GB2260189A

GB2260189A - A tapping for blast furnaces

Info

Publication number: GB2260189A
Application number: GB9220293A
Authority: GB
Inventors: Manfred Dango; Albrecht Baeumer
Original assignee: Dango and Dienenthal Maschinenbau GmbH
Current assignee: Dango and Dienenthal Maschinenbau GmbH
Priority date: 1991-09-26
Filing date: 1992-09-25
Publication date: 1993-04-07
Anticipated expiration: 2012-09-25
Also published as: DE4131982C2; GB2260189B; LU88173A1; GB9220293D0; JPH0688110A; DE4131982A1

Abstract

The tapping hole boring machine for metallurgical containers such as blast furnaces (2) comprises as essential components a carriage (1) which can swing out of the rest position into the working position and vice versa, and a boring and impact hammer preferably formed as a reaction hammer, movable by motor on the carriage (1) for driving and withdrawing a boring, drift or tapping rod (10) into and from a tapping hole (4) of the furnace (2) filled with a plugging mass (3), and one or more guides (15, 16) arranged on the carriage (1) (movable in the direction of the longitudinal axis of the carriage or positionally fixed) for protecting the rod (10) against buckling on account of large thrust forces when driving it in by the thrust drive (6, 7). <IMAGE>

Description

1 A TAPPING HOLE BORING MACHINE FOR METALLURGICAL CONTAINERS, ESPECIALLY

BLAST FURNACES This invention relates to a tapping hole boring machine for metallurgical containers, especially blast furnaces, with a carriage which can be swung from the rest position into the working position and vice versa, and a boring and impact hammer preferably formed as a reaction hammer movable by motor on the carriage for driving in and withdrawing a boring, drift or tapping rod into and out of a tapping hole of the container filled with a plugging mass. Such tapping hole boring machines are known from e.g. DE 3 111 260 C2.

Tapping holes of metallurgical furnaces, especially blast furnaces, have been opened up according to an older procedure by boring with a boring rod or by pre boring by means of the boring rod and then breaking through the remaining wall with a drift rod.

According to a newer method the tapping hole is no longer bored out but a is steel rod, called a tapping rod, is driven through to the interior of the furnace a predetermined time after plugging the tapping hole, by means of a boring hammer formed as a reaction hammer, and is withdrawn again from the tapping hole at the tapping time by the boring hammer operating then in the rearward direction.

The boring hammers currently available on the market, formed as reaction hammers with a pneumatic or hydraulic drive create a lot of noise wIlich generally exceeds the upper limit allowed by the management. This creation of noise is a consequence of the physical principle of operation of such hammers and cannot be reduced by primary measures. Secondary sound protection measures are also only of limited effect and result in disproportionally high costs.

In connection with the avoidance of the operating noise of the boring hammer, extensive investigations have been made to drive the tapping rod into the tapping hole of the furnace with a pneumatic or hydraulic drive and to withdraw it at tapping time, without use of a boring hammer or at least to reduce the necessary operating time of the boring hammer. In order to achieve this, a significant increase in the thrust and withdrawal force acting on the tapping rod is necessary, compared with the mode of operation using a boring hammer. This is not possible in the tapping hole7 boring machine of the type referred to, according to t DE 3 111260 C2, since the tapping rod would buckle under the thrust forces of the order of magnitude needed.

The invention is based on the problem of so developing the construction of the tapping hole boring machine of the type referred to that a tapping rod can be driven into the tapping hole of a blast furnace without a boring hammer, or at the most with short operation of the boring hammer.

This problem is solved according to the invention by a tapping hole boring machine according to claim 1.

The dependent claims are directed towards advantageous embodiments of the invention.

The tapping hole boring machine according to the invention is distinguished by the following advantages:

1 The drive force acting directly on the tapping rod through the thrust and withdrawal drive of the boring hammer in driving in and withdrawing the tapping rod into and from the tapping hole of a blast furnace or the like are of such magnitude that the boring hammer does not have to turned on or only a short operation of the boring hammer is needed, while buckling of the tapping rod is prevented by the guides therefor arranged on the carriage in a fixed position or slidably. The boring hammer formed as a reaction hammer can be connected in simple manner to the thrust and withdrawal drive of the boring hammer, formed as a circulating chain, through the coupling device for the tapping rod fitted to the boring hammer, if required both in driving in the tapping rod and also in withdrawing the same into or from the tapping hole.

The invention will now be described with reference to schematic drawings of two embodiments of a tapping hole boring machine, the same or like parts of the two illustrated embodiments being designated by the same reference numerals.

