Wiping method and wiping device for rolled strip

Abstract

The invention relates to a method for wiping a rolled strip (2), comprising:-moving the rolled strip (2) forward between at least one pair (3) of two wiping rollers (31, 32), performing a first wiping operation, passing a residual lubricant layer (Cr) and accumulating a barrier layer (Cb); spraying a fluid (4) from at least one blow point (41) onto the strip (2) in order to spray a portion of said residual lubricant layer (Cr) into the guide channel (66) between the wiping roller (31, 32) and the blow cartridge (64) and to abut another portion against at least one wiping roller (31, 32) such that it adheres to the surface (S) of said wiping roller (31, 32); and feeding back the lubricant via the guide channel (66) and by rotation of the wiping rollers (31, 32), the lubricant thus falling onto the barrier layer (Cb). The invention also relates to a wiping device implementing such a method.

Description

Technical Field

[0001] The present invention relates to industrial equipment using lubricants, in particular industrial equipment of the rolling mill type. Background Art

[0002] A rolling mill is an industrial machine that allows to carry out a rolling operation, a method of manufacturing through plastic deformation of a strip material, in particular metal. A strip, usually of small thickness relative to its length and width, is driven in translation and compressed between at least two rollers located on either side of the strip thickness. Through this operation, the thickness of the strip is reduced, but also standardized over the entire length of the strip.

[0003] This operation can be carried out at very high speeds, which can involve very fast linear speeds of the strip movement. The stresses in the movement and the considerable speeds require the use of large amounts of lubricant. For example, a possible lubricant flow rate for this application can be about 1000 L / min. Reference is made to "lubricant", but it should be understood that this term refers to a liquid that can perform both lubrication and cooling functions.

[0004] There are two different types of wipers used in these mills:

[0005] - The first type "with large rollers" (meaning with large diameter), extremely rigid over their length, which by its very nature does not allow to obtain perfect contact over the entire width of the roller, and therefore enables a non-negligible metering of lubricant to pass. This drawback requires the use of a blower, but the sprayed lubricant is sprayed in an uncontrolled way and the noise generated is considerable. However, such a solution is very robust, easy to implement and not very costly.

[0006] - The second type "with small rollers", which are relatively flexible and able to deform slightly through several counter-rollers, exerting stress on the counter-rollers through the cylinders so that the small rollers are in perfect contact over the entire width of the strip, which can better block the lubricant. However, such a solution is obviously more complex: it involves the control of several actuators and has high maintenance costs due to the rapid wear of the counter-rollers caused by the small metal particles loaded in the lubricant. This second type of wiper has the disadvantage of being flooded quickly, that is, if the lubricant is used without large roller wipers upstream, the lubricant can reach a level that exceeds the height of the small rollers, because the counter-rolls quickly transfer the lubricant downstream or cause the lubricant to form drops that fall on the strip.

[0007] The present disclosure aims to improve upon these two types of wipers by providing solutions that address all or part of the disadvantages of these two types of wipers. Summary of the invention

[0008] According to a first aspect of the present disclosure, a method for wiping a rolled strip comprising at least one lubricant layer is proposed, the method comprising:

[0009] - the rolled strip moves forward from the upstream side toward the downstream side between at least one pair of two wiping rollers, the upstream side and the downstream side being defined by the contact points of each pair of wiping rollers on the rolled strip, each wiping roller rotates and moves along the forward moving direction of the rolled strip, and performs a first wiping operation by contact, so that the residual lubricant layer is transferred to the downstream side, and the blocking layer blocked by the pair of wiping rollers is accumulated upstream;

[0010] - injecting a fluid from at least one blowing point onto the rolled strip in order to strip all or part of said residual lubricant layer located downstream of at least one pair of wiping rollers, thereby forming a pressurized fluid flow circulating in a guide channel formed between a guide surface and a cylindrical surface of at least one wiping roller, the guide surface extending around said wiping roller from downstream of the blowing point to upstream while bypassing said wiping roller, at least part of said stripped residual layer remaining suspended in said fluid flow and at least part of said stripped residual layer adhering to said cylindrical surface of at least one wiping roller;

[0011] - The residual lubricant layer is sent back from downstream to upstream, a part of the lubricant layer is sent back by the fluid flow circulating in the guide channel, another part of the lubricant layer attached to the cylindrical surface is sent back by the rotation of at least one wiping roller, and the residual layer is sent back to the layer blocked upstream of at least one wiping roller.

[0012] The features disclosed in the following paragraphs may be selectively implemented independently of each other or in combination with each other:

[0013] The method may include withdrawing all or part of the barrier layer of lubricant beyond the lateral edges of the rolled strip.

[0014] The length of the wiping roller can be greater than the width of the strip, and the fluid is sprayed from at least one blowing point to at least the entire length of the wiping roller in the form of at least one continuous fluid blade, blowing through the space between the rollers and exceeding the width of the strip. The fluid blade is configured to prevent a barrier layer of lubricant located upstream of the wiping roller from passing downstream by passing through the space between the wiping rollers, and the space extends beyond the width of the rolled strip.

[0015] At least one continuous fluid blade may be obtained by ejecting the fluid through at least one slot formed by a gap between two parts of the assembly forming the box, the slot being continuous at least over the entire length of the wiping roller and the two parts, once assembled, forming a pressurization chamber supplied by a pressure source and opening into the slot.

[0016] Preferably, the blowing point of the jet of fluid is located in a region extending downstream of the wiping roller over at least the entire width of the rolled strip, the blowing point being between 20 mm and 70 mm in the direction of the strip from the contact point between roller and strip.

[0017] In other words, the blowing point can be located in an area which extends downstream of the wiping roller over at least the entire width of the rolled strip and over a length of 70 mm in the direction of the strip, the blowing point being positioned at least 20 mm from the contact point between the roller and the strip along the direction of the strip.

