The disclosure relates to a tap hole plug gun comprising a material chamber for receiving a plugging compound and a mouthpiece for being placed on a tap hole, the mouthpiece being connected to the material chamber or to a nozzle part disposed on the material chamber by means of an unlockable connection device.
Tap hole plug guns of the kind mentioned above are used to close the tap openings of reduction furnaces or smelting furnaces, such as blast furnaces for producing pig iron and low-shaft furnaces for smelting nonferrous metals, ferroalloys, etc. During plugging, the tap hole plug gun is pressed against the front of the furnace with great force by means of a pivoting device, the contact pressure being maintained until the plugging compound injected into the tap hole opening of the furnace through the mouthpiece of the tap hole plug gun has hardened.
To operate the tap hole plug gun, the plugging compound is received in a material chamber of the tap hole plug gun, which is typically a cylindrical space, and is injected from the material chamber into the tap hole opening through the mouthpiece of the tap hole plug gun by means of a plugging piston. A typically conical nozzle part connected to the material chamber by means of a connecting device in an exchangeable manner can be disposed between the material chamber and the mouthpiece to reduce the diameter of the tap hole plug gun in the area of transition between the material chamber and the mouthpiece. Great forces act on the connection device during ejection because of the substantially reduced diameter in the section from the nozzle part to the mouthpiece, two essential requirements to be met by the connecting device being that the connection device has to be easy to detach for replacement of the nozzle part while being stable enough to reliably absorb the forces acting during ejection without impairing detachability.
Another unlockable connection device can be provided between the nozzle part and the mouthpiece, while the mouthpiece can also be connected directly to the material chamber by means of an unlockable connection device, i.e., without an interposed nozzle part, if the tap hole plug gun is a smaller tap hole plug gun whose material chamber has a comparatively small diameter.
WO 2011/089054 A1 discloses a tap hole plug gun having a nozzle part connected to the material chamber via a flange connection. In the known tap hole plug gun, another flange connection is provided between the nozzle part and the mouthpiece. The flange connections connect the nozzle part to the material chamber and the nozzle part to the mouthpiece in a connection plane perpendicular to the ejecting direction, connecting bolts distributed across the circumference of the tap hole plug gun and extending parallel to the ejecting direction connecting two opposite flanges disposed on the material chamber and on the nozzle part and on the nozzle part and the mouthpiece so as to realize the flange connections. Since the connecting bolts extend parallel to the ejecting direction, their number and size have to be such that the ejection forces can be safely transmitted via the bolts without this endangering the sealing of the tap hole plug gun in the connection plane or there even being a risk of the components of the bolt connections failing.
The large number of bolt connections distributed across the circumference of the tap hole plug gun for realizing the flange connections results in a corresponding amount of installation work when exchanging the nozzle part or the mouthpiece or when servicing the tap hole plug gun, which requires only temporary removal of the mouthpiece for accessing the discharge opening of the material chamber or of the nozzle part.
Hence, the object of the present disclosure is to propose a tap hole plug gun that has a connection device formed between the mouthpiece and the material chamber or between the mouthpiece and a nozzle part potentially disposed on the material chamber, said connection device making a reliable mechanical connection possible while allowing the mouthpiece to be exchanged or the tap hole plug gun to be serviced with relatively little installation effort.
To attain said object, the tap hole plug gun according to the disclosure has the features of claim 1.
According to the disclosure, the connection device is realized as a hinged joint arrangement between the mouthpiece and the material chamber or between the mouthpiece and the nozzle part, the hinged joint arrangement having two opposite hinged joints each having a joint bolt which connects a joint plate arrangement of the nozzle part to a joint plate arrangement of the mouthpiece and can be removed from the connection to the joint plate arrangements, the joint bolts having, at least in sections, a wedge portion which is wedge-shaped in the direction of a joint axis, and a joint plate of each hinged joint being provided with a jamb portion of a joint eyelet for receiving the wedge portion of the joint bolt, said jamb portion being wedge-shaped in the direction of the joint axis.
A hinged joint arrangement of this configuration for detachably connecting the mouthpiece to the material chamber or to the nozzle part enables easy removal of the mouthpiece by removing the joint bolts. During maintenance, removing only one of the joint bolts is an option, which means that there is a choice between which of the opposite hinged joints is to serve as a pivot bearing for pivoting the mouthpiece open or closed. The hinged joint arrangement according to the disclosure enables an identical configuration of the two opposite hinged joints.
Moreover, the interaction of the wedge portions of the joint bolts with the associated wedge-shaped jamb portions on the joint eyelets of the joint plates allows an axial sealing force to be achieved between opposite axial ends of the nozzle part and of the mouthpiece.
A particularly reliable configuration of the hinged joint arrangement becomes possible if the joint plate arrangements of the nozzle part each have two joint plates which are disposed at a vertical distance and between which a joint plate of the mouthpiece is disposed so as to realize the hinged joint, said joint plate having the joint eyelet with the wedge-shaped jamb portion.
Preferably, an axial engagement device is formed between opposite axial connecting edges of the nozzle part and of the mouthpiece, a defined radial relative alignment of the nozzle part and of the mouthpiece thus being present independent of the hinged joint arrangement.
Simultaneous radial sealing becomes possible if the engagement device has a ring web which is formed on one connecting edge and engages into a complementary ring groove formed on the other connecting edge.
Preferably, the ring web has a truncated cross section, which enables an axial sealing force and a radial sealing force simultaneously.
Hereinafter, a preferred embodiment of the disclosure will be explained in more detail with reference to the drawing.
Nozzle part 23 enables a reduction of the inner diameter of tap hole plug gun 20 as required for the area of transition from material chamber 21 to mouthpiece 24, and for this purpose is truncated, in particular obliquely truncated in the exemplary embodiment at hand. As can be understood in particular from the illustration in
As becomes clear in particular from a combined view of
As becomes clear from a comparison of
Hence, bolt connections 40, 41 secure connecting projections 28, 30 in their radial position, preventing compression forces occurring in tap hole plug gun 20 from severing the form-fitting engagement established between connecting projections 28, 30 and serving to absorb the axial portion of the compression forces.
For realizing the form-fitting engagement, a ring segment web 45 (
As shown in
As can be seen in particular from the illustration in
As can be seen in particular from
A shielding device 76 is disposed on lower part 32 of material chamber 21 and on lower part 36 of nozzle part 23, in particular for protection against heat radiation emitted against tap hole plug gun 20 below tap hole plug gun 20.
As can be seen in particular from the sequence of
As shown in
In the configuration illustrated in
In the event that one of the two joint bolts 67 is removed from one of hinged joints 60 or 61, mouthpiece 24 can pivot on one side about joint axis 77, which is formed by joint bolt 67 remaining in hinged joint 60 or 61, for maintenance purposes, for example. Thus, as illustrated in
As can be seen from
Preferably, ring web 73 has a truncated cross-section that is complementary to the cross-section of ring groove 74. The wedge effect made possible between jamb portions 68 of joint plates 65 and wedge portions 70 of joint bolts 67 can generate an axial sealing force between nozzle part 23 and mouthpiece 24 by inserting joint bolts 67 into joint eyelets 69 of joint plates 65, an effectively sealing position of mouthpiece 24 and nozzle part 23 relative to each other being achieved by means of said axial sealing force.
This application represents the national stage entry of PCT International Application No. PCT/EP2019/056266 filed on Mar. 13, 2019, the entire contents of which is incorporated herein by reference for all purposes.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2019/056266 | 3/13/2019 | WO | 00 |