These show:

Figure 1 a side view of a first embodiment of a tapping hole boring machine in the limit position remote from the furnace of a boring hammer movable on a carriage, before driving in a tapping rod, Figure 3 Figure 5 Figure 6 Figure 2 a side view corresponding to Figure 1 with the boring hammer in the limit position near to the furnace, after fully driving in the tapping rod, an enlarged cross-sectional view of the carriage according to the line III-III of Figure 1, Figure 4 a side view of a second embodiment of a tapping hole boring machine in the limit position remote from the furnace of the boring hammer, before driving in a tapping rod, in part a partial plan view of the tapping hole boring machine according to Figure 4 and in part a partial section according to the line V-V of Figure 6, and an enlarged cross-sectional view of the camiage according to the line VI-VI of Figure 4 with the guide for the tapping rod open and closed.

The tapping hole boring machine according to Figures 1 to 3 comprises a carriage 1, which can be swung relative to the tapping hole 4 of a furnace 2, sealed with a plugging mass 3, in conventional manner in the arrow directions a, b up and away out of the working position into the rest position and vice versa. A boring hammer 5, preferably formed as a reaction hammer, is movable on the carriage 1 by means of a thrust and withdrawal drive, which is formed by a chain 7 driven by a hydraulic motor 6, from a limit position S' remote from the furnace into a limit position 5" near to the furnace and vice versa.

A coupling part 8 for the boring hammer 5 is fitted on the drive chain 7 and the boring hammer 5 is fixed thereto by its end facing the furnace 2 and also fixed thereto is the coupling device 9 of the boring hammer 5 for receiving a tapping rod 10.

The end 11 of the carriage 1 near to the furnace is anchored by a retainer 12 on the furnace casing 13. In addition a guide 14 for the tapping rod 10 is fitted in a fixed position to the end 11 of the carriage 1 near to the furnace. 71e guide 14 can be opened when, after driving the tapping rod 10 into the tapping hole 4 of the furnace 2, the whole tapping hole boring machine is to be removed as rapidly as possible from the furnace region with the pouring channel still filled with red-hot iron.

There are further arranged on the carriage 1 two guides 15, 16 movable in the direction of movement c, d of the tapping rod 10, for protecting the rod from buckling on account of the large thrust forces which occur when driving into the tapping hole 4 by the drive chain 7.

The guides 15, 16 each comprise a slider 17 suspended from the carriage 1, with a receiving opening 19 for the tapping rod 10 open downwardly and closable by a pivoted yoke 18.

At the beginning of the driving in operation, the boring hammer 5 is in the limit position 5' remote from the furnace and the two spaced guides 15, 16 for the tapping rod 10 assume the positions 15', 16' on the carriage 1 remote from the furnace, between the boring hammer 5 in the limit position 5' and the end 11 of the carriage 1 near to the furnace. The thrust force needed to drive the tapping rod 10 into the tapping hole 4 of the furnace 2, generated by the hydraulic motor 6, is transmitted directly from the drive chain 7 to the coupling device 9 at the end of the boring hammer 5 near to the furnace and thence to the tapping rod 10. If necessary, the impact mechanism of the boring hammer 5 can be turned on briefly at any time during the thrusting movement, in order to assist the driving in operation.

During the driving in operation, in which the endangered buckling length of the tapping rod 10 between the coupling device 9 and the fixed guide 14 at the end 11 of the carriage 1 near to the furnace is continuously reduced, the guide 15 is firstly engaged by the boring hammer 5 and pushed thereby up to the second guide 16, and then the two guides 15, 16 are moved into the limit positions 15", 16" near to the furnace determined by the forward limit position 5 " of the boring hammer 5.

The withdrawing force needed to pull the tapping rod 10 out of the tapping hole 4.of the furnace 2 is applied by the hydraulic motor 6 and transmitted to the tapping rod 10 through the drive chain 7 and the coupling device 9, while the impact mechanism of the boring hammer 5 can be turned on at any time during the withdrawal of the tapping rod 10.

On withdrawing the tapping rod 10 from the tapping hole 4 in the direction of the arrow d the guides 15, 16 are engaged in turn by respective dogs 20, 21 fixed at intervals on the drive chain 7 and which engage on corresponding abutments 22, 23 of the guides 15, 16, and the guides are moved back on the carriage 1 by the dogs 20, 21 of the drive chain 7 from the positions 15 ", 16 " near to the furnace into the positions 15', 16' remote from the furnace.

The ta pping hole boring machine according to Figures 4 to 6 is, in contrast to the embodiment of Figures 1 to 3 described above, equipped with a guide 24 in a fixed position.

