EP3024611B1 - Cooled strand guide roller - Google Patents

Description

Field of engineering

The present invention relates to a strand guide roll for guiding a steel strand in a continuous casting machine and a method for cooling the strand guide roll in the continuous casting machine by a cooling medium.

State of the art

From the WO 2004/065040 A1 a cooled strand guide roller is known in which a cooling medium first cools a bearing in a left bearing block, the cooling medium flows from the left bearing block through the roller to the right bearing block, and there again a bearing cools. A disadvantage of the known strand guide roller that the cooling medium has to be introduced from a bearing block in each case via a rigid or flexible connecting piece and a rotary feedthrough in the role or on the opposite side again. This restricts the robustness of the roll.

How the design can be simplified, so that can be dispensed with in particular sensitive rotary unions, is not apparent from the Scriptures.

Summary of the invention

The object of the invention is to present a cooled strand guide roller for guiding a steel strand in a continuous casting machine, which is characterized by a particularly simple design and is particularly robust and prone to failure. As a result, the term of the strand guide roller to be extended even in harsh conditions in the continuous casting machine.

Another object of the invention is to provide a method for cooling a strand guide roll in a continuous casting machine, in which the cooling medium cools the two bearing blocks, and the cooling medium cools the bearings and the cylindrical roller shell of the roll on the way between the two bearing blocks. As a result, a so-called "peripherally cooled" strand guide role is created, which is due to the compactness and reliability also for billet, bloom and profile continuous casting machines. As a result, crack-sensitive steel grades can be cast into long products on a continuous casting machine.

• einen linken und einen rechten Lagerbock;
• eine stillstehende Achse, wobei die stillstehende Achse mit dem linken und mit dem rechten Lagerbock drehsteif verbunden ist;
• einen zylindrischen Rollenmantel und ein linkes und ein rechtes Lager, wobei der drehbare Rollenmantel durch das linke und rechte Lager gegenüber der stillstehenden Achse drehbar gelagert ist; und
• einen Wasserleitmantel, wobei der Wasserleitmantel Kühlwasser von einem linken Hohlraum zwischen der Achse und dem Wasserleitmantel im Bereich des linken Lagers in einen Längsraum zwischen dem Wasserleitmantel und dem Rollenmantel, entlang des Längsraums in axialer und radialer Richtung, und vom Längsraum in einen rechten Hohlraum zwischen dem Wasserleitmantel und der Achse im Bereich des rechten Lagers leiten kann.

The first object is achieved by a strand guide roller for guiding a steel strand in a continuous casting machine, comprising:

• a left and a right bearing block;
• a stationary axle, wherein the stationary axle is rigidly connected to the left and to the right bearing block;
• a cylindrical roller shell and a left and a right bearing, wherein the rotatable roller shell is rotatably supported by the left and right bearings relative to the stationary axis; and
• a Wasserleitmantel, the Wasserleitmantel cooling water from a left cavity between the axis and the Wasserleitmantel in the region of the left bearing in a longitudinal space between the Wasserleitmantel and the roller shell, along the longitudinal space in the axial and radial directions, and from the longitudinal space in a right cavity between the Conduit and the axis in the area of the right bearing can conduct.

Due to the design of the strand guide roller with a stationary axle, which is torsionally rigidly connected to both the left and the right bearing block, a particularly smooth-running role is created with a low moment of inertia. As a result, the contact between the lateral surface of the roller and the cast strand even under transient casting conditions be reliably maintained. The torsionally rigid connection can for example be positive (eg by a feather key) or non-positively (eg by a shrink or press-fit connection or by friction). The left bearing is cooled by the cooling water in the left cavity. The surface of the cylindrical roller mantle is cooled by the cooling water in the longitudinal space, wherein a particularly uniform temperature distribution is achieved by the guidance of the cooling water in the axial and tangential direction. Finally, the right bearing is cooled by the cooling water in the right cavity.

