Lance for use in metal manufacturing and casting equipment

Abstract

Lances for use in metal manufacturing and foundry equipment The present invention relates to a lance consisting of a top lance (1t) and a sublance (2) connected to the top lance (1t) and forming a shoulder (1s) between the top lance and the sublance (2). The sublance (2) of the invention is provided with a protective element (3) having a connecting end (2c) opening into a cavity (2v), the protective element (3) being in an initial configuration when at rest, characterized by a maximum outer diameter (D3o), D3o being at most 10% greater than the diameter (D2) of the sublance (2) (D3o≦1.1D2). When the sublance (2) is connected to the lance, the protective element (3) contacts the shoulder (1s) and deforms into a deformed configuration, forming a surface extending over the entire area of ​​the shoulder (1s) that is impervious to molten metal and slag.

Description

Technical Field

[0001] The present invention relates to a lance for immersing a probe in molten metal contained in a metallurgical vessel such as a converter for steelmaking. The lance is of a type comprising a top lance that is reusable and does not contact the molten metal, a probe coupled to the top lance for measuring parameters of the molten metal at its free end, and / or a sample collector for collecting a sample of the molten metal, and a sub lance for holding them. The sub lance is used by being partially immersed in the molten metal and is disposable. When connecting between the top lance and the sub lance, since the top lance has a larger diameter than the sub lance, a shoulder portion is defined. If the molten metal splashes onto the shoulder portion of the top lance, once the metal solidifies, the connection of the new sub lance to the top lance may become unstable. The present invention proposes a sub lance provided with a protective component for preventing the splash of molten metal or slag onto the shoulder region of the top lance. In order to facilitate the storage of the sub lance in the existing rack of the sub lance and also to operate the sub lance by a robot without changing the programming of the robot, the protective component stored in the rack has a diameter similar to the diameter of the sub lance.

Background Art

[0002] The metal manufacturing process is carried out at high temperatures within a metallurgical vessel and, during the residence time, undergoes chemical or physical reactions, whether desired or not, or moves between vessels of molten metal and / or slag. Since the properties of the final metal product thus manufactured strongly depend on process conditions including temperature and pH, and on the occurrence of chemical or physical reactions, whether desired or not, it is important to measure such parameters and, furthermore, to take samples in-situ for further characterization. This operation is generally carried out with a lance comprising a top lance that remains away from the molten metal or slag, and a sub-lance coupled to the top lance and equipped with a probe and / or a sampler at its free end. The top lance is generally made of metal or polymer and is reusable. On the other hand, the sub-lance is generally made of thick cardboard and is disposable.

[0003] For example, steel can be produced from carbon-rich hot metal by the basic oxygen furnace process, where oxygen is blown through the hot metal by a lance (12) (compare with Figure 1) to reduce the carbon content of the alloy and convert it to low-carbon steel. In this process, samples are taken and the parameters of the melt are measured with different sub-lances, at least during oxygen blowing (sometimes referred to as an internal injection sub-lance) and after oxygen blowing (sometimes referred to as an end injection sub-lance), to ensure the production of steel of the desired quality. The internal injection sub-lance typically comprises a sensor capable of measuring the temperature and liquidus of the molten metal, and a sampler for recovering a sample of the metal. The end injection sub-lance typically comprises a sensor for measuring the temperature and oxygen content of the molten metal, and a sampler for recovering a sample of the metal.

[0004] The new sublance is inserted over the coupling part of the top lance until it reaches a shoulder formed by a gripping part of the top lance having a diameter larger than that of the sublance. Due to vibrations occurring during use, the sublance may come off from the shoulder forming a small gap. Molten metal (11) or slag floating on the surface can be agitated for any reason such as the movement of the vessel or, in the case of a steelmaking converter, the spraying of oxygen, generating a splash (11s) that can reach the upper part of the sublance and even the shoulder, or if there is a splash, a gap is created between the shoulder and the upper part of the sublance. The splash of metal or slag solidifies and forms deposits on the surface of the shoulder and / or the coupling part at the height of the gap. When the current sublance is recovered from the top lance and discarded, it is important to scrape off any solid metal deposits from the surface of the shoulder and the coupling part of the top lance so that the next sublance can be properly coupled to the top lance.

[0005] U.S. Patent No. US4566343 and European Patent No. EP3588052 describe solutions for preventing the formation of metal deposits in the gap between the sublance and the shoulder. U.S. Patent No. US4566343 describes an elastic ring seal between the immersion end of the shoulder of the top lance and the upper part of the sublance to reduce the adhesion of frozen metal at the joint between the top lance and the sublance. European Patent No. EP3588052 describes a similar solution using two ring seals arranged circumferentially on top of each other at the end part of the sublance to seal the space between the coupling tap and the end part of the sublance. These solutions protect the gap between the sublance and the shoulder from the splash of metal or slag reaching it. As described above, the gap does not necessarily occur, and these solutions do not protect against metal splashes occurring on the shoulder.

[0006] Korean Patent No. KR101597688 proposes a solution to protect the shoulder of the top lance from metal splashes. The upper end of the sub-lance comprises an inner ring having an inner path suitable for engaging with the coupling part of the top lance, and an outer ring coaxial with and separated from the inner ring, having a diameter larger than that of the inner ring, which matches the diameter of the shoulder and protects it from metal splashes, and an anti-sticking cover is provided. The problem with this solution is that the outer ring has a diameter substantially larger than that of the sub-lance. As a result, the racks conventionally used for storing new sub-lances that are expected to be used are no longer usable without modifying the dimensions of the receiving means to match the dimensions of the anti-sticking cover. Furthermore, to change the shape of the upper end of the sub-lance by the coupling of the anti-sticking cover, it may be necessary to change the programming of the robot used to operate the sub-lances and couple them to or retrieve them from the top lance.