[0018] According to one possibility, the wiping roller can be a cylinder with a certain radius, in particular with a diameter greater than 100 mm (for example 150 mm), and the blowing point of the spray fluid can be located in a recessed area between the wiping roller and the rolled strip, which extends downstream of the wiping roller over at least the entire width of the rolled strip and whose length is equal to the radius of the contact point between the wiping roller and the rolled strip.

[0019] According to a second possibility, in particular for rollers with smaller diameters (for example between 52 mm and 63 mm) or with radii of 26 mm and 31.5 mm respectively, the distance between the blowing point and the contact point can therefore be greater than the radius, for example equal to 32 mm.

[0020] In general, the distance between the blowing point and the contact point, measured in the direction of movement of the strip, may therefore be between 20 mm and 70 mm, for example 47 mm.

[0021] At least one blowing fluid blade, which may be oriented at an angle between 30° and 60° relative to the plane of the moving strip, is directed countercurrently relative to the moving strip so as to return lubricant from downstream to upstream, towards the wiping roller.

[0022] The guiding surface may be obtained by the outer shape of one of the two parts of the box.

[0023] The injection of the fluid may be performed downstream of both wiping rollers of at least one pair of wiping rollers, on either side of the rolled strip.

[0024] According to the normal direction of the strip, the distance between the blowing point and the strip is between 1 mm and 10 mm, for example, 4 mm.

[0025] According to a second aspect of the present disclosure, a device for wiping a rolled strip comprising at least one lubricant layer is proposed, the wiping device comprising:

[0026] - at least one pair of two wiping rollers, which are configured to allow the rolled strip to move forward from the upstream side toward the downstream side between the two wiping rollers of each pair, each wiping roller is rotationally moved along the forward moving direction of the rolled strip and is configured to perform a first wiping operation by contact, the upstream side and the downstream side being separated by the contact points of the at least one pair of wiping rollers on the rolled strip, each pair of wiping rollers being configured to transfer a residual lubricant layer to the downstream side and to accumulate a blocking layer blocked by the pair of wiping rollers toward the upstream;

[0027] - at least one blowing point from which a fluid is ejected, which is configured to strip all or part of the residual lubricant layer located downstream of the at least one pair of wiping rollers, the wiping device comprising a guide surface extending from downstream of the blowing point to upstream around the wiping rollers while bypassing the wiping rollers, each roller comprising a cylindrical surface, a guide channel being formed between the guide surface and the cylindrical surface, the ejected fluid circulates in the fluid flow in the guide channel, at least part of the stripped residual layer remains suspended in the fluid flow, and at least part of the stripped residual lubricant layer adheres to the cylindrical surface S of at least one wiping roller;

[0028] -A portion of the lubricant layer is sent back to the upstream side by the fluid flow circulating in the guide channel, and another portion of the lubricant layer attached to the cylindrical surface is sent back by the rotation of at least one wiping roller, thereby all or part of the peeled residual lubricant layer accumulates on the upstream side of the barrier layer.

[0029] Generally speaking, the device may be configured to implement the method according to the present disclosure.

[0030] The features disclosed in the following paragraphs may be selectively implemented independently of each other or in combination with each other:

[0031] At least one of the wiping rollers may extend over at least the entire width of the rolled strip, the wiping roller being configured to at least partially withdraw the barrier layer from a lateral edge of the rolled strip.

[0032] The length of the wiping roller can be greater than the width of the rolled strip, and the fluid can be sprayed in the form of a continuous fluid blade onto at least the entire length of the wiping roller, thereby preventing a barrier layer of lubricant located upstream of the wiping roller from passing through the space between a pair of two wiping rollers and passing downstream, which space extends beyond the width of the rolled strip.

[0033] The continuous fluid blade can be obtained by ejecting a fluid through a slot formed by a gap between two parts of the assembly forming the box, the slot being continuous at least over the entire length of the wiping roller and the two parts once assembled forming a booster chamber supplied by a pressure source and which opens into the slot.

[0034] The wiping roller is a cylinder with a certain radius, and the blowing point of the spray fluid is located in a concave area between the wiping roller and the rolled strip. The concave area extends downstream of the wiping roller over at least the entire width of the strip, and its length is equal to the radius of the contact point between the wiping roller and the rolled strip.

[0035] The guiding surface may be obtained by the outer shape of one of the two parts of the box.

[0036] The injection of the fluid is carried out downstream of both wiping rollers of at least one pair of wiping rollers, on either side of the rolled strip.

[0037] The device may comprise a crossbeam and a cassette detachable from the crossbeam, the cassette translating along a sliding link between the cassette and the crossbeam in a direction parallel to the length of the wiping rollers, the cassette comprising one of the wiping rollers and the blowing point.

[0038] The cassette comprises the box which may be formed by assembly of two parts, a pumping chamber and fluid connections to a fluid circuit.

[0039] The fluid connection is a quick release coupling including a sealing joint that allows the cassette to be decoupled from the fluid circuit by translation according to the direction of the sliding link.

[0040] The sliding link is obtained by cooperation between a roller holder fastened to a cassette comprising a plurality of rollers and a groove in the form of a T-slot arranged in a fixed crossbeam having at least one rolling surface configured to guide the translation of the plurality of rollers. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Other features, details and advantages will become apparent upon reading the following detailed description and analyzing the accompanying drawings, in which:

[0042] Figure 1

[0043] [ Figure 1 ] shows an overall view of a rolling mill provided with a wiper according to one embodiment.

[0044] Figure 2

[0045] [ Figure 2] shows a detailed view of a wiper according to an embodiment, in particular showing two wiping rollers, which have a large diameter (greater than 100 mm), for example 150 mm, which are hinged at their ends.

