of said residual layer of lubricant (Cr) located downstream of the at least one pair (3) of squeezing rollers (31, 32) thus forming a flow of pressurized fluid circulating in a guide channel (66) formed between a guide surface (64) extending downstream from the blowing point (41) towards upstream around said squeezing roller (31, 32), bypassing said squeezing roller, and a cylindrical surface (S) of at least one of the squeezing rollers (31, 32), at least a part of said detached residual layer (Cr) remaining in suspension in said flow of fluid and at least a part of said detached residual layer (Cr) adhering to said cylindrical surface (S) of at least one of the wringing rollers (31, 32); - Return of the residual layer of lubricant (Cr) from downstream to upstream, a part of said layer of lubricant being returned by the flow of fluid circulating in said guide channel (66), another part adhering to said cylindrical surface (S) being returned by the rotation of at least one of the squeezing rollers (31, 32), the residual layer being returned to the blocked layer (Cb) upstream of at least one of the squeezing rollers (31, 32).

2. A method of dewatering a rolled strip according to the preceding claim, comprising discharging all or part of the blocked lubricant layer (Cb) beyond the lateral edges (21, 22) of the rolled strip (2) and wherein the length of the dewatering roller (31, 32) is greater than the width of the strip (2), the fluid (4) being projected from the at least one blowing point (41) in the form of at least one continuous fluid blade (42) over at least the entire length of the dewatering roller (31, 32), blowing through a space between the rollers, beyond the width of the strip, the fluid blade being configured to prevent the passage of the blocked lubricant layer (Cb) located upstream of the dewatering rollers (31, 32) towards the downstream by passing through the space (33) between the dewatering rollers (31, 32) which protrude beyond the width of the rolled strip (2).

3. A wringing method according to the preceding claim, in which the at least one continuous fluid blade is obtained by projecting a fluid (4) through at least one slot (5), said slot being formed by a clearance between two parts (61, 62) of an assembly forming a box (6), said slot (5) obtained being continuous over at least the entire length of the wringing roller (31, 32), and the two parts (61, 62), once assembled, forming a plenum chamber (63) supplied by a pressure source and opening onto said slot (5).

4. A dewatering method according to any one of the preceding claims, wherein the blowing point (41) from which the fluid (4) is projected is positioned in a zone (Zs), the zone (Zs) extending downstream of the dewatering roller over at least the entire width of the rolled strip (2), the blowing point (41) being located at a distance from the contact point of between 20mm and 70mm along the direction of the strip.

5. A method according to any one of the preceding claims in combination with claim 2, wherein the at least one blowing fluid blade, which is oriented at an angle of between 30° and 60° relative to the plane of the moving strip, the blade being directed countercurrent to the moving strip, so as to push the oil from downstream to upstream, towards the squeezing roller.

6. A method of dewatering according to any preceding claim in combination with claim 3, wherein the surface guide (64) is obtained by an external shape of one of the two parts (61, 62) of said box.

7. A method according to any preceding claim, wherein the blowing point is positioned at a distance from the strip, in the direction normal to the strip, of between 1mm and 10mm.

8. A wringing method according to any one of the preceding claims, in which the projection of the fluid (4) takes place downstream of the two wringing rollers (31, 32) of the at least one pair (3) of wringing rollers (31, 32), on one side and the other of the laminated strip (2).

9. A wringing installation (1) for a rolled strip (2) comprising at least one layer of lubricant, the wringing installation (1) comprising: - At least one pair (3) of two wringing rollers (31, 32) configured to allow the advance, between the two wringing rollers (31, 32) of each pair (3), of said rolled strip (2) from an upstream side to a downstream side, each wringing roller (31, 32) being rotatable in the direction of advance (V) of the rolled strip and being configured to perform a first wringing operation by contact, the upstream and downstream sides being separated by the point of contact of the at least one pair (3) of wringing rollers (31, 32) on the rolled strip (2), each pair (3) of wringing rollers (31, 32) being configured to allow a layer of lubricant to pass through on the downstream side residual lubricant (Cr) and allowing a blocked layer (Cb) to accumulate upstream by said pair of squeezing rollers (31, 32);- At least one blowing point (41) from which a fluid (4) is projected, configured to detach all or part of said residual layer of lubricant (Cr) located downstream of the at least one pair of squeezing rollers (31, 32), the squeezing installation (1) comprising a guide surface (64) extending from downstream from the blowing point (41) towards upstream around said squeezing roller (31, 32), bypassing said squeezing roller, each roller comprising a cylindrical surface (S), a guide channel (66) being formed between said guide surface (64) and said cylindrical surface (S), the projected fluid (4) circulating in a; fluid flow in the guide channel (66), at least a portion of said detached residual layer (Cr) of lubricant remaining suspended in said fluid flow and at least a portion of said detached residual layer of lubricant (Cr) adhering to said cylindrical surface (S) of at least one of the squeezing rollers (31, 32); - a portion of said lubricant layer being returned to the upstream side by the fluid flow circulating in said guide channel (66), another portion adhering to said cylindrical surface (S) being returned by the rotation of at least one of the squeezing rollers (31, 32), all or part of said detached residual layer of lubricant (Cr) then accumulating on the upstream side on the blocked layer (Cb).

10. A wringing installation according to the preceding claim, wherein at least one of the wringing rollers (31, 32) extends over at least the entire width of said rolled strip (2), said wringing rollers (31, 32) being configured to at least partially evacuate the blocked layer (Cb) via the lateral edges (21, 22) of the rolled strip (2) and wherein the length of the wringing roller is greater than the width of the rolled strip (2) and the fluid (4) is projected in the form of a continuous fluid blade over at least the entire length of the wringing roller (31, 32), so as to prevent the passage of the blocked layer of lubricant (Cb) located upstream of the wringing rollers towards the downstream side by passing through the space (33) between the two wringing rollers (31, 32) of a pair (3) which protrude of the width of the rolled strip (2).

11. A wringing installation according to the preceding claim, in which the continuous fluid blade is obtained by projecting a fluid (4) through a slot, said slot being formed by a clearance between two parts (61, 62) of an assembly forming a box (6), said slot obtained being continuous over at least the entire length of said wringing roller, and the two parts (61, 62), once assembled, forming a plenum chamber (63) supplied by a pressure source and opening onto said slot.

12. A wringing installation according to one of claims 9 to 11, the blowing point (41) from which the fluid (4) is projected being positioned in a zone (Zs), the zone (Zs) extending downstream of the roller wringing over at least the entire width of the rolled strip (2), the blowing point (41) being located at a distance from the contact point (P) of between 20mm and 70mm depending on the direction of the strip.

13. Spin-drying installation according to one of claims 9 to 12 in combination with claim 11, in which the guide surface (64) is obtained by an external shape of one of the two parts (61, 62) of said box (6).

14. A wringing installation according to any one of claims 9 to 13, in which the projection of the fluid (4) takes place downstream of the two wringing rollers (31, 32) of the at least one pair (3) of wringing rollers (31, 32), on one side and the other of the laminated strip (2).

15. A wringing installation according to any one of claims 9 to 14, the installation comprising a transverse beam and a cassette (60), removable from the transverse beam, in translation along a sliding connection (70) between the cassette and the transverse beam in a direction parallel to the length of the wringing rollers (31, 32), said cassette (60) comprising one of the wringing rollers and said blowing point (41).

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