[0007] The present invention proposes a solution to protect the shoulder of the top lance and maintain the shape of the upper part of the sub-lance, which is not significantly improved, in addition to any gap between the shoulder and the sub-lance. This solution has the advantage of being executable by replacing the existing sub-lances in a one-to-one correspondence without any design changes to the existing racks used for storing the sub-lances and without changing the programming of the robot used to operate the sub-lances. This solution has the advantage that the adaptation of the protective part to the surface of the top lance and to the surface of the sub-lance is the result of the deformation of the entire device, rather than the deformation of the surface of the elastic material. This solution has the advantage that the radially expandable protective part expands only after the top lance and the sub-lance are axially joined, thus reducing the possibility of damage during operation and assembly. These and other advantages of the present invention will be continuously presented.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

[0009] The present invention is defined in the appended independent claims. Preferred embodiments are defined in the dependent claims. The present invention relates in particular to a lance for immersing a probe in molten metal, the lance comprising: (A) a top lance, · a gripping part extending along the longitudinal axis (X) and including a distal end of a cross-section perpendicular to the longitudinal axis (X) of diameter (D1), and provided at the distal end, · a coupling part extending coaxially with the longitudinal axis (X) and having a maximum diameter (d1) with D1>d1, the top lance comprising; (B) a sub lance formed by an elongated tube having a cavity configured to just receive the coupling part and extending along the longitudinal axis (X), the cavity extending along the longitudinal axis (X) from an immersion end provided with a probe and / or a sampler to a proximal end coupled to a protective part having a coupling end opening into the cavity, being substantially cylindrical in diameter (d2) with d1≦d2, o the elongated tube having a cross-section of outer diameter (D2) with d1<d2<D2<D1, o the protective part being deformable when a force is applied thereto along the longitudinal axis (X), o the coupling part being inserted into the cavity of the sub lance by the protective part contacting the shoulder, · the protective part having an initial configuration characterized by a maximum outer diameter (D3o) at rest, D3o being at most 10% larger than D2 (D3o≦1.1 D2), preferably at most 5% larger than D2 (D3o≦1.05 D2), more preferably D3o = D2, · When the sublance is coupled to the lance by insertion into the cavity of the coupling part, the protective part contacts the shoulder part, is deformed into a deformed configuration, and forms a surface impermeable to molten metal and slag that extends over an area that inscribes a circle orthogonal to the longitudinal axis (X) with a diameter (D3d) such that D3d ≧ D1, covering the entire area of the shoulder part, and includes the sublance.

[0010] In the first embodiment, the protective part is · an inner tube that is deformable when a compressive force is applied along the longitudinal axis (X), extends along the longitudinal axis (X), and forms an inner path with a diameter (D3i) such that D3i ≧ d1, the inner layer including a plurality of internal slits that are separated from each other and arranged around the inner tube; · an outer tube that is deformable when a compressive force is applied along the longitudinal axis (X) and just surrounds the inner tube, the outer layer including a plurality of external slits that are separated from each other and arranged around the outer tube; · Optionally, one or more peripheral tubes that are deformable when a compressive force is applied along the longitudinal axis (X), are inserted into each other, and just surround the outer tube (3o), each of the one or more peripheral tubes including a plurality of peripheral slits that are separated from each other and arranged around each of the one or more peripheral tubes, the peripheral slits (3i) of two adjacent peripheral tubes not overlapping each other at any point, and the external slits (3o) not overlapping the peripheral slits of the peripheral tube adjacent to the outer tube at any point, and including one or more peripheral tubes; The internal slits (3i) and the external slits (3o) do not overlap each other at any point.

[0011] Preferably, the internal slit and the external slit extend parallel to the vertical axis (X). In an alternative embodiment, the internal slit and the external slit extend obliquely, but not orthogonally, to the vertical axis (X), and the internal slit and the external slit form an angle with the vertical axis, preferably in the range of 10 to 50°, more preferably in the range of 25 to 45°. The inner tube and the outer tube can be made of an elastomeric material, or a plastically deformable metal, or can be in the form of a woven or non-woven fabric made of ceramic, polymer or metal fibers. To reinforce the reproducibility of the deformation of the protective part, the inner tube and / or the outer tube can be provided with creases to control the deformation of the protective part (3) for folding in a reproducible manner. The inner tube and the outer tube can have different heights measured along the vertical axis (X).

[0012] In a second embodiment, the protective part may comprise a tubular part that is deformable when a compressive force is applied thereto along the vertical axis (X). The tubular part extends along the vertical axis (X) and forms an inner path with a diameter (D3i) such that D3i ≧ d1. The tubular part comprises a plurality of slits that are separated from each other and are arranged around the tubular part. In a preferred embodiment, the slits can be arranged in the following two sets: · an upper set that extends from a position adjacent to the connecting end to a position adjacent to half of the height of the tubular part measured along the vertical axis (X), and · a lower set that extends from a position adjacent to the fixed end opposite to the connecting end to a position adjacent to half of the height of the tubular part, and the slits of the upper set are offset with respect to the slits of the lower set.

[0013] The protective parts of the first and second embodiments described above can be cylindrical, or can comprise one or more cylindrical parts and one or more tapered or curved parts arranged along the vertical axis (X).

[0014] In a third embodiment, the protective part · a support ring coupled to the proximal end of the elongated tube, and · A plurality of L-shaped plates each including an outer portion joined to an inner portion at a corner of the L, and rotatably attached, the plurality of L-shaped plates being arranged around a support ring by hinges at or adjacent to the corners of the L-shaped plates. o In an initial configuration of the protective component, each L-shaped plate is biased to rotate such that the inner portion extends radially inward and substantially orthogonally to the longitudinal axis (X), at least partially closing the cavity, and the outer portion abuts against the outer surface of the sublance. o The L-shaped plates are configured to pivot around the hinge (3h) from the initial configuration to a deformed configuration when inserting the coupling part (1c) into the cavity to couple the sublance to the toplance. In the deformed configuration, the inner portion is aligned parallel to the longitudinal axis (X), and the outer portion extends radially and substantially orthogonally to the longitudinal axis (X), overlapping each other to form a continuous screen against splash when the protective component contacts the shoulder. The protective component comprises a plurality of L-shaped plates.

[0015] Each outer portion has a free edge larger than the corner measured orthogonally to the longitudinal axis (X). When the protective component is in the initial configuration, it is preferable that each outer portion curves with a curvature matching the outer diameter (D2) of the connecting end so as to connect to the outer surface of the sublance.

[0016] Similarly, each inner portion has a free edge shorter than the corner measured orthogonally to the longitudinal axis (X). When inserting the coupling part into the cavity and pivoting the L-shaped plates on their hinges, the inner portion is pressed against the wall of the cavity to form an inner path with a diameter (D3i) such that D3i≧d1, and it is preferable that each inner portion curves with a curvature matching the maximum diameter (d1) of the coupling part to enable the insertion of the coupling part.

[0017] The L-shaped plates are preferably sufficiently rigid so as not to deform substantially during normal use of the device, and are preferably made of metal, preferably steel or aluminum, or a ceramic material, or a polymer material.