• ein zylinderförmiges Rohr, dessen Wandstärke kleiner als die Längserstreckung des zylinderförmigen Rohrs ist;
• mehrere tangentiale Außenstege, die sich auf der äußeren Mantelfläche des Rohrs in axialer Richtung über die Längserstreckung des Rohrs erstrecken, wobei zwei aufeinanderfolgende Außenstege einen Abstand in axialer Richtung zueinander aufweisen; und
• ein axialer Außensteg, der sich auf der äußeren Mantelfläche des Rohrs in axialer Richtung über die Längserstreckung des Rohrs erstreckt, wobei jeweils zwei aufeinanderfolgende tangentiale Außenstege abwechselnd eine Durchtrittsöffnung für das Kühlwasser auf der in axialer Richtung gesehen rechten oder linken Seite des axialen Außenstegs aufweisen.

The Wasserleitmantel can be made particularly simple and efficient sheet metal parts, if it has:

• a cylindrical tube whose wall thickness is smaller than the longitudinal extent of the cylindrical tube;
• a plurality of tangential outer webs, which extend on the outer circumferential surface of the tube in the axial direction over the longitudinal extension of the tube, wherein two successive outer webs have a distance in the axial direction to each other; and
• an axial outer web which extends on the outer circumferential surface of the tube in the axial direction over the longitudinal extension of the tube, wherein each two successive tangential outer webs alternately have a passage opening for the cooling water in the axial direction seen right or left side of the axial outer web.

Through the Wasserleitmantel a cooling medium is introduced from a left cavity between the Wasserleitmantel and a stationary axis in a longitudinal space between the roll shell and the Wasserleitmantel, performed in the longitudinal space in both the axial and tangential direction, and from the longitudinal space in a right cavity between the Wasserleitmantel and the stationary axle. This not only makes a particularly even distribution of the surface temperature of the roll mantle, but also cooled the left and right bearings.

The cylindrical tube, the tangential outer webs and the axial outer web are preferably bent sheet metal parts, wherein the outer webs are connected by joining (eg., Soldering, welding or gluing) to the pipe.

• ein zylinderförmiges Rohr, dessen Wandstärke kleiner als die Längserstreckung des zylinderförmigen Rohrs ist;
• zumindest ein spiralförmiger Außensteg, der sich auf der äußeren Mantelfläche des Rohrs zumindest einmal spiralförmig um die Längserstreckung des Rohrs erstreckt.

An alternative water-conducting jacket points to:

• a cylindrical tube whose wall thickness is smaller than the longitudinal extent of the cylindrical tube;
• at least one spiral-shaped outer web, which extends on the outer circumferential surface of the tube at least once spirally around the longitudinal extent of the tube.

In this variant of the water guide jacket, the cooling medium is passed through at least one, possibly a plurality, spiral outer web in the tangential and axial direction along the roll shell, whereby also sets a very uniform distribution of the surface temperature on the roll shell. The spiraled outer land can either be joined to the pipe by joining, or machined out of the pipe by milling or turning.

It is particularly expedient if the Wasserleitmantel has at least one, preferably two or more, inner web, which extends from the inner circumferential surface of the tube in the radial direction to the stationary axis. As a result, a so-called "hydraulic short circuit" between two cavities is prevented, each located between the left end of the axis and the roller shell and the right end of the axis and the roller shell. As a result, the cooling medium is forced to flow from the left cavity along the longitudinal space to the right cavity, whereby a high heat dissipation from the cast product is ensured.

It is advantageous if the left and the right bearing block each have a bore for receiving the stationary axle wherein the bearing block has at least one, preferably closed, cavity in the tangential direction around the bore. Through the cavity in the bearing block, which is flowed around by the cooling medium, both the bearing block itself and a sealing element for the sealing are cooled to the outside.