[0046] Figure 3

[0047] [ Figure 3 ] shows a detailed view of a wiping method according to one embodiment.

[0048] Figure 4 and Figure 5

[0049] [ Figure 4 ]and[ Figure 5 ] shows a cartridge according to one embodiment.

[0050] Figure 6

[0051] [ Figure 6 ] shows a detailed view of a wipe box according to one embodiment.

[0052] Figure 7 and Figure 8

[0053] [ Figure 7 ]and[ Figure 8 ] Two components of a wiper box according to one embodiment are shown in detail.

[0054] Fig. 9

[0055] [ Fig. 9 ] shows a detailed view of the box of a wiper according to one embodiment, in particular showing the distance between the blowing point and the point of contact with the strip along the direction of movement of the strip, which for rollers with large diameters is typically smaller than the diameter of the wiping roller.

[0056] Fig.10

[0057] [ Fig.10 ] shows in detail the two parts of a wiper box according to one embodiment, and a sliding link that allows the box to be pulled out or inserted into the crossbeam, wherein the sliding link includes a groove in the shape of a T and a set of rollers rolling on the track of the groove.

[0058] Fig.11

[0059] [ Fig.11] is a cross-sectional view of a second embodiment, in which the wiping roller has a smaller diameter, typically having a radius less than 50 mm, for example between 26 mm and 31.5 mm, the blowing point is located at a distance from the contact point between the wiping roller and the strip that is greater than the radius of the roller, and a plurality of rollers are distributed against the wiping roller on the side opposite to the contact point with the strip.

[0060] Fig.12

[0061] [ Fig.12 ] is a graph in which the ordinate represents the thickness of the lubricant layer and the abscissa represents the distance from the downstream area to the contact point, which shows:

[0062] - the amount of lubricant remaining in the downstream zone of the strip, starting from the point of contact with the wiping roller of a wiping device according to the prior art, without blowing, according to a first curve (at the top, marked by a cross),

[0063] - According to a second curve (at the bottom, indicated by a circle), the amount of lubricant remaining in the downstream zone of the strip, starting from the point of contact with the wiping roller of a wiping device according to the disclosure, provided with an air blow according to the disclosure and with guide surfaces ensuring the return of the lubricant. DETAILED DESCRIPTION

[0064] Reference now Figure 1 The left part of the figure shows a rolling mill 10. The two smallest rolls are the "working" rolls, which are used to transfer compressive stresses to the strip to reduce the strip thickness and standardize its thickness. The function of the other "intermediate" rolls is to avoid deformation of the working rolls and to transfer compressive stresses to the working rolls.

[0065] The invention is suitable for wiping a strip rolled by a rolling mill, which can be, for example, a rolling mill with 2, 4, 6 or up to 20 drums, such as Figure 1 As shown, including:

[0066] - a lower working cylinder and an upper working cylinder located on either side of the rolled strip,

[0067] - two first lower intermediate cylinders, each in contact with the lower working cylinder, and two upper intermediate cylinders,

[0068] Contact with the upper working cylinder respectively,

[0069] - three second lower intermediate cylinders, each in contact with two first lower intermediate cylinders in pairs, and three second upper intermediate cylinders, each in contact with two first upper intermediate cylinders in pairs,

[0070] - Four sets of lower bearing rollers in contact with the three second lower intermediate cylinders in pairs, and four sets of upper bearing rollers in contact with the three second upper intermediate cylinders in pairs.

[0071] The set of bearing rollers is usually mounted with an eccentric system, which allows to ensure the clamping of the strip, or even to ensure the control of the bending of the cylinders, including that of the working cylinder.

[0072] By controlling the bending, a strip profile can be imparted to the rolled strip, which profile can be straight or, more generally, curved.

[0073] This type of mill usually includes four rods that spray lubricant, usually a mixture of oil and water, onto the working cylinder. Figure 1 In the embodiment shown, two bars are arranged in the upper part on one side of the rolled strip 2 and two bars are arranged in the lower part on the other side of the rolled strip 2. Each bar comprises along its length, transversely to the strip, a series of nozzles which ensure that the lubricant is sprayed over the width of the strip and / or onto the rollers of the rolling mill.

[0074] The embodiments of the wiping device 1 disclosed in this document are not limited to only Figure 1 The use shown is in a rolling mill with 20 drums, which is shown only as an example and can be applied to any industrial equipment of the type of strip rolling mill using lubricants.

[0075] The embodiments of the wiping device 1 disclosed in this document are not limited to only the presence of Figure 1 While shown for use with a "large roller" wiper, this is shown by way of example only and may be applicable to any wiper device using a roller.

[0076] According to one embodiment, the strip 2 first passes through the rolling mill 10 and then passes through the wiping device 1 from the upstream side (from the rolling mill) towards the downstream side (after each pair of rollers 3 of the wiping device), which wiping device 1 defines the forward movement direction V of the rolled strip 2.

[0077] By way of non-limiting example Figure 1 In the illustrated embodiment, the wiping device shown comprises two pairs of rollers 3, which are arranged successively in stages to improve the wiping effect.

[0078] The wiping roller can be cylindrical. For both rollers of the wiping pair, the rollers can also have a non-cylindrical profile, in particular a convex and / or concave profile. The wiping roller profile is selected to conform as closely as possible to the profile of the strip being rolled in the rolling mill. This profile adaptability improves the wiping efficiency of the rollers by limiting the gap and facilitating the passage of the residual lubricant layer.

[0079] Generally speaking, one or more pairs of wiping rollers are positioned after the location where the lubricant is provided, according to the forward movement direction of the strip. The wiper pair comprises a roller on one side of the rolled strip 2 and then a second roller on the other side of the rolled strip 2. These rollers are usually arranged facing each other, the placement being such that the stresses required for contact of each wiping roller in a pair of wiping rollers are aligned. In fact, too much misalignment of the stresses transmitted by each roller could lead to undesired bending of the strip 2.