[0018] The present invention also relates to a sublance for coupling to the coupling portion of the lance. The sublance is formed by an elongated tube that extends along a longitudinal axis (X) and has a cavity configured to just receive the coupling portion. The cavity extends along the longitudinal axis (X) from an immersion end provided with a probe and / or a sampler to a proximal end that is coupled to a protective part (3) having a coupling end (2c) that opens into the cavity (2v). It is substantially cylindrical with a diameter (d2) such that d1 ≦ d2. The sublance is characterized as follows: · The elongated tube has a cross-section with an outer diameter (D2) such that d1 < d2 < D2 < D1, · The protective part is deformable when a force is applied to it along the longitudinal axis (X), · The coupling portion is inserted into the cavity of the sublance by the protective part that contacts the shoulder, · The protective part has an initial configuration characterized by a maximum outer diameter (D3o) at rest. D3o is at most 10% larger than D2 (D3o ≦ 1.1 D2), preferably at most 5% larger than D2 (D3o ≦ 1.05 D2), and more preferably D3o = D2, · When the sublance is coupled to the lance by insertion into the cavity of the coupling portion, the protective part contacts the shoulder and is deformed into a deformed configuration, forming a surface that is impermeable to molten metal and slag, which extends over an area that inscribes a circle with a diameter (D3d) such that D3d ≧ D1, covers the entire area of the shoulder, and extends orthogonally to the longitudinal axis (X) over a distance of at least equal to 1 / 2 D1 from the longitudinal axis (X).

[0019] The protective part is preferably defined in the first, second, or third embodiment as described above.

[0020] The present invention also relates to a protective part for protecting against splashing on the shoulder formed between the distal end of the gripping part and the sublance of the lance. The protective part is ·An inner tube that is deformable when a compressive force is applied along the longitudinal axis (X), extends along the longitudinal axis (X), and forms an inner path having a diameter (D3i) with D3i ≧ d1, wherein the inner layer comprises a plurality of internal slits that are separated from each other and arranged around the inner tube. ·An outer tube that is deformable when a compressive force is applied along the longitudinal axis (X) and just surrounds the inner tube, the outer tube comprising a plurality of external slits that are separated from each other and arranged around the outer tube. ·Optionally, one or more peripheral tubes that are deformable when a force is applied along the longitudinal axis (X), are inserted into each other, and just surround the outer tube, each of the one or more peripheral tubes comprising a plurality of peripheral slits that are separated from each other and arranged around each of the one or more peripheral tubes, and the peripheral slits (3i) of two adjacent peripheral tubes do not overlap each other at any point, and the external slits do not overlap the peripheral slits of the peripheral tube adjacent to the outer tube at any point. The internal slits and the external slits do not overlap each other at any point.

[0021] The protective component is preferably defined in the first, second, or third embodiment as described above.

Brief Description of the Drawings

[0022] To more fully understand the essence of the present invention, reference is made to the following detailed description in conjunction with the following accompanying drawings.

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Embodiments for Carrying Out the Invention

[0023] The present invention relates to a lance for immersing a probe in molten metal. The lance comprises a toplance (1t) and a disposable sublance (2) that holds the probe and is coupled to the toplance (1t).

[0024] The top lance (1t) comprises a reusable gripping part (1h) and a coupling part (1c) coupled to the distal end of the gripping part (1h) and at least partially integrated therewith. The gripping part (1h) extends along the longitudinal axis (X) and has a distal end with a generally substantially circular cross-section orthogonal to the longitudinal axis (X) of diameter (D1). The distal end is provided with a coupling part (1c) that extends coaxially with the longitudinal axis (X) and has a maximum diameter (d1) where D1>d1. The coupling part generally · a fixing element (1f) that is fixed or integrated with the distal end of the gripping part (1h) and defines an exposed area of the distal end that forms a shoulder (1s); · is formed by a probe holder (1p) that extends along the longitudinal axis (X) and has a proximal end reversibly coupled to the fixing element (1f).

[0025] The specified probe holder is reusable a plurality of times without replacement, but due to the severe usage conditions it is subjected to, its quality rapidly deteriorates, and unlike the gripping part (1h) and the fixing element (1f), the probe holder requires replacement at regular intervals.

[0026] The sub-lance (2) is disposable and is formed by an elongated tube (2t) that extends along the longitudinal axis (X) and has a cavity (2v) configured to just receive the coupling part (1c). The cavity extends along the longitudinal axis (X) from an immersion end provided with a probe (2p) and / or a sampler to a proximal end coupled to a protective part (3) that has an opening in the cavity (2v), and is generally cylindrical with a diameter (d2) where d1<d2. The elongated tube (2t) has a generally circular cross-section with an outer diameter (D2) where d1<d2<D2<D1. The protective part (3) is deformable when a force is applied thereto along the longitudinal axis (X). The sub-lance (2) is reversibly coupled to the top lance (1t) to form a lance. Coupling the sub-lance (2) to the top lance (1t) to form the lance of the present invention is achieved by inserting the coupling part (1c) of the top lance (1t) into the cavity (2v) of the sub-lance (2) at the coupling end (2c) of the protective part (3) that contacts the shoulder (1s).

[0027] The gist of the present invention is to provide a protective component, and on the one hand, the device · uses an existing rack for storing the lance and allows the robot to be used without changing its programming, without significantly changing the shape of the coupling end (2c) of a separate (uncoupled) lance, and on the other hand, · covers the entire area of the shoulder and any gap formed between the shoulder (1s) and the lance (2) when the lance is coupled to the shoulder, protecting it from splashes.

[0028] This is achieved by designing the protective component, whereby · the protective component (3) has an initial configuration characterized by a maximum outer diameter (D3o) at rest, where D3o is at most 10% larger than D2 (D3o ≤ 1.1 D2), preferably at most 5% larger than D2 (D3o ≤ 1.05 D2), and more preferably D3o = D2, · when the lance (2) is coupled to the lance by insertion into the cavity (2v) of the coupling part (1c), the protective component (3) contacts the shoulder (1s) and is deformed into a deformed configuration, forming a surface impermeable to molten metal and slag that extends over an area that inscribes a circle with a diameter (D3d) orthogonal to the longitudinal axis (X) such that D3d ≥ D1. In the deformed configuration, the protective component (3) covers the entire area of the shoulder (1s) and extends orthogonally to the longitudinal axis (X) over a distance at least equal to 1 / 2 D1 from the longitudinal axis (X). Top lance (1t)

[0029] The top lance (1t) is a hollow rod that is long enough to be inserted into a metallurgical vessel as shown in FIG. 1. For example, for a steelmaking converter, the top lance (1t) has a length of 10 to 20 m and can be even longer depending on the dimensions of the metallurgical equipment. The top lance is operated by a robot configured to move the lance downward and upward from the metallurgical vessel. The top lance is formed from a gripping part (1h) and a coupling part (1c).

[0030] The gripping portion (1h) extends along the longitudinal axis (X) and has a distal end with a generally circular cross-section perpendicular to the longitudinal axis (X) of diameter (D1). In the vast majority of cases, the cross-section of the distal end is circular, but if it is not circular, the cross-section can be similarly characterized by the hydraulic diameter (Dh1) (not shown) rather than the diameter (D1), where Dh1 = A1 / P1, and A1 and P1 are the area and perimeter of the cross-section of the distal end perpendicular to the longitudinal axis (X). The roundness of the cross-section of the distal end of the gripping portion is not essential in the present invention. However, in practice, the cross-section is generally circular.