For introducing the cooling medium from the bearing block in the axis, it is expedient if the cavity in the bearing block has a substantially radial stub for guiding the cooling water from the bearing block in the axis. Although a radial stub has the shortest length, it is not necessary for the stub to be exactly radial.

It is advantageous if each half of the stationary axle has in the longitudinal direction a separate axial line for conducting the cooling medium and a radial branch line connected thereto into a cavity.

For fluid-tight sealing of the left bearing relative to the left cavity or the right bearing relative to the right cavity at least one sealing element is provided in each case.

A simple fluid-tight seal can eg by a so-called. Prelonring (see, eg WO 2011/117383 A1 for the execution of seals on strand guide rollers with Prelon rings), through sealing rings or through rotary seals such as sliding rings.

The protection of the bearing from the environment can be done, for example, by radial shaft seals or labyrinth seals. Of course, other variants for the sealing of bearings are also known to the person skilled in the art.

• einen linken und einen rechten Lagerbock mit einem linken und einem rechten Lager;
• eine stillstehende Achse;
• einen zylindrischen Rollenmantel, wobei der drehbare Rollenmantel über das linke und rechte Lager gegenüber der stillstehenden Achse drehbar gelagert ist;

umfasst, aufweisend folgende Verfahrensschritte:

• Umströmen der stillstehenden Achse innerhalb des linken Lagerbocks durch das Kühlmedium; anschließend
• Eintritt des Kühlmediums vom linken Lagerbock in die stillstehende Achse;
• Durchströmen einer ersten axialen Leitung der stillstehenden Achse;
• Eintritt in einen Hohlraum der Strangführungsrolle;
• Umströmen des Hohlraums, wobei das linke und das rechte Lager gekühlt werden;
• Durchströmen einer zweiten axialen Leitung der stillstehenden Achse;
• Eintritt des Kühlmediums von der stillstehenden Achse in den rechten Lagerbock;
• Umströmen der stillstehenden Achse innerhalb des rechten Lagerbocks durch das Kühlmedium.

The second object is achieved by a method for cooling a strand guide roller in a continuous casting by a cooling medium, wherein the strand guide roller

• a left and a right bearing block with a left and a right bearing;
• a stationary axle;
• a cylindrical roller shell, wherein the rotatable roller shell is rotatably supported via the left and right bearings relative to the stationary axle;

comprising, comprising the following method steps:

• Flowing around the stationary axle within the left bearing block by the cooling medium; subsequently
• Entry of the cooling medium from the left bracket into the stationary axle;
• Flowing through a first axial line of the stationary axle;
• Entry into a cavity of the strand guide roller;
• Flowing around the cavity, wherein the left and right bearings are cooled;
• Flowing through a second axial line of the stationary axle;
• Entry of the cooling medium from the stationary axle into the right bearing block;
• Flow around the stationary axle within the right bearing block through the cooling medium.

By the, preferably in the circumferential direction complete, flow around the stationary axle within the left and right bearing block of the respective bearing block is cooled. By flowing around the cavity and the two bearings are cooled on the axis and the roller shell.

• das Kühlmedium vom linken Hohlraum in einen Längsraum zwischen einem Wasserleitmantel und dem Rollenmantel einströmt;
• das Kühlmedium in axialer Richtung den Längsraum durchströmt; und anschließend
• das Kühlmedium vom Längsraum in den rechten Hohlraum einströmt.

In order to avoid the above-mentioned hydraulic short circuit, it is advantageous if the cavity has a left cavity, a longitudinal space, and a right cavity, wherein

• the cooling medium from the left cavity flows into a longitudinal space between a Wasserleitmantel and the roller shell;
• the cooling medium flows through the longitudinal space in the axial direction; and subsequently
• the cooling medium flows from the longitudinal space into the right-hand cavity.

As a result, a so-called peripherally cooled strand guide roller is formed.

To achieve a particularly uniform surface temperature on the roller shell, it is advantageous if the cooling medium in flowing through the longitudinal space in addition to the axial movement performs a tangential movement about the stationary axis.

