Protective cover for a starter bar in continuous casting, and starter bar which employs such protective cover in continuous casting

Abstract

 @ Protective cover (10) for a head (12) of a starter bar (11) in continuous casting, which cover is able to protect the inside of the passage for a billet being cooled in an ingot mould (14) during continuous casting and has a jacket-wise shape and encloses the head (12) of the starter bar (11) at least partially, being positioned between such head (12) and the inside of the passage for the billet.
Starter bar (11) for continuous casting, which cooperates with a protective cover (10) that encloses at least a head (12) of a starter bar at least partially at least when such head is inside the passage for a billet being cooled in an ingot mould (14).

Description

[0001] This invention concerns a protective cover for the head of a starter bar in continuous casting and also concerns a starter bar which employs such protective cover in continuous casting.

[0002] To be more exact, the invention concerns an element which safeguards the inside of a continuous casting ingot mould during the initial step of introducing and positioning the starter bar.

[0003] It is known that an ingot mould to cool metal in continuous casting consists of an alloy very expensive as regards the components of the alloy and the processes required.

[0004] It is also known that the inside of the ingot mould suffers damage, sometimes serious damage, owing to the mechanical wear caused by introduction of the heads of starter bars and also by the abrasion of any chills or crystallizers which cooperate with the starter bar.

[0005] When the head of the starter bar and the chills or crystallizers penetrate within the passage of the ingot mould, they cause scratches, dents, impacts and various damages, which not only shorten the life of the ingot mould but also deform its cross section, thus creating at least malformation of a bar issuing continuously therefrom.

[0006] So as to prevent these shortcomings, the present applicant has designed, tested and embodied a device having the function of protecting the inside of the ingot mould temporarily. Such protective cover cooperates with the head of the starter bar and prevents any contact, even of an accidental nature, between the head of the starter bar and the inner cooling channel of the ingot mould through which a billet being cooled passes.

[0007] According to the invention, a jacket having a shape and outer dimensions substantially suitable to cooperate with the inner channel of the ingot mould is introduced into the lower terminal portion of the ingot mould.

[0008] The introduction of such protective jacket may be performed before insertion of the head of the starter bar or in cooperation with insertion of the head of the starter bar. Such protective cover or jacket then acts as a protective cushion between the head of the starter bar and the inside of the ingot mould, thus safeguarding the inside of the latter.

[0009] The protective cover or jacket may have various lengths to suit the form of the crystallizer and the form and conformation of the removable head of the starter bar.

[0010] The protective cover may be made of various materials; thus it may be embodied with plywood, compressed and moulded wood dust, plastic foam, cellular resin or moulded resin, these being some possible but non-restrictive examples, the word "resin" being understood to cover any desired plastic or synthetic material.

[0011] Moreover, the protective cover may consist of a metallic material having a low or very low melting point and in this case will be a non-reusable element.

[0012] The material forming the protective cover will advantageously be suitable not to cause problems during the step of release of the head of the starter bar or else will be positioned and conformed so as to cooperate with the head of the starter bar and possibly to be released together with that head.

[0013] In a preferred embodiment the protective cover will be made of a material suitable to be burned or to be practically destroyed during the casting step or to be rendered so fragile that it can be readily eliminated during the step of extraction of the head of the starter bar.

[0014] According to the invention the protective cover can be fitted to the head of the starter bar before the latter is introduced into the ingot mould, or else it can be applied to the end portion of the ingot mould before introduction of the starter bar thereinto. Application can be performed by hand or by a robot, for instance by means of a manipulator head which withdraws the protective cover from an appropriate storage point.

[0015] The invention is therefore embodied with a protective cover for a head of a starter bar in continuous casting, which cover is able to protect the inside of the passage for a billet being cooled in an ingot mould during continuous casting, being characterized in that it has a jacket-wise shape and encloses the head of the starter bar at least partially, being positioned between such head and the inside of the passage for the billet.

[0016] The invention is also embodied with a starter bar for continuous casting, characterized in that it cooperates with a protective cover that encloses at least a head of the starter bar at least partially at least when such head is inside the passage for a billet being cooled in an ingot mould.

[0017] Let us now see an embodiment of the invention with the help of the attached figures, which give a non-restrictive example and in which:-

Fig. 1 shows the invention applied to a starter bar having a head which is released sideways;

Fig. 2 shows the invention applied to a starter bar having a head which remains embdedded at the end of the billet.

[0018] A starter bar 11 comprising a head 12 with release means 18 is able to cooperate in an ingot mould 14 having an inflow channel of a required section and characteristics.