[0031] The gripping portion (1h) can be made of metal, polymer, or fiber-reinforced polymer composite material. The gripping portion is designed to withstand use over a significant service time without replacement. The gripping portion can be regarded as an integral part of the metallurgical equipment.

[0032] As shown in Fig. 2(b), the coupling portion (1c) extends coaxially with the longitudinal axis (X) and has a maximum diameter (d1) where D1 > d1. A shoulder (1s) of width (1 / 2(D1 - d1)) is thus formed by the distal end of the gripping portion (1h) and the coupling portion (1c).

[0033] As shown in Fig. 2(a), the coupling portion (1c) generally consists of · a fixing element (1f) that is fixed to or integrated with the distal end of the gripping portion (1h) and defines an exposed area of the distal end that forms the shoulder (1s), and · a probe holder (1p) that extends along the longitudinal axis (X) and has a proximal end reversibly coupled to the fixing element (1f).

[0034] Like the gripping part, the coupling part is generally hollow so as to define a path for accommodating any wiring required by the probe (2p) positioned at the free end of the sublance (2). The coupling part (1c), in particular the free end of the probe holder (1p), may be provided with an electrical connection (1e) (e.g., male plug or female socket) for coupling to the corresponding electrical connection (2e) of any wiring of the probe (2b) when the sublance (2) is coupled to the top lance (1t). Thus, a conductive continuous communication is formed from the probe (2p) along the path passing through the top lance to any control device for recording the measured values by the probe (2p). Since the electrical connection (1e) of the probe holder (1p) can be damaged by the severe operating conditions in a metallurgical vessel where repeated connection / disconnection with a new sublance (2) and being very close to molten metal at very high temperatures and being often exposed to vibrations, the probe holder (1p) must be replaced at regular intervals to ensure a good connection of any wiring.

[0035] The probe holder (1p) can be reversibly coupled to the fixing element (1f) and forms the coupling part (1c) by mechanical means such as threads, insertion pins, snap fits shown in FIGS. 4(a) and 6(a). Sub lance (2)

[0036] The sublance (2) extends along the longitudinal axis (X) and has a cavity (2v) configured to just receive the coupling part (1c). The sublance (2) consists of at least · an elongated tube (2t) including an immersion end and a proximal end, · the probe (2p) and / or a metal or slag sampler being coupled to the immersion end of the elongated tube (2t), · a protective component (3) being coupled to the proximal end of the elongated tube (2t).

[0037] The cavity is generally of a substantially cylindrical shape with a diameter (d2) such that d1 ≦ d2, and extends along the longitudinal axis (X) from the immersion end, which is at least partially closed by the probe (2p), to the coupling end (2c) of the protective part (3) that opens a cavity for receiving the coupling part (1c) of the top lance (1t). The coupling part (1c) of the top lance (1t) can be in contact with the wall of the cavity (2v) and can be provided with gripping means for fixing the sub lance (2) by friction. The sub lance (2) can also be fixed to the coupling part by mechanical means such as threads, insertion pins, snap fits, etc.

[0038] The electrical connection (2e) connected to the electrical connection (1e) of the coupling part (1c) of the top lance is fixable at a corresponding position within the cavity (2v) such that when the sub lance (2) is coupled to the top lance (1t), electrical communication is formed by connecting the electrical connectors (1e, 2e) of the top lance (1t) and the sub lance (2). In this way, the probe (2b) can be electrically coupled to an external control device (not shown).

[0039] The elongated tube (2t) is generally made of cardboard and is closed by a probe at its immersion end. The coupling end (2c) of the elongated tube (2t) of the sub lance (2) generally has a substantially circular cross section with an outer diameter (D2) such that d1 < d2 < D2 < D1. If any one of the cross sections of the coupling part (1t), the cavity (2v) of the sub lance (2), the coupling end (2c), or the distal end of the gripping part (1h) is not circular, the cross section can be defined by the corresponding hydraulic diameter such that dh1 < dh2 < Dh2 < Dh1, and the hydraulic diameter is defined as the ratio of the perimeter to the area of the corresponding cross section (Dh = A / P).

[0040] The gist of the present invention includes providing a fixed protective part (3) at the coupling end of the sublance (2). The protective part has an initial configuration that does not significantly change the external shape dimensions of the sublance at rest. The protective part (3) is deformable into a deformed configuration when a force is applied thereon parallel to the longitudinal axis (X). The force for deforming the protective part (3) shall not significantly exceed the force normally applied to couple the sublance (2) to the top lance (1t). Depending on the embodiment, when the coupling part (1c) of the top lance (1t) is inserted deeper into the cavity (2v), the free end of the protective part (3) shall be deformed from the initial configuration to the deformed configuration until it contacts the shoulder (1s) of the top lance (1t).

[0041] The coupling of various components of the lance (1) according to the present embodiment of the invention may include coupling the probe holder (1p) to the fixing element (1f) to form the coupling part (1c). The probe holder (1p) can be fixed to the fixing element (1f) by threads, insertion pins, snap fits, etc. The coupling part (1c) of the top lance (1t) can then be coaxially inserted into the cavity (2v) of the sublance (2) like a knife into a sheath until the protective part (3) in the initial configuration contacts the shoulder (2h). When a force is applied along the longitudinal axis (X) on the protective part (3), the protective part reaches the deformed configuration. It is essential for the present invention that the protective part (3) reaches the deformed configuration when the coupling between the sublance (2) and the top lance (1t) is completed.

[0042] As shown in FIGS. 2(d), 4(d), and 6(d), when the sublance (2) is coupled to the top lance (1t), the protective part (3) is in a deformed configuration with the free end of the protective part in contact with the shoulder (1s), and extends radially over a region that inscribes a circle orthogonal to the longitudinal axis (X) having a diameter (D3d) such that D3d ≧ D1. For this reason, it includes the entire region of the shoulder (1s). In the deformed configuration, the shoulder (1s) is protected by the protective part (3) from any molten metal splash (11s), and there is no need to rub to remove any solidified metal from the surface of the shoulder (1s). Such a cleaning operation has to be performed manually and can be very cumbersome. Protective part (3) - double tube

[0043] In the preferred embodiment shown in FIGS. 3(a) to 3(e), the protective part (3) is · an inner tube (3i) that is deformable when a compressive force is applied thereto along the longitudinal axis (X), extends along the longitudinal axis (X), and forms an inner path having a diameter (D3i) such that D3i ≧ d1, the inner layer (3i) being provided with a plurality of internal slits (3si) that are separated from each other and arranged around the inner tube (3i), and · an outer tube (3o) that is deformable when a compressive force is applied thereto along the longitudinal axis (X) and just surrounds the inner tube (3i), the outer tube (3o) being provided with a plurality of external slits (3so) that are separated from each other and arranged around the outer tube (3o), and The internal slits (3si) and the external slits (3so) do not overlap each other at any point.