Brief description of the drawings

• Fig 1 eine perspektivische Ansicht einer erfindungsgemäßen Strangführungsrolle
• Fig 2 eine Ansicht von rechts der Strangführungsrolle nach Fig 1
• Fig 3 eine Ansicht von rechts einer Variante zur Strangführungsrolle nach Fig 1
• Fig 4 eine Schnittdarstellung entlang der Linien A-A von Fig 2
• Fig 5 eine perspektivische Ansicht einer ersten Variante eines Wasserleitmantels
• Fig 6 eine perspektivische Ansicht einer zweiten Variante eines Wasserleitmantels
• Fig 7 ein Längsschnitt zu Fig 6

Further advantages and features of the present invention will become apparent from the following description of non-limiting embodiments, wherein the figures show:

• Fig. 1 a perspective view of a strand guide roller according to the invention
• Fig. 2 a view from the right of the strand guide role after Fig. 1
• Fig. 3 a view from the right of a variant of the strand guide role after Fig. 1
• Fig. 4 a sectional view along the lines AA of Fig. 2
• Fig. 5 a perspective view of a first variant of a Wasserleitmantels
• Fig. 6 a perspective view of a second variant of a Wasserleitmantels
• Fig. 7 a longitudinal section too Fig. 6

Description of the embodiments

The Fig. 1 shows a perspective view of a non-driven strand guide roller 30 according to the invention for supporting and guiding a steel strand with billet or billet profile in a continuous casting machine. The steel strand, not shown, is supported on the cylindrical surface of the rotatable roller shell 12, wherein the roller shell 12 via in Fig. 1 not shown bearings 13a, 13b (see Fig. 4 ) is rotatably mounted on the stationary axle 11.

In Fig. 2 is a side view of the strand guide roller 30 from Fig. 1 shown. Each bearing block 10a, 10b can be connected via eccentric bores and not shown fastening means, such as screws, with the strand guide or a segment of the strand guide.

In Fig. 3 schematically a right bearing block 10b and the flow through the bearing block with a cooling medium (eg water) is shown. In this case, the cooling water, as shown by the lower arrow, from below into the bearing block 10b and flows in a vertical direction upwards. Subsequently, the cooling water is deflected four times by 90 °, so that the cooling water in a closed cavity 14, the stationary axle 11 can flow completely around. This ensures uniform cooling of the axle 11 or of the roller mantle 12 connected to the axle. The cooling water can enter from the cavity 14 via a radial stub 15 in an axial line 22 within the axis 11. In addition, grease or oil may be introduced via the grease bore 21 'for lubricating the bearing 13b. Via the drainage holes 24, which is arranged in the sealed area between the grease- or oil-filled storage space and the water-filled cavity 14,14a, 14b, both water or fat / oil or water can be transported via the stationary shaft 11 in the non-pressurized environment. This allows an operator from the outside immediately check the operability of the strand guide roller 30 without having to engage in the role.

In Fig. 4 It is shown that the cooling water from the stub 15 via an axial line 22 and a radial bore in a cavity 14, 14 a, which is bounded by the stationary shaft 11, the rotatable bearing housing 23, and the Wasserleitmantel 1, can occur. Through the cavity 14a, which is connected to the longitudinal space 16 between the Wasserleitmantel 1 and the inner circumferential surface of the roll mantle 12, the preload seal 17 and the bearing 13a is cooled. The preload seal has on its inner lateral surface three dynamic sealing elements (concretely sliding rings) and on its outer lateral surface two static sealing elements (here O-rings). In operation, the co-rotating preload seal (also called the prelo ring) 17 is supported on the stationary axle 11. In order to prevent contamination of the bearings 13a, 13b, the bearing 13a is sealed relative to the bearing block 10a via a labyrinth seal 19 and a radial shaft sealing ring 18. The same applies to the right bearing 13b in the bearing block 10b. The in Fig. 6 1 has the following functions: On the one hand, a hydraulic short circuit between the left cavity 14a and the right cavity 14b is prevented. As a result, the cooling water is forced to flow from the left cavity 14a via the longitudinal space 16 to the right cavity 14b. By flowing through the longitudinal space 16 in the axial and tangential direction, a uniform surface temperature of the roller shell 12 and the steel strand resting thereon is achieved. The stationary axle 11 is non-positively connected to a bearing block 10a, 10b. The bearing housing 23 is connected via a tight weld with the roller shell 12.