[0080] The rollers 31, 32 may be rotatably mounted, each having a projecting axis protruding from both longitudinal ends of the roller, and rotating in bearings, in particular for Figures 1 to 10 The diameter of the roller is usually greater than 100 mm, for example 150 mm, and is particularly intended to limit bending of the roller between the two bearings.

[0081] The roller may have a smaller diameter, for example less than 70 mm, in particular with a radius between 26 mm and 31.5 mm. In this case, the guidance of the wiping roller may comprise a set of counter-bearing rollers Ga arranged according to two axes parallel to the direction of the roller and according to Fig.11 The embodiment shown, on the opposite side of the contact point between the strip and the wiping roller, is in contact with the roller over its length. The counter-bearing roller Ga forms a support along the two contact lines with the wiping roller, thus holding the wiping roller over its length.

[0082] In one embodiment, a single pair of 3 rollers 31, 32 may be provided, or multiple pairs of 3 rollers, such as three, four or more pairs of rollers, arranged one after the other, each additional stage of a pair of rollers being able to improve the overall efficiency of the wiping device 1.

[0083] In one embodiment, a primary barrier device, such as a rubber flap arranged perpendicular to and close to the strip, may be provided upstream of the pair of rollers 31, 32. Such a primary device may allow in particular a high standardization of the lubricant layer reaching upstream of the pair of wiping rollers.

[0084] According to one embodiment, the rollers can be driven in rotation by simple contact with the rolled strip 2 , on which the two rollers 31 , 32 “roll”.

[0085] Generally speaking, the rollers may thus be mounted so as to pivot freely about their axes.During the wiping operation, the friction between the rolled strip and the pair of rollers drives them in rotation, usually by rolling, in two opposite directions of rotation.

[0086] 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, each roller rotates in the opposite direction to the rotation of the other roller to accompany the movement of the strip 2, i.e. preferably, to avoid as much as possible or at the same time limit the slip phenomenon between the rolled strip to be wiped and the wiping roller.

[0087] According to the invention, in addition to the pair of rollers 31, 32 that perform the first wiping operation by contact, the wiping device 1 is provided with at least one blowing point 41 from which a pressurized fluid 4 is ejected. The fluid in question may be, for example, dry cold or hot air or water vapor. The wiping device 1 also comprises a guide surface 64 that extends from downstream to upstream of the blowing point 41, while following the curvature of the wiping rollers 31, 32. The guide surface 64 thus forms a guide channel around the rollers, which is open toward upstream, through which the fluid 4 circulates in the form of a pressurized fluid stream.

[0088] According to the invention, the pair of 3 rollers performs a first wiping operation, which may be imperfect, during which a residual layer of lubricant Cr can pass to the downstream side of the pair of rollers, while a barrier layer of lubricant Cb remains on the upstream side, stopped by the pair of 3 rollers. The contact between the rollers and the strip 2 allows this first wiping operation. Since the contact between the rollers and the strip may be imperfect over a portion of the strip width, a residual layer may pass through this first wiping operation. This residual layer occurs when the profile of the rollers does not perfectly conform to the profile of the rolled strip to be wiped on both sides of the strip, usually leaving gaps between the strip and the rollers at certain locations, causing the lubricant to leak from the upstream side to the downstream side.

[0089] According to one embodiment, on each side of the rolled strip 2 , for example above and below the strip 2 , at least one or each roller allows the residual lubricant layer Cr to pass from the barrier layer Cb of lubricant.

[0090] According to the invention, the pressurized fluid 4 is thus sprayed to strip at least part of the residual lubricant layer Cr, to spray part of the residual lubricant layer onto the cylindrical surface S of the rollers 31, 32 and to suspend part of the residual lubricant layer in the guide channel 66. According to the invention, the surface S onto which part of the residual lubricant layer is sprayed is thus the same surface as that on which the first wiping operation is performed by contact with the strip 2. According to one embodiment, when the rollers are not motorized, the surface S is then the surface on which the rollers “roll” on the strip.

[0091] According to the invention, at least a portion of the residual lubricant layer Cr adheres to the surface S of the roller. This adhesion can be obtained, for example, by capillary action, or by exploiting the surface tension constituting the natural properties of the lubricant, or by any method using any natural or artificial molecular interaction. Adhesion can be obtained or increased, for example, by surface treatment of the surface S of the cylinder or by using coatings or additives in the material of the roller and / or in the lubricant.

[0092] According to the present invention, at least a portion of the remaining lubricant layer Cr remains suspended in the flow of pressurized fluid flowing through the guide channel 66 .

[0093] According to one embodiment, the wiping device 1 comprises a series of blowing points 41 over the entire length of the rollers 31 , 32 .

[0094] According to one embodiment, the wiping device 1 comprises a plurality of blowing points 41, each of which sprays lubricant into the guide channel between the rollers 31, 32 and the guide surface 64 and onto the surface S of each roller 31, 32 of at least one pair 3 of rollers 31, 32, on each side of the rolled strip, for example above the strip and below the rolled strip, so that the wiping operation is also performed on the other side of the strip, which may also include a layer of lubricant.

[0095] In general, therefore, each roller 31, 32 receiving a jet of lubricant through a blowing point 41 brings the residual lubricant layer back to the upstream side of the roller pair by two simultaneous phenomena:

[0096] - the blowing point generates a fluid flow around the roller in the guide channel 66 between the cylindrical surface S of the roller and the guide surface 64, which returns part of the residual lubricant layer Cr to the upstream side in the form of droplets suspended in said fluid flow,

[0097] - And by rotating the surface S of the roller to which a part of the remaining lubricant layer Cr is attached from the downstream side toward the upstream side of the pair of rollers, at least a part of the barrier layer Cb is deposited there.