[0044] The protective part (3) optionally comprises one or more peripheral tubes which are deformable when a compressive force is applied along the vertical axis (X), are inserted into each other, and just surround the outer tube (3o), and each of the one or more peripheral tubes is separated from each other and comprises a plurality of peripheral slits arranged over the periphery of each of the one or more peripheral tubes, and the peripheral slits of two adjacent peripheral tubes do not overlap each other at any point, and the external slit (3so) does not overlap with the peripheral slit of the peripheral tube adjacent to the outer tube at any point, and comprises one or more peripheral tubes.

[0045] As shown in FIG. 4(e), the non-overlapping internal and external slits (3si, 3so) are essential in the present invention for the following reasons. In the initial configuration, the protective part is formed by a plurality of stripes of a material having a stripe width measured in the tangential direction (i.e., orthogonal to the vertical axis (X) and the radial direction) defined between two adjacent slits of the initial slit width, resulting in a maximum outer diameter (D3o) with a circumference Pi = π×D3o. In the deformed configuration, the protective part (3) forms a surface that expands into a region that inscribes a circle with a diameter (D3d) where D3o < D3d, resulting in a circumference Pd = π×D3d > Pi. Since the stripe width remains constant when bending the stripes of the material, Pd can be larger than Pi by only increasing the slit width accordingly. The problem with locally wide slits (3si, 3so) is that such openings prevent the surface formed in this way from being impermeable to the splash (11s) of molten metal and slag. For this reason, both the inner tube (3i) and the outer tube (3o) are required to have internal slits (3si) and external slits (3so) that do not overlap each other at any point, so that any locally wide slit in the inner tube or the outer tube is always covered by the stripes of the material of the inner tube or the outer tube respectively, thus defining a surface that is impermeable to the splash (11s) of metal or slag.

[0046] As shown in FIGS. 3(a) to 3(e), the internal slit (3si) and the external slit (3so) can extend parallel to the vertical axis (X). Instead, as shown in FIG. 3(f), the internal slit (3si) and the external slit (3so) can extend obliquely, but not orthogonally, to the vertical axis. In the present embodiment, the internal slit (3si) and the external slit (3so) can form an angle of 10 to 50°, preferably 25 to 45°, with the vertical axis.

[0047] FIG. 3(c) shows an embodiment in which the inner tube (3i) and / or the outer tube (3o) is provided with a fold line (3f) to control the deformation of the protective part (3) for folding in a reproducible manner. The fold line ensures that the tubular part deforms preferentially along the fold line (3f). The fold line (3f) can be formed by a locally thinner wall thickness of the inner tube and / or the outer tube, or by a perforation of the tubular part, and the fold line is defined in this way by a corresponding groove. Since the protective part (3) is connected at one end to the proximal end of the elongated tube (2t) and at the connecting end (2c) to the coupling part of the top lance (1t), the fold line (3f) can enter parallel adjacent to the connecting end (2c) of the one end and the protective part (3). The fold line (3f) can also enter circumferentially at approximately the middle height of the protective part (3), ensuring that in the deformed configuration, the protective part (3) spreads over the entire shoulder area. The preferred positions of the above-described fold line (3f) are shown in FIGS. 3(c) and 4(e).

[0048] As shown in FIG. 3(d), the inner tube (3i) and the outer tube (3o) can have different heights measured along the longitudinal axis (X). In the embodiment of FIG. 3(d), the outer tube (3o) is approximately half the height of the inner tube (3i). In the embodiment of FIG. 3(d), the outer slit (3so) of the outer tube opens at the free edge of the outer tube (3o) closest to the coupling end (2c). The outer slit (3so) that opens at the free edge of the outer tube (3o) closest to the coupling end (2c) can also be added to any outer tube (3o) having a height consisting of 50% to 100% of the height of the inner tube (3i). With this configuration, the inner tube unfolds and spreads the free stripes of the material of the outer tube, which opens like a petal. The space between two adjacent stripes (= petals) of the outer tube is protected by the stripes of the material of the inner tube (3i) that are offset with respect to the stripes of the outer tube.

[0049] As shown in FIGS. 3(a) to 3(d) and FIG. 3(f), the protective part (3) can be cylindrical, or the protective part can comprise one or more cylindrical parts and one or more tapered or curved parts arranged along the longitudinal axis (X), and an embodiment thereof is shown in FIG. 3(e).

[0050] The inner tube (3i) and the outer tube (3o) can be made of an elastomeric material, or a plastically deformable metal, or can be in the form of a woven or non-woven fiber made of ceramic, polymer or metal fiber.

[0051] Figures 4(a) to 4(d) show various steps for attaching the lance according to the present embodiment of the present invention, emphasizing the deformation of the protective part (3) when the sub-lance (2) is coupled to the top lance (1t). Figure 4(a) shows a method of coupling the probe holder (1p) to the fixing element (1f) to form the coupling part (1c) of the top lance (1t). In Figure 4(a), a thread for coupling the probe holder (1p) to the fixing element (1f) is shown. As described above, other coupling means such as a plug pin or a snap fit can be used without affecting the present invention. As shown in Figures 4(b) and 4(c), the coupling part (1c) of the top lance (1t) is inserted into the cavity (2v) of the sub-lance (2) so that the coupling end (2c) of the protective part contacts the shoulder (1s) without deforming the protective part in its initial configuration, like a sword being sheathed. The protective part (3) shown in Figures 4(b) to 4(e) is of the type shown in Figure 3(b) or Figure 3(c), but the same principle applies to any one of the embodiments shown in Figures 3(b) to 3(f). At this stage shown in Figure 4(c), the sub-lance (2) is not yet fully coupled to the top lance (1t). To complete the coupling, the coupling part (1c) has to be deformed deeper into the cavity and further penetrated, and a compressive force is applied along the longitudinal axis (X) onto the protective part (3) so as to reach the deformed configuration. By comparing Figures 4(d) and 4(e), it is clearly seen that when a compressive force is applied along the longitudinal axis (X), the substantially cylindrical protective part of the double tube is clamped with a fastener at the intermediate height (measured along the longitudinal axis (X)) and forms a shape of the type where two inverted funnels are joined to each other at the wide ends of the funnels. The diameter (D3d) at the height of the fold of the stripe of the material has to be at least equal to the diameter (D2) of the distal end of the top lance (D3d ≥ D2). As a result, the height of the protective part (3) measured along the longitudinal axis (X) has to be greater than twice the radial width of the shoulder (1s) formed between the top lance (1t) and the sub-lance (2) (= 1 / 2 (D1 - D2c)), where D2c is the diameter of the coupling end (2c) of the protective part (3). Protective part (3) - single tube

[0052] In an alternative preferred embodiment shown in FIGS. 7(a) and 7(b), the protective part (3) comprises a single tube that is deformable when a compressive force is applied thereto along the longitudinal axis (X). The tubular part extends along the longitudinal axis (X) and forms an inner path with a diameter (D3i) such that D3i ≧ d1. The tubular part (3i) comprises a plurality of slits (3s) that are separated from each other and arranged around the tubular part.