In Fig. 5 a first variant of the water jacket 1 is shown. The Wasserleitmantel has a thin-walled cylindrical tube 2 made of sheet metal, an axial outer web 6, which extends in the axial direction x over the length of the tube 2, and a plurality, arranged in the axial direction one behind the other, spaced tangential outer webs 5. To the cooling water in the Longitudinal space between the water jacket 1 and force the roller shell, the conductive jacket also comprises on the inner circumferential surface of the tube 2 at least one, here two, inner webs 9. Thus, the inside of the roller shell 12 is cooled by the cooling water in the direction shown by the arrows.

The Fig. 6 shows a second variant of the water jacket 1. Here, the cooling water flows around the Wasserleitmantel 1 or the inner surface of the roller shell 12 in a spiral shape.

The Fig. 7 shows a longitudinal section through the Wasserleitmantel 1 from the Fig. 4 and 6 , The spiral outer web 8 and the inner webs 9 are welded to the tube 2.

While the invention has been further illustrated and described in detail by the preferred embodiments, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

LIST OF REFERENCE NUMBERS

1

Wasserleitmantel

2

pipe

3

Wall thickness

4

longitudinal extension

5

tangential outer bridge

6

axial outer bar

7

Through opening

8th

spiral outer bridge

9

inner web

10a, 10b

bearing block

11

axis

12

roller shell

13a, 13b

camp

14, 14a, 14

cavity

15

stub

16

longitudinal space

17

Prelon ring

18

Radial shaft seal

19

labyrinth seal

20

circumferential groove

21

drilling

21 '

grease hole

22

axial line

23

bearing housing

24

drain hole

30

Strand guide roller

r

radial direction

t

tangential direction

x

axial direction

Claims (13)

1. Strand guide roller (30) for guiding a steel strand in a strand casting machine, comprising

   - a left-hand (10a) and a right-hand bearing block (10b);

   - a stationary axle (11), wherein the stationary axle (11) is connected to the left-hand (10a) and to the right-hand bearing block (10b) in a torsionally rigid manner;

   - a cylindrical roller casing (12) with a left-hand (13a) and a right-hand bearing (13b), wherein the roller casing (12) is rotatably supported relative to the stationary axle (11) by means of the left-hand and right-hand bearings (13a, 13b); and

   - a water conducting casing (1), wherein the water conducting casing (1) can conduct cooling water from a left-hand cavity (14a) between the axle (11) and the water conducting casing (1) in the region of the left-hand bearing (13a) into a longitudinal space (16) between the water conducting casing (1) and the roller casing (12), along the longitudinal space (16) in an axial (x) and a tangential (t) direction, and from the longitudinal space (16) into a right-hand cavity (14b) between the water conducting casing (1) and the axle (11) in the region of the right-hand bearing (13b).
2. Strand guide roller according to claim 1, characterised in that the water conducting casing (1) comprises:

   - a cylindrical tube (2) whose wall thickness (3) is less than the longitudinal extent (4) of the cylindrical tube (2);

   - a plurality of tangential outer ribs (5) which extend in an axial direction (x) on the outer casing surface of the tube (2) over the longitudinal extent (4) of the tube (2), wherein two adjacent outer ribs (5) are separated from each other by a distance in an axial direction (x);