[0098] In cooperation with the blowing of the pressurized fluid, the rotation of the roller thus simultaneously performs a first wiping operation by contact with the strip 2 and a moving operation of the residual amount of lubricant Cr, which has passed through the roller, back to the upstream side of the wiping roller.

[0099] Therefore, when the strip 2 moves forward and the rollers 31, 32 bring the remaining lubricant layer Cr to the upstream side, the volume of the barrier layer Cb increases. Therefore, the lubricant accumulated on the upstream side of the rollers, ie, the barrier layer Cb, must be withdrawn laterally.

[0100] Generally speaking, such wiping methods are used in conjunction with:

[0101] - on the one hand, blowing fluid to strip the residual lubricant layer from the rolled strip and generating a fluid flow around the roller in a guide channel 66 formed between the surface S of the roller and the guide surface 64, and thus ejecting the residual layer into the guide channel 66, a part of the residual layer thus adhering to the cylindrical surface S of the wiping roller, another part of the residual layer remaining suspended in the fluid flow traveling through the guide channel 66,

[0102] - On the other hand, the rotation of the rollers brings the sprayed lubricant layer adhering to the rollers to the upstream side, and the fluid flow circulates around the rollers 31, 32 in the guide channel 66 to bring part of the residual layer suspended in the fluid flow to the upstream side of the pair of rollers. This synergy allows to obtain an effective wiping of the rolled strip while limiting the energy requirements of the blowing (in terms of fluid pressure and flow rate).

[0103] It is particularly estimated that the use of this wiping method can increase the amount of lubricant wiped by about 50%, such as Fig.12 The upper curve represents the thickness of the remaining lubricant layer starting from the contact point of the wiping roller without air blowing, and the lower curve represents the layer thickness when the lubricant is blown from downstream to upstream. Furthermore, the blowing point can be moved significantly closer to the rolled strip via this method, so that the distance between the strip and the air blow measured perpendicular to the strip is about 1 mm, for example between 1 mm and 10 mm.

[0104] In the direction of movement of the strip, the distance between the contact point and the blowing point can be between 20 mm and 70 mm, for example, for a wiping roller with a small diameter (for example 63 mm), the distance is 32 mm ( Fig.11 ), or for a wiping roller with a large diameter (for example 150 mm), the distance is 47 mm. This makes it possible to significantly reduce the energy required for blowing and the noise level generated. In particular, the fluid can be injected onto the strip at a speed of between 100 m / s and 300 m / s measured at the blowing point, in particular at the outlet of the slot 5 defined below.

[0105] The blowing point can usually be compressed air.

[0106] The air blow is typically in the form of at least one air blow fluid blade, as defined below, oriented at an angle between 30° and 60° relative to the plane of the moving strip, the blade being directed counter-currently relative to the moving strip, thereby pushing the lubricant from downstream back upstream towards the wiping roller.

[0107] Due to the small distance of the blowing relative to the strip, it is easy to understand that both the energy consumption associated with the blowing and the noise associated with the blowing are advantageously limited compared to the solutions known from the prior art, which are based on evacuating the residual layer essentially or even exclusively by blowing and which are at a large distance from the strip, requiring a significant energy consumption, which is the cause of the noise.

[0108] Due to the weaker blowing compared to the aforementioned prior art and the presence of a continuous blow box over the length of the roller and as close as possible to the strip and the roller, the injection of lubricant is greatly limited at the wiping device, which is particularly advantageous for maintaining the cleanliness of the wiping device and also for the ambient air quality of nearby operators.

[0109] According to one embodiment, the barrier layer of lubricant is evacuated by gravity by falling outside the lateral edges 21, 22 of the strip 2. In fact, the barrier layer is naturally spread out by gravity along the roller towards its lateral edges and finally falls from the lateral edges of the strip 2.

[0110] In one embodiment, the rollers 31, 32 of at least one pair of wiping rollers cover at least the entire width of the strip 2, thereby forcing the barrier layer Cb to withdraw through the lateral edges of the strip 2. According to one embodiment, the wiping rollers 31, 32 extend beyond the lateral edges 21, 22 of the rolled strip.

[0111] According to one embodiment, the fluid 4 is injected in the form of a fluid blade 42 , such as a blade of air or an air blade. Such a fluid blade may thus be continuous over at least the entire length of the strip 2 .

[0112] According to one embodiment, the fluid blades extend over the entire length of the wiping rollers, onto which the residual lubricant layer Cr is sprayed. In embodiments where the wiping rollers 31, 32 extend beyond the strip 2, the fluid blades 42 may also extend beyond the strip 2 to prevent the lubricant from entering the free space 33 between the pair of wiping rollers 31, 32 beyond the lateral edges 21, 22 of the strip 2.

[0113] The fluid blade can be obtained by creating a slot 5 in a hollow box 6 into which the fluid 4 is delivered under pressure. Thus, the blowing point 41 is the distal end of the slot 5, or the last point where the fluid 4 contacts the box 6 before leaving it.

[0114] according to Figure 6In the embodiment shown, the fluid blade 42 is obtained by creating a gap between the two parts 61, 62 assembled together to form the box 6. This gap defines the slot 5 and is obtained by determining the dimensions of the parts so that the gap is naturally obtained during the assembly process. Therefore, the slot 5 is preferably not obtained by removing material and does not involve a specific manufacturing operation.

[0115] According to one embodiment, such a box 6 is movably mounted on the wiping device 1 so as to be movable, for example to position the blowing point 41 in the vicinity of the strip 2 and the wiping rollers 31 , 32 in an optimal manner.