[0053] In the embodiment shown in FIG. 7(a), the slit extends over at least 70%, preferably at least 80%, more preferably at least 90% of the height of the tubular part measured along the longitudinal axis (X).

[0054] In the embodiment shown in FIG. 7(b), the slits (3s) are arranged in the following two sets: · an upper set that extends from a position adjacent to the connecting end (2c) to a position adjacent to half of the height of the tubular part measured along the longitudinal axis (X), and · a lower set that extends from a position adjacent to the fixed end opposite the connecting end (2c) to a position adjacent to half of the height of the tubular part, and the slits (3s) of the upper set are offset with respect to the slits (3s) of the lower set.

[0055] The slits (3s) may extend parallel to the longitudinal axis (X), or alternatively, the extension with respect to the longitudinal axis (X) is oblique but cannot be orthogonal. In the latter embodiment, the slits (3s) form an angle preferably consisting of 10 to 50°, more preferably 25 to 45° with the longitudinal axis. In all cases, the slits are preferably parallel to each other or at least never cross each other.

[0056] As shown in FIGS. 7(a) and 7(b), the tubular part is preferably provided with a fold line (3f) in order to control the deformation of the protective part (3) for folding in a reproducible manner. For example, the fold line (3f) may extend circumferentially at half of the height of the tubular part.

[0057] The tubular component can be cylindrical or can comprise one or more cylindrical portions and one or more tapered or curved portions arranged along the longitudinal axis (X). The tubular component is preferably made of an elastomeric material, or a plastically deformable metal, or is in the form of a woven or non-woven fabric made of ceramic, polymer or metal fibers. Protective component (3) - flower of the stem

[0058] In a preferred alternative embodiment shown in FIGS. 5(a) to 5(e), the protective component (3) comprises · a support ring (3r) coupled to the coupling end (2c) of the sublance (2), and · a plurality of L-shaped plates (3p), each including an outer portion (3po) joined to an inner portion (3pi) at the corner of the L, as compared to FIG. 5(a).

[0059] As shown in FIG. 5(b), the L-shaped plates are rotatably mounted and arranged around the support ring by hinges (3h) at or adjacent to the corners of the L-shaped plates such that the protective component (3) can be changed between an initial configuration and a deformed configuration by rotation of the L-shaped plates (3p) about their respective hinges (3h).

[0060] In the initial configuration of the protective component (3) shown in FIG. 5(c), each L-shaped plate is biased to rotate such that the inner portion (3pi) extends radially inwards and substantially orthogonally to the longitudinal axis (X), at least partially closing the cavity (2v), and the outer portion (3po) abuts against the outer surface of the sublance (2). In the initial configuration, the inner portion (3pi) forms an inner path of diameter (D3i) where D3i < d1. The bias can be created by a spring that pushes the L-shaped plates into the initial configuration as described above. However, the bias can be created very simply by moving the center of gravity of the L-shaped plates such that the L-shaped plates rotate naturally under gravity and reach the configuration described above. Note that since the sublance is generally stored, manipulated, and used with the longitudinal axis (X) being substantially vertical, the influence of gravity can be easily controlled.

[0061] As shown in Fig. 5(b), when the L-shaped plate inserts the coupling part (1c) into the cavity (2v) to couple the sub lance (2) to the top lance (1t), it is configured to pivot around the hinge (3h) from the initial configuration shown in Fig. 5(c) to the deformed configuration shown in Fig. 5(d). As shown in Fig. 5(d), in the deformed configuration, the inner part (3pi) is aligned parallel to the longitudinal axis (X), the outer part (3po) extends radially substantially orthogonal to the longitudinal axis (X), overlaps with each other, and when the protective part (3) contacts the shoulder (1s), it forms a continuous screen against the metal splash.

[0062] As is apparent from Figs. 5(a) and 5(d), each outer part (3po) preferably has a free edge larger than the corner, measured in the tangential direction (i.e., orthogonal to the longitudinal axis (X) and the radial direction). Thus, when the L-shaped plates (3p) pivot around their hinges to reach the deformed configuration (like the blossomed petals of a lotus), all the L-shaped plates contact the adjacent L-shaped plates positioned on one side of them, thereby forming a continuous screen that protects the shoulder (1s) from the splash.

[0063] Each outer part (3po) preferably curves with a curvature that matches the outer diameter (D2) of the coupling end (2c) such that when the protective part (3) is in the initial configuration, each outer part (3po) connects to the outer surface of the sub lance (2). This is illustrated in Figs. 5(c) and 5(e) such that the maximum diameter (D3o) of the protective part (3) does not exceed by more than 10% (D3o ≦ 1.1 D2).

[0064] In a preferred embodiment, each inner part (3pi) has a free edge shorter than the corner, measured perpendicular to the longitudinal axis (X), as is apparent from FIGS. 5(a) to 5(c). Thus, when the protective part (3) is in its initial configuration and the inner parts (3pi) extend radially inwardly, the inner parts do not overlap each other. The inner parts, in the initial configuration, are not coupled to the toplance by the sublance and thus do not need to form a continuous screen when not in use. When the L-shaped plate pivots to reach the deformed configuration, the L-shaped plate should not overlap each other in order to contact the wall of the cavity and, preferably, make the opening of the cavity as large as possible to pass the coupling part (1c) of diameter (d1) through the cavity (2v).

[0065] Each inner part (3pi) preferably has a curvature that matches the maximum diameter (d1) of the coupling part (1c) such that when the coupling part (1c) is inserted into the cavity (2v) and the L-shaped plate (3) pivots on its hinges (3h), the inner part (3pi) is pressed against the wall of the cavity (2v) to form an inner path of diameter (D3i) where D3i≧d1, allowing the insertion of the coupling part (1c).

[0066] The L-shaped plate (3) preferably has sufficient rigidity so as not to deform significantly during normal use of the device. In particular, when the coupling part (1c) is introduced into the cavity (2v) and presses on the inner part (3pi) of the L-shaped plate, the inner part should not bend (significantly) and must have sufficient rigidity to drive the rotation of the L-shaped plate without bending. The L-shaped plate is preferably made of metal, preferably steel or aluminum, or a ceramic material, or a polymer material, and preferably not a rubber-like polymer.