71e positionally fixed guide 24 comprises two support ar-ms 26 arranged ppposite one another on the two sides of the path of movement of the tapping rod 10; each can be pivoted about an axis 25-25 substantially perpendicular to the longitudinal axis of the carriage into and out of the path of movement of the tapping rod and they are each provided with a receiving channel 27 for the tapping rod 10 and are each biased into the pivoted in position by a return spring 28. The support arms 26, formed as cranked arms, are pivotally mounted on a cross member 29 is fixed to the carriage 1. With the support arms 26 pivoted in the receiving channels 27 form a nearly closed cylindrical guide for the tapping rod 10.

71e pivoting movement of the support arms 26 is controlled by two actuating bars 30 fixed to the boring hammer 5 and which cooperate with guide rollers 31 on the support arms 26.

On driving the tapping rod 10 into the tapping hole 4 of the furnace 2, the support arms 26 of the positionally fixed guide 24, which is fixed on the carriage 1 approximately at the half stroke point of the tapping rod 10, are pivoted out at the correct time sufficiently for the boring hammer 5 to pass the guide 24 without hindrance, this being effected by the actuating bars 30 which are fixed to the boring hammer 5 travelling from the limit position 5' remote from the furnace into the limit position Y' near to the furnace. 71e actuating bars are made long enough for the guide rollers 31 of the two support arms 26 to bear on the actuating bars 30 also in the limit position Y' of the boring hammer 5 near to the furnace.

As a modification of the embodiment of a tapping hole boring machine just described, the support arms could be pivoted by a pneumatic or hydraulic drive cylinder, the command for the pivoting movement being provided by means of a limit switch through the boring hammer moving in the direction of the furnace.

The control is effected by means of an electromagnetic valve and allows the opening of the guide independent of the position of the boring hammer, in order to facilitate insertion and removal of the tapping rod.

Furthermore the positionally fixed support device can be equipped with a pneumatic cylinder which either acts against the return springs for the independent opening of the support device or replaces the return springs, with suitable control. This solution has the advantage that no sensitive components such as limit switches and cables are necessary on the carriage, in spite of the capability of external control.

Claims

1. A tapping hole boring machine for metallurgical containers, especially blast furnaces, with a carriage which can be swung from the rest position into the working position and vice versa, and a boring and impact hammer preferably formed as a reaction hammer movable by motor on the carriage for driving in and withdrawing a boring, drift or tapping rod into and out of a tapping hole of the container filled with a plugging mass, characterized by one or more guides (15, 16,.24) arranged on the carriage (1) along the path of movement of the boring, drift or tapping rod (10) for protecting the rod (10) against buckling on account of large thrust forces when driving it in by the thrust drive (6, 7).

2. A tapping hole boring machine according to claim 1, 'characterized by guides (15, 16) movable on the carriage (1) in the direction of movement (c, d) of the tapping rod (10).

3. A tapping hole boring machine according to claim 1 and claim 2, characterized by a displacement of the guides (15, 16) in the direction of the furnace (2) by the boring hammer (5) when driving the tapping rod (10) into the tapping hole (4) and a displacement in the opposite direction when withdrawing the rod (10) from the tapping hole (4) by dogs (20, 21) on the thrust and retracting drive of the boring hammer (5), formed as a circulating chain (7).

4. A tapping hole boring machine according to claim 3, characterized by a connecting part (8) fitted to the drive chain (7), on which part are fitted the boring hammer (5), at its end facing the furnace (2), and the coupling device (9) for the tapping rod (10).

5. A tapping hole boring machine according to claim 1, characterized by at least one guide (24) arranged at a fixed position on the carriage (1) in the direction of movement (c, d) of the tapping rod (10) and which can be advanced into and retracted from or be swung into and out of the path of movement of the tapping rod (10).

6. A tapping hole boring machine according to claim 5, characterized in that the positionally fixed guide (24) comprises two support arms (26) opposite one another on the two sides of the path of movement of the tapping rod (10), which arms can pivot into and out of the path of movement of the tapping rod (10) and are biased in the pivoted in direction and each have a receiving channel (27) for the apping rod (10), wherein the receiving channels (27) form a nearly closed cylindrical guide for the tapping rod (10) with the support arms (26) pivoted in, in that the support arms (26) are each mounted to pivot in and out about an axis (2525) substantially perpendicular to the longitudinal axis of the carriaae, and in that the pivotal movement of the support arms (26) is controlled by two actuating bars (30) fixed on the boring hammer (5) and cooperating with guide rollers (31) on the support arms (26).

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