[0116] The two components 61, 62 can be assembled together by screws, such as Figure 6 They can also be assembled by any other means known to those skilled in the art, for example by welding, gluing, or by mechanical locking means.

[0117] The slot 5 can be made to the desired length when it is suitable to obtain a continuous fluid blade 42 over at least the entire length of the strip 2, or even over at least the entire length of the wiping rollers 31, 32. 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.

[0118] According to one embodiment, the box 6 is assembled from at least two parts 61 , 62 and forms a volume open through the slot 5 , supplied with the fluid 4 and pressurized by a pressure source.

[0119] Such a volume may in particular be a plenum chamber 63, wherein the pressure may be homogenized to promote the ejection of the fluid 4 through the slot 5, with a uniform pressure over the length of the roller.

[0120] The pressure source may be, for example, a compressor for pressurizing the fluid 4. The pressure source may be any other device known to those skilled in the art for pressurizing a fluid. The pressure source is connected to the volume formed by the box 6 via a fluid circuit 8. The pressure source may be mounted on the wiping device 1 in a fixed manner.

[0121] exist Figure 7 and Figure 8 In the embodiment shown, the plenum chamber 63 is formed by two parts 61, 62, each of which includes a hollow portion. The two parts 61, 62 once assembled form the slot 5 and the plenum chamber 63. The plenum chamber 63 extends almost over the entire length of the box 6, and the side ends of the box 6 remain solid to close the plenum chamber 63.

[0122] The blowing point 41 of the ejecting fluid 4 must be located near the cylinder, the blowing point 41 being configured to eject the residual lubricant layer Cr onto the cylinder. This configuration allows reducing the pressure required to strip the lubricant layer and therefore, in particular, reducing the noise generated by the blowing of the fluid 4.

[0123] Generally speaking, the blowing point 41 must be close enough to the strip 2 and close enough to the cylinders 31, 32 to obtain the best results.

[0124] according to Fig. 9 In the embodiment shown, the wiping rollers 31, 32 are cylinders with a radius R generally greater than 100 mm, for example 150 mm, and the blowing point 41 is located in the downstream zone between the wiping rollers 31, 32 and the rolled strip 2. Such a zone extends downstream of the wiping rollers 31, 32 over at least the entire width of the rolled strip 2, the width being equal to the length of the radius R starting from the contact point P between the wiping rollers 31, 32 and the rolled strip 2. This zone must be redefined in the same way near each cylinder, and the blowing point 41 is configured to spray the residual lubricant layer Cr on each cylinder.

[0125] Such an area forms a recess defined by the surface S of the wiping roller and the strip. Therefore, the blowing point 41 is selected not only in the area immediately adjacent to the strip area from which the residual layer is stripped by the injection of the fluid, but also in the area immediately adjacent to the surface S of the roller on which the stripped residual lubricant layer adheres, i.e., generally smaller in size than the radius R.

[0126] The arrangement of the blowing points 41 in the immediate vicinity of the lubricant stripping area on the rolled strip and the surface S to which the lubricant sprayed by the fluid adheres also allows advantageously limiting the blowing power required to ensure the wiping of the strip as much as possible and also helps to reduce noise. In general, the blowing points 41 can be located at a distance between 1 mm and 10 mm in the direction perpendicular to the strip and at a distance between 20 mm and 70 mm from the contact point P between the strip and the wiping roller in the direction of movement of the strip.

[0127] For a wiping roller with a smaller diameter, less than 50 mm, the distance between the contact point and the blowing point 71 may be greater than the radius, such as Fig.11 shown.

[0128] In one embodiment, relative to the plane defined by the strip 2 , a second blowing point 41 symmetrical to the first roller 31 is provided on each pair of wiping rollers.

[0129] In one embodiment, the surface 64 is intended to be guided around the wiping roller, being arranged at a distance therefrom, to have the function of limiting the lubricant brought back upstream by the roller and in particular to avoid spraying due to centrifugal action when the roller rotates at high speed.

[0130] according to Figure 6 In the embodiment shown, the guide surface 64 is obtained by the external shape of the box 6 .

[0131] According to a particular embodiment, the guide surface 64 is obtained by the external shape of one of the two parts 61 , 62 of the box 6 .

[0132] The blowing point 41 can be detachably mounted on the wiping device 1. This is particularly advantageous for maintenance operations on the wiping device 1. The blowing point can be mounted on the wiping device, for example, by detachable fastening means known to the person skilled in the art.

[0133] exist Fig.10 In the embodiment shown, the device can include a cassette 60 that is movable in translation along a sliding link 70 in a direction parallel to the length of the wiping rollers 31, 32. The blowing points are arranged on the cassette 60 so that it can be easily removed from the device. The cassette usually carries one of the wiping rollers, which is hinged on a bearing on the cassette.

[0134] The sliding link 70 can be obtained by a shape complementarity between a contour shape provided on the cartridge 60 and a reverse shape provided on the wiping device 1, which shape and the reverse shape are configured to cooperate with each other and allow translation, for example, translation according to the elongation direction of the cartridge 60. For example, the shape complementarity can be a dovetail, or a T-shape, or obtained by the shape of an intermediate part on one of the cartridge 60 or the wiping device 1.

[0135] The sliding link 70 may also be obtained by rolling, performed by any rolling means arranged on one or the other of the cartridge 60 or the wiping device 1 , the other being able for example to have a rolling surface on which the rolling means can move in translation.

[0136] exist Fig.10 In the embodiment shown, the cassette 60 comprises a roller holder 71, which is fastened to the cassette 60, for example by a plurality of screws, the roller holder 71 comprising a plurality of rollers 72. The wiping device comprises a crossbar 74 mounted on the device in a fixed manner, on which a T-shaped groove 73 is arranged, the groove having at least one rolling surface 75 on which the rollers 72 are configured to rest and roll.