[0067] Figures 6(a) to 6(d) show various steps for the coupling of various components of the lance according to the present embodiment of the present invention, and emphasize the deformation of the protective part (3) when the sub-lance (2) is coupled to the top lance (1t). Figure 6(a) shows a method of forming the coupling part (1c) by coupling the probe holder (1p) to the fixing element (1f) to form the top lance (1t). In Figure 6(a), a thread for coupling the probe holder (1p) to the fixing element (1f) is shown. As described above, other coupling means such as a plug pin or snap fit can be used without affecting the present invention. As shown in Figures 6(b) and 6(c), the coupling part (1c) of the top lance (1t) is inserted into the cavity (2v) of the sub-lance (2) so as to store the blade in the sheath. In the initial configuration, the inner part (3pi) of the L-shaped plate (3p) extends radially inward, partially closing the opening of the cavity (2v) and leaving an opening with a diameter smaller than the diameter (d1) of the coupling part (1c). As a result, when the coupling part (1c) contacts the inner part (3pi) of the L-shaped plate (3p), the coupling part applies a force on the inner part along the longitudinal axis (X), pushing the inner part downward against the wall of the cavity (2v). For this reason, it drives the inclination of the L-shaped plate (3p) and at the same time pulls up the outer part (3po) away from the outer wall of the sub-lance (2). At the stage shown in Figure 6(c), the protective part can reach a deformed configuration or not, depending on how far the inner part (3pi) is pushed against the wall of the cavity (2v). At this stage, the sub-lance (2) is not yet fully coupled to the top lance (1t) because its coupling end (2c) does not contact the shoulder (1s). To complete this coupling, the coupling part (1c) must penetrate deeper into the cavity. When the coupling between the sub-lance (2) and the top lance (1t) is completed, the fact that the protective part (3) has reached a deformed configuration is essential in the present invention.To fully open the "lotus flower" and arrange the outer part (3po) to form a continuous screen, the coupling part (1c) is tapered so that its diameter increases to reach the maximum diameter (d1) at its upper part adjacent to the gripping part (1c) in order to fully press the inner part against the wall of the cavity (2v). Final Opinion

[0068] Various aspects of the present invention including the top lance (1t), the sub lance (2), and the protective part (3) have common points with the protective part characterized as follows: · The protective part (3) has an initial configuration characterized by a maximum outer diameter (D3o) at rest, where D3o is at most 10% larger than D2 (D3o ≦ 1.1 D2), preferably at most 5% larger than D2 (D3o ≦ 1.05 D2), and more preferably D3o = D2. · When the sub lance (2) is coupled to the lance by insertion into the cavity (2v) of the coupling part (1c), the protective part (3) contacts the shoulder (1s) and is deformed into a deformed configuration, forming a surface impermeable to molten metal and slag that extends over an area circumscribing a circle of diameter (D3d) such that D3d ≧ D1, covering the entire area of the shoulder (1s) and extending orthogonally to the longitudinal axis (X) over a distance at least equal to 1 / 2 D1 from the longitudinal axis (X).

[0069] This clearly simple solution offers a great advantage in terms of lance maintenance as it eliminates the need to scrape off any solidified metal or slag splash that would damage the shoulder (1s) of the top lance (1t). At the same time, the prior art sub lance can be replaced by the sub lance (2) of the present invention without changing any of the processes, the rack for storing the spare sub lance (2), or the programming of the robot operating the sub lance. This is possible because in the initial configuration, the protective part (3) does not significantly change the shape of the sub lance. This solution is also implemented quite economically.

Table 1

Claims

1. A lance (1) for immersing a probe in molten metal, comprising: (A) - A gripping portion (1h) extending along a longitudinal axis (X) and having a distal end of a cross-section orthogonal to the longitudinal axis (X) with a diameter (D1); - A top lance (1t) comprising a coupling portion (1c) extending coaxially with the longitudinal axis (X) and having a maximum diameter (d1) with D1 > d1; (B) A sub-lance (2) formed by an elongated tube (2t) having a cavity (2v) extending along the longitudinal axis (X) and configured to just receive the coupling portion (1c); The cavity is substantially cylindrical with a diameter (d2) where d1 ≤ d2, Extending along the longitudinal axis (X) from an immersion end provided with a probe (2p) and / or a sampler to a proximal end coupled to a protective component (3) having a coupling end (2c) opening into the cavity (2v), o The elongated tube (2t) has a cross-section with an outer diameter (D2) where d1 < d2 < D2 < D1, o The protective component (3) is deformable when a force is applied along the longitudinal axis (X), o The coupling portion (1c) is inserted into the cavity (2v) of the sub-lance (2), and at this time the protective component (3) contacts a shoulder (1s), - The protective component (3) has an initial configuration characterized by a maximum outer diameter (D3o) at rest, and D3o is at most 10% larger than D2 (D3o ≤ 1.1 D2), - When the sub-lance (2) is coupled to the top lance by insertion of the coupling portion (1c) into the cavity (2v), the protective component (3) contacts the shoulder (1s) and deforms into a deformed configuration, spreading over a region circumscribing a circle orthogonal to the longitudinal axis (X) with a diameter (D3d) where D3d ≥ D1, forming a surface impermeable to molten metal and slag and covering the entire area of the shoulder (1s). The lance (1) is characterized by this.

2. The protective component (3) is: - An inner tube (3i) that is deformable when a compressive force is applied along the longitudinal axis (X), extends along the longitudinal axis (X), and forms an inner path with a diameter (D3i) where D3i ≥ d1. The inner tube (3i) is separated from each other and comprises a plurality of internal slits (3si) arranged around the inner tube (3i). ・An outer tube (3o) that is deformable when a compressive force is applied along the longitudinal axis (X) and that just surrounds the inner tube (3i), the outer tube (3o) being separated from each other and having a plurality of external slits (3so) arranged over the circumference of the outer tube (3o). ・Optionally, one or more peripheral tubes that are deformable when a compressive force is applied along the longitudinal axis (X), are inserted into each other, and just surround the outer tube (3o), each of the one or more peripheral tubes being separated from each other and having a plurality of peripheral slits arranged over the circumference of each of the one or more peripheral tubes, the peripheral slits of two adjacent peripheral tubes not overlapping each other at any point, and the external slits (3so) not overlapping the peripheral slits of the peripheral tube adjacent to the outer tube at any point, comprising one or more peripheral tubes. The lance according to claim 1, wherein the internal slit (3si) and the external slit (3so) do not overlap each other at any point.

3. The lance according to claim 2, wherein the internal slit (3si) and the external slit (3so) extend parallel to the longitudinal axis (X).

4. The lance according to claim 2, wherein the internal slit (3si) and the external slit (3so) extend obliquely but not orthogonally to the longitudinal axis (X).

5. The lance according to any one of claims 2 to 4, wherein the inner tube (3i) and the outer tube (3o) can be made of an elastomeric material, or a metal deformable by plastic deformation, or in the form of a woven or non-woven fiber made of ceramic, polymer or metal fiber.