[0019] The release means 18 may be of various types and are shown in Fig.1 as being of a type for extraction by sideways displacement and recovery of the head, whereas Fig.2 shows a type with lateral movement and an expendable head 12.

[0020] Chills 15 or 115 are included in cooperation with the head 12 of the starter bar 11 and have the function of crystallizers to speed up and accentuate the cooling and engagement of the end of a billet being cast in the ingot mould 14.

[0021] The head 12 of the starter bar 11, the starter bar 11 itself and the crystallizer chills 15 of Fig.1 are of a known type and may be of any desired type, this being unimportant for the purpose of the invention.

[0022] In Fig.1 the chills 15 consist of simple crop ends of round metallic bars, as commonly employed in the art.

[0023] Instead, Fig.2 shows a spiral type of chill or crystallizer 1₁₅. According to the invention this type of embodiment prevents contact between the chill 115 and the wall 14 of the ingot mould; it therefore enables a shorter protective cover 10 to be used since such cover does not need to reach the zone of the chill 115. Pollution of the cast billet by residues of the carbonised protective cover 10 or of gases caused by combustion of the cover is thus avoided.

[0024] A protective cover or jacket 10 is provided to cooperate with the head 12 of the starter bar 11 and is suitable to cooperate with the inside of the ingot mould 14, thus preventing the head 12 of the starter bar 11 and the starter bar 11 itself from knocking or damaging the inside of the discharge channel of the ingot mould 14.

[0025] The protective cover 10 can be applied to the lower part of the ingot mould 14 before the head 12 of the starter bar 11 is introduced thereinto or else can be fitted to the head 12 of the starter bar 11 before the head 12 is introduced into the ingot mould 14.

[0026] The protective cover 10 can be applied by hand or by a manipulator 17 which takes the cover 10 from an appropriate storage point and positions it.

[0027] If a manipulator 17 is provided, rolls 113 at the end of the starter bar will be capable of being opened apart so as to enable the protective cover 10 to be positioned.

[0028] Guide rolls 13 may possibly be spaced apart in such a way as to enable the manipulator 17 to operate without contacting the rolls.

[0029] The length of the protective cover 10 will vary to suit the conformation of the head 12 of the starter bar 11 and the inner conformation of the ingot mould 14.

[0030] Moreover, the protective cover 10 may consist of plywood, compressed and/or moulded wood chips, wood chips plus a filler, glass-reinforced polyester resin, plastic foam or moulded resin, the name "resin" comprising any known type of plastic or synthetic material.

[0031] The protective cover 10 may also be made of any material, even a metallic material, having a low melting point provided that it is soft, so that it will be destroyed at the time of the casting or will be embedded on the end portion of the billet.

[0032] The protective cover 10 will be positioned and conformed advantageously in such a way that it will not hinder the releasing of the head 12 of the starter bar 11 at the time when the starter bar is detached from the billet.

Claims

1 - Protective cover (10) for a head (12) of a starter bar (11) in continuous casting, which cover is able to protect the inside of the passage for a billet being cooled in an ingot mould (14) during continuous casting, being characterized in that it has a jacket-wise shape and encloses the head (12) of the starter bar (11) at least partially, being positioned between such head (12) and the inside of the passage for the billet.

2 - Protective cover (10) as claimed in Claim 1, which is introduced into the inside of the passage in the ingot mould (14) before the head (12) of the starter bar is inserted.

3 - Protective cover (10) as claimed in Claim 1, which is fitted to the head (12) of the starter bar before such head is inserted into the passage for the billet in the ingot mould.

4 - Protective cover (10) as claimed in any claim hereinbefore, which is applied by hand.

5 - Protective cover (10) as claimed in any of Claims 1 to 3, of which the application is mechanized (17).

6 - Protective cover (10) as claimed in any claim hereinbefore, the rolls (113) at the end of which can be opened apart.

7 - Protective cover (10) as claimed in any claim hereinbefore, which is made of a material softer than the material of the inside of the ingot mould (14).

8 - Protective cover (10) as claimed in any claim hereinbefore, which is expendable.

9 - Protective cover (10) as claimed in any claim hereinbefore, which cooperates with a spiral-type chill (115) surrounding the head (12) of the starter bar (11) (Fig.2). 10 - Starter bar (11) for continuous casting, characterized in that it cooperates with a protective cover (10) that encloses at least a head (12) of the starter bar at least partially at least when such head is inside the passage for a billet being cooled in an ingot mould (14).

Drawing