[0137] According to one embodiment, at least one of the crossbar 74 or the cassette 60 comprises at least one locking device, such as 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 slip during operation of the wiping device.

[0138] When the blowing points are formed by slots arranged in a box 6 , for example hollow and connected to a pressurized fluid circuit, the magazine 60 may comprise the box 6 and removable fastening means for fastening the box 6 to the wiping device 1 .

[0139] In one embodiment in which the blowing point 41 is connected to a pressure source via a pressurized fluid circuit 8, the fluid circuit 8 may comprise a flexible part configured to accompany a possible movement of the blowing point 41. For example, when the box 6 is movably mounted on the wiping device 1, a translation of the box 6 comprises a translation of the blowing point 41.

[0140] In the particular embodiment in which the box 6 is assembled from two parts, the removable fastening means, for example a sliding link 70 , may be arranged on one of the two parts 61 , 62 .

[0141] In the particular embodiment in which the guide surface 64 is obtained by the outer shape of one of the two parts 61 , 62 of the box, the guide surface 64 can extend from the blowing point 41 to the fastening area of ​​the roller holder 71 of the sliding link 70 , on the side facing the wiping rollers 31 , 32 .

[0142] In one embodiment, the cartridge 60 comprises a box 6 assembled from two parts 61, 62, a pumping chamber 63 and a fluid connection 65 connected to the fluid circuit 8. According to a particular embodiment, such a fluid connection 65 may be a quick-release coupler comprising a sealing joint configured to allow the cartridge 60 to be decoupled from the fluid circuit 8, for example, by a translational movement along a direction parallel to a sliding link that connects the cartridge 60 to the wiping device 1. In this way, the cartridge 60 is both decoupled from the fluid circuit 8 and removed from the wiping device 1 by the same translational movement.

[0143] The sealing joint for a quick release coupler may be, for example, a lip seal, or an O-ring, or any other sealing device configured to operate in translation.

[0144] Industrial Applicability

[0145] The technical solution can be applied to industrial equipment using lubricants, in particular industrial equipment of the rolling mill type. In general, the method and the device according to the invention allow to significantly increase the wiping of the rolled strip, with lower energy costs, compared to the solutions known in the prior art using high-power air jets.

[0146] For this purpose, the blowing point can usually be located at a small distance from the normal direction of the strip, in particular at a distance between 1 mm and 10 mm, for example 4 mm, and at a small distance from the wiping roller, for example, depending on the direction of the strip, at a distance between 20 mm and 70 mm from the contact point P between the strip and the wiping roller. The velocity of the blowing fluid can be between 100 m / s and 300 m / s (measured at the blowing point).

[0147] Reference numerals list

[0148] -1: Wipe the device

[0149] -2: Rolled strip

[0150] -3: Wiping roller pair

[0151] -4: Fluid

[0152] -5: Slot

[0153] -6: Box-8: Fluid circuit-10: Rolling mill-21, 22: Lateral strip edges-31, 32: Wiping rollers-41: Blowing point-42: Fluid blades-33: Space between two wiping rollers-60: Cassette-61, 62: Two parts of the box-63: Pressurization chamber-64: Guide surface-65: Fluid connection-66: Guide channel-70: Sliding link-71: Roller holder-72: Roller-73: T-groove-74: Crossbeam-75: Rolling surface-S: Surface-Cb: Lubricant barrier layer-Cr: Residual lubricant layer-V: Direction of forward movement of the strip-P: Contact point between wiping roller and rolled strip-Zs: Area

[0154] -Ga: Counter bearing roller.

Claims

1. A method for wiping a rolled strip (2) comprising at least one lubricant layer, the method comprising: - the rolled strip (2) moves forward from the upstream side toward the downstream side between at least one pair (3) of two wiping rollers (31, 32), the upstream side and the downstream side being defined by the contact points of each pair (3) of wiping rollers (31, 32) on the rolled strip (2), each wiping roller (31, 32) rotatingly moving along the forward moving direction (V) of the rolled strip (2) and performing a first wiping operation by contact, so that the residual lubricant layer (Cr) is transferred to the downstream side and the blocking layer (Cb) blocked by the pair (3) of wiping rollers (31, 32) accumulates upstream; - injecting a fluid (4) from at least one blowing point (41) onto the rolled strip (2) in order to strip all or part of the residual lubricant layer (Cr) located downstream of the at least one pair (3) of wiping rollers (31, 32), thereby forming a pressurized fluid flow circulating in a guide channel (66), the guide channel (66) being formed between a guide surface (64) and a cylindrical surface (S) of at least one wiping roller (31, 32), the guide surface (64) extending from downstream of the blowing point (41) to upstream around the wiping rollers (31, 32) while bypassing the wiping rollers, at least part of the stripped residual lubricant layer (Cr) remaining suspended in the fluid flow and at least part of the stripped residual lubricant layer (Cr) adhering to the cylindrical surface (S) of at least one wiping roller (31, 32); - The residual lubricant layer (Cr) is sent back from the downstream to the upstream, a part of the lubricant layer is sent back by the fluid flow circulating in the guide channel (66), another part of the lubricant layer attached to the cylindrical surface (S) is sent back by the rotation of at least one wiping roller (31, 32), and the residual layer is sent back to the layer (Cb) blocked upstream of at least one wiping roller (31, 32).

2. A method according to claim 1, comprising withdrawing all or part of the barrier layer (Cb) of lubricant beyond the lateral edges (21, 22) of the rolled strip (2), and wherein The length of the wiping rollers (31, 32) is greater than the width of the strip (2), the fluid (4) is sprayed from at least one blowing point (41) to at least the entire length of the wiping rollers (31, 32) in the form of at least one continuous fluid blade (42), blown through the space between the wiping rollers (31, 32) and beyond the width of the strip, the fluid blades are configured to prevent a barrier layer (Cb) of lubricant located upstream of the wiping rollers (31, 32) from passing downstream by passing through the space (33) between the wiping rollers (31, 32), the space (33) extending beyond the width of the rolled strip (2).