6. The lance according to any one of claims 2 to 5, wherein the inner tube (3i) and / or the outer tube (3o) is provided with a fold line (3f) to control the deformation of the protective part (3) for folding in a reproducible manner.

7. The lance according to any one of claims 2 to 6, wherein the inner tube (3i) and the outer tube (3o) have different heights measured along the longitudinal axis (X).

8. The protective component (3) comprises a tubular component that is deformable when a compressive force is applied thereto along the longitudinal axis (X). The tubular component extends along the longitudinal axis (X) and forms an inner path with a diameter (D3i) such that D3i ≧ d1. The tubular component is separated from each other and comprises a plurality of slits (3s) arranged around the tubular component. The lance according to claim 1.

9. The slits (3s) are arranged in the following two sets, - an upper set extending from a position adjacent to the connecting end (2c) to a position adjacent to half of the height of the tubular component measured along the longitudinal axis (X), - a lower set extending from a position adjacent to the fixed end opposite the connecting end (2c) to a position adjacent to half of the height of the tubular component, and the slits (3s) of the upper set are offset with respect to the slits (3s) of the lower set. The lance according to claim 8.

10. The protective component (3) is - cylindrical or - comprises a plurality of cylindrical portions, or - comprises one or more cylindrical portions and one or more tapered or curved portions arranged along the longitudinal axis (X). The lance according to any one of claims 2 to 9.

11. The protective component (3) is - a support ring (3r) coupled to the proximal end of the elongated tube (2t), and - comprises a plurality of L-shaped plates. The plurality of L-shaped plates (3p) each include an outer portion (3po) joined to an inner portion (3pi) at the corner of the L, and are a plurality of L-shaped plates rotatably mounted. At or adjacent to the corner of the L-shaped plate, they are arranged around the support ring by hinges (3h), o In the initial configuration of the protective component (3), each L-shaped plate is biased to rotate such that the inner portion (3pi) extends radially inward substantially perpendicular to the longitudinal axis (X), at least partially closing the cavity (2v), and the outer portion (3po) abuts against the outer surface of the sub-lance (2). o The L-shaped plate is configured to pivot around the hinge (3h) from the initial configuration to the deformed configuration when inserting the coupling portion (1c) into the cavity (2v) to couple the sub lance (2) to the top lance (1t). In the deformed configuration, the inner portion (3pi) is aligned parallel to the longitudinal axis (X), and the outer portion (3po) extends radially and substantially orthogonally to the longitudinal axis (X). When they overlap each other and the protective part (3) contacts the shoulder (1s), they form a continuous screen against splash. The lance according to claim 1.

12. Each outer portion (3po) has a free edge larger than the corner when measured orthogonal to the longitudinal axis (X). When the protective part (3) is in the initial configuration, each outer portion (3po) curves with a curvature that matches the outer diameter (D2) of the coupling end (2c) so as to contact the outer surface of the sub lance (2). The lance according to claim 11.

13. Each inner portion (3pi) has a free edge shorter than the corner when measured orthogonal to the longitudinal axis (X). When inserting the coupling portion (1c) into the cavity (2v) and pivoting the L-shaped plate (3) on their hinges (3h), the inner portion (3pi) is pressed against the wall of the cavity (2v) to form an inner path with a diameter (D3i) where D3i≧d1. Each inner portion (3pi) curves with a curvature that matches the maximum diameter (d1) of the coupling portion (1c) so as to enable the insertion of the coupling portion (1c). The lance according to claim 11 or 12.

14. The L-shaped plate (3) is sufficiently rigid so as not to be substantially deformed during normal use of the protective part. The lance according to any one of claims 11 to 13.

15. A sublance (2) for coupling to the coupling portion (1c) of the lance (1t) according to any one of claims 1 to 14, wherein the sublance (2) extends along the longitudinal axis (X) and is formed by an elongated tube (2t) having a cavity (2v) configured to just receive the coupling portion (1c), the cavity being substantially cylindrical with a diameter (d2) such that d1≦d2, and extending along the longitudinal axis (X) from an immersion end provided with a probe (2p) and / or a sampler to a proximal end coupled to a protective component (3) having a coupling end (2c) opening into the cavity (2v), - The elongated tube (2t) has a cross-section with an outer diameter (D2) such that d1<d2<D2<D1, - The protective component (3) is deformable when a force is applied thereto along the longitudinal axis (X), - The coupling portion (1c) is inserted into the cavity (2v) of the sublance (2), and at that time the protective component (3) contacts the shoulder (1s), - The protective component (3) has an initial configuration characterized by a maximum outer diameter (D3o) at rest, where D3o is at most 10% larger than D2 (D3o≦1.1 D2), - When the sublance (2) is coupled to the lance by insertion of the sublance (2) into the cavity (2v) of the coupling portion (1c), the protective component (3) contacts the shoulder (1s) and is deformed into a deformed configuration, forming a surface impermeable to molten metal and slag that extends over an area circumscribing a circle with a diameter (D3d) such that D3d≧D1, covering the entire area of the shoulder (1s) and extending orthogonally to the longitudinal axis (X) over a distance equal to at least 1 / 2 D1 from the longitudinal axis (X), characterized in that the sublance (2).

16. The protective component (3) is the sublance (2) according to claim 15, defined in any one of claims 2 to 7, any one of claims 8 to 10, or any one of claims 11 to 14.

17. A protective component (3) for protecting against splashing between the distal end of the front gripping portion (1h) and the front shoulder (1s) formed between the sublance (2) of the lance according to claim 1, wherein the protective component (3) - An inner tube (3i) that is deformable when a compressive force is applied along the longitudinal axis (X), extends along the longitudinal axis (X), and forms an inner path with a diameter (D3i) such that D3i ≥ d1. The inner layer (3i) is provided with a plurality of internal slits (3si) that are separated from each other and arranged around the inner tube (3i). - An outer tube (3o) that is deformable when a compressive force is applied along the longitudinal axis (X) and just surrounds the inner tube (3i). The outer layer is provided with a plurality of external slits (3so) that are separated from each other and arranged around the outer tube (3o). - Optionally, one or more peripheral tubes that are deformable when a force is applied along the longitudinal axis (X), are inserted into each other, and just surround the outer tube (3o). Each of the one or more peripheral tubes is provided with a plurality of peripheral slits that are separated from each other and arranged around each of the one or more peripheral tubes. The peripheral slits of two adjacent peripheral tubes do not overlap each other at any point, and the front external slit (3so) does not overlap the peripheral slits of the peripheral tube adjacent to the outer tube at any point. It comprises one or more peripheral tubes. The internal slit (3si) and the external slit (3so) do not overlap each other at any point. A protective component (3).

18. The protective component according to claim 17, as defined in any one of claims 2 to 7 and claim 10.

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