   - an axial outer rib (6) which extends in an axial direction (x) on the outer casing surface of the tube (2) over the longitudinal extent (4) of the tube (2), wherein any two adjacent tangential outer ribs (5) alternately have a passage (7) for the cooling water on the right-hand or the left-hand side of the axial outer rib (6) as viewed in an axial direction (x).
3. Strand guide roller according to claim 1, characterised in that the water conducting casing (1) comprises:

   - a cylindrical tube (2) whose wall thickness (3) is less than the longitudinal extent (4) of the cylindrical tube (2);

   - at least one spiral outer rib (8) which extends around the longitudinal extent (4) of the tube (2) at least once in the form of a spiral on the outer casing surface of the tube (2) .
4. Strand guide roller comprising a water conducting casing (1) according to one of claims 2 or 3, having at least one and preferably two inner ribs (9) which extend from the inner casing surface of the tube (2) in a radial direction (r) as far as the stationary axle (11).
5. Strand guide roller according to one of the preceding claims, wherein the left-hand (10a) and/or the right-hand bearing block (10b) has a hole (21) in each case for accommodating the stationary axle (12), characterised in that the bearing block (10a, 10b) comprises at least one preferably closed cavity (14, 14a, 14b) in a tangential direction (t) around the hole (21).
6. Strand guide roller according to claim 5, characterised in that the cavity (14, 14a, 14b) in the bearing block (10a, 10b) comprises an essentially radial (r) branch line (15) for guiding the cooling water from the bearing block (10a, 10b) into the axle (12).
7. Strand guide roller according to one of the preceding claims, characterised in that each half of the stationary axle (11) has an axial line (22) for conducting coolant, and an essentially radial branch line (15) which is connected thereto and leads into a cavity.
8. Strand guide roller according to one of the preceding claims, characterised in that the left-hand and/or the right-hand bearing (13a, 13b) is sealed in a leak-proof manner relative to the cavity (14, 14a, 14b) by means of a sealing element in each case.
9. Strand guide roller according to claim 8, characterised in that the sealing element is a Prelon ring (17).
10. Strand guide roller according to one of the preceding claims, characterised in that the stationary axle (11) has a drain hole (24), wherein this connects the external surroundings to a sealed region.
11. Method for cooling a strand guide roller (30) in a strand casting machine using a coolant, wherein the strand guide roller (30) comprises

    - a left-hand (10a) and a right-hand bearing block (10b) with a left-hand (13a) and a right-hand bearing (13b);

    - a stationary axle (11);

    - a cylindrical roller casing (12), wherein the rotatable roller casing (12) is rotatably supported (13a, 13b) relative to the stationary axle (11) by means of the left-hand and right-hand bearings;

    having method steps as follows:

    - the coolant flowing around the stationary axle (11) within the left-hand bearing block (10a); then

    - the coolant entering the stationary axle (11) from the left-hand bearing block (10a);

    - flowing through a first axial line (22) of the stationary axle (11);

    - entering a cavity (14) of the strand guide roller (30);

    - flowing around the cavity (14), wherein the left-hand and right-hand bearings (13a,13b) are cooled;

    - flowing through a second axial line (22) of the stationary axle (11);

    - the coolant entering the right-hand bearing block (10b) from the stationary axle (11);

    - the coolant flowing around the stationary axle (11) within the right-hand bearing block (10b).
12. Method according to claim 11, characterised in that the cavity (14) comprises a left-hand cavity (14a), a longitudinal space (16), and a right-hand cavity (14b), wherein
    the coolant flows from the left-hand cavity (14a) into a longitudinal space (16) between a water conducting casing (1) and the roller casing (12);
    the coolant flows through the longitudinal space (16) in an axial direction (x); and then
    the coolant flows from the longitudinal space (16) into the right-hand cavity (14b).
13. Method according to claim 12, characterised in that the coolant also performs a tangential movement (r) around the stationary axle (11) as it flows through the longitudinal space (16).

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