3. The method according to claim 1 or 2, characterized in that: At least one continuous fluid blade is obtained by ejecting the fluid (4) through at least one slot (5), the slot (5) being formed by the gap between two parts (61, 62) forming the assembly of the box (6), the slot (5) being continuous at least over the entire length of the wiping rollers (31, 32), and the two parts (61, 62) once assembled forming a booster chamber (63) supplied by a pressure source and opening into the slot (5).

4. The method according to claim 1, characterized in that: The blowing point (41) for spraying the fluid (4) is located in a zone (Zs) which extends downstream of the wiping roller over at least the entire width of the rolled strip (2), the blowing point (41) being at a distance of between 20 mm and 70 mm from the contact point in the direction of the strip.

5. The method according to claim 2, characterized in that: At least one blowing fluid blade, oriented at an angle between 30° and 60° relative to the plane of the moving strip, is directed countercurrently relative to said moving strip so as to return said lubricant from downstream to upstream, towards said wiping roller.

6. The method according to claim 3, characterized in that The guide surface (64) is obtained by the external shape of one of the two parts (61, 62) of the box.

7. The method according to claim 1, characterized in that According to the normal direction of the strip, the distance between the blowing point and the strip is between 1 mm and 10 mm.

8. The method according to claim 1, characterized in that The injection of the fluid (4) is carried out downstream of the two wiping rollers (31, 32) of at least one pair (3) of wiping rollers (31, 32), on one side and on the other side of the rolled strip (2).

9. A device (1) for wiping a rolled strip (2) comprising at least one lubricant layer, the wiping device (1) comprising: - at least one pair (3) of two wiping rollers (31, 32) configured to allow the rolled strip (2) to move forward from the upstream side toward the downstream side between each pair (3) of two wiping rollers (31, 32), each wiping roller (31, 32) rotatingly moving along the forward moving direction (V) of the rolled strip and configured to perform a first wiping operation by contact, the upstream side and the downstream side being separated by a contact point of at least one pair (3) of wiping rollers (31, 32) on the rolled strip (2), each pair (3) of wiping rollers (31, 32) being configured to transfer a residual lubricant layer (Cr) to the downstream side and to cause a blocking layer (Cb) blocked by the pair (3) of wiping rollers (31, 32) to accumulate upstream; - at least one blowing point (41) from which a fluid (4) is ejected, which is configured to peel off all or part of the residual lubricant layer (Cr) located downstream of the at least one pair (3) of wiping rollers (31, 32), the wiping device (1) comprising a guide surface (64), the guide surface (64) extending from downstream of the blowing point (41) to upstream around the wiping rollers (31, 32) while bypassing the wiping rollers, each roller comprising a cylindrical surface (S), a guide channel (66) being formed between the guide surface (64) and the cylindrical surface (S), the ejected fluid (4) circulating in the fluid flow in the guide channel (66), at least part of the peeled residual lubricant layer (Cr) remaining suspended in the fluid flow, and at least part of the peeled residual lubricant layer (Cr) adhering to the cylindrical surface (S) of at least one wiping roller (31, 32); - A portion of the lubricant layer is sent back to the upstream side by the fluid flow circulating in the guide channel (66), and another portion of the lubricant layer attached to the cylindrical surface (S) is sent back by the rotation of at least one wiping roller (31, 32), thereby all or part of the peeled residual lubricant layer (Cr) is accumulated on the upstream side of the barrier layer (Cb).

10. The device (1) according to claim 9, characterized in that At least one of the wiping rollers (31, 32) extends over at least the entire width of the rolled strip (2), the wiping rollers (31, 32) are configured to withdraw the barrier layer (Cb) at least partially from the lateral edges (21, 22) of the rolled strip (2), and wherein the length of the wiping roller is greater than the width of the rolled strip (2), and the fluid (4) is sprayed onto at least the entire length of the wiping rollers (31, 32) in the form of continuous fluid blades, thereby preventing the barrier layer (Cb) of the lubricant located upstream of the wiping roller from passing through the space (33) between the two wiping rollers (31, 32) to pass downstream, the space (33) extending beyond the width of the rolled strip (2).

11. The device (1) according to claim 9 or 10, characterized in that The continuous fluid blade is obtained by injecting the fluid (4) through a narrow slot formed by the gap between two parts (61, 62) of the assembly forming the box (6), the narrow slot being continuous at least over the entire length of the wiping roller and the two parts (61, 62) once assembled forming a booster chamber (63) supplied by a pressure source and opening into the narrow slot.

12. According to the device (1) according to claim 9, the blowing point (41) for spraying the fluid (4) is located in the zone (Zs), which extends downstream of the wiping roller over at least the entire width of the rolled strip (2), and the distance between the blowing point (41) and the contact point (P) along the direction of the strip is between 20 mm and 70 mm.

13. The device (1) according to claim 11, characterized in that The guide surface (64) is obtained from the external shape of one of the two parts (61, 62) of the box (6).

14. The device (1) according to claim 9, characterized in that The injection of the fluid (4) is carried out downstream of the two wiping rollers (31, 32) of at least one pair (3) of wiping rollers (31, 32), on one side and on the other side of the rolled strip (2).

15. The device (1) according to claim 9 comprises a crossbeam and a box (60) removable from the crossbeam, the box translating along a sliding link (70) between the box and the crossbeam in a direction parallel to the length of the wiping rollers (31, 32), the box (60) comprising one of the wiping rollers and the blowing point (41).

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