1. A method of lengthening a total top rail length comprising the steps of:
providing a first top rail connected at an end to a first arm of a first connector having a third arm connected to an end support, said first top rail selected from the group of first and second alternative constructions, the first alternative construction having one of an outer perimeter at the end configured to be received within the first arm and the second alternative construction having an inner perimeter about a bore configured to be received about the first arm, with said first arm compatible with both first and second alternative constructions;
disengaging at least the third arm from the first connector;
connecting a second arm to the first arm with said second arm connected to a first end of a second top rail selected from the first and second alternative constructions with the first and second top rails providing a longer total top rail length than before installing the second arm and the second top rail; wherein the first and second arms are characterized by a first outer perimeter at an arm end, a second outer perimeter inwardly disposed away from the arm end, and a first bore extending into the arm end, said first bore having a first inner perimeter at the end and a second inner perimeter inwardly disposed away from the arm end, said second inner perimeter having a same size as the first inner perimeter;
a shoulder extending radially outwardly at the second outer perimeter;
at least one second bore intermediate the first and second outer perimeters and intermediate the first and second inner perimeters extending through the first and second arms;
wherein one of (a) the inner perimeter of the second top rail is positioned over at least a portion of the second arm and connected to the second arm with the at least one connection portion assisting in connecting the top rail to the second arm with the end abutting the shoulder when installed when the second top rail is of the second alternative construction and (b) the outer perimeter of the second top rail received within at least a portion of the bore and connected to the second arm with the at least one second bore assisting in connecting the top rail to the second arm when installed when the second top rail is of the first alternative construction;
and then installing a swing from the second top rail; and
wherein the first connector is compatible with both the first and second alternative constructions.
2. A method of shortening a total top rail length comprising the steps of:
providing a first top rail connected at an end to a first arm of a first connector having a second arm connected to a second top rail, said first and second top rails selected from the group of first and second alternative constructions, the first alternative construction having one of an outer perimeter at the end configured to be received within the respective first and second arm and the second alternative construction having an inner perimeter about a bore configured to be received about the respective first and second arm, with said first and second arms compatible with both first and second alternative constructions;
disengaging the second arm from the first connector along with the second top rail;
wherein the first and second arms are characterized by a first outer perimeter at an arm end, a second outer perimeter inwardly disposed away from the arm end, and a first bore extending into the arm end, said first bore having a first inner perimeter at the end and a second inner perimeter inwardly disposed away from the arm end and having a same size as the first inner perimeter;
a shoulder extending radially outwardly by the second outer perimeter;
at least one second bore intermediate the first and second outer perimeters and intermediate the first and second inner perimeters;
wherein one of (a) the inner perimeter of the second top rail is positioned over at least a portion of the second arm and connected to the second arm with the at least one connection portion assisting in connecting the second top rail to the second arm with the end abutting the shoulder when installed when the second top rail is of the second alternative construction and (b) the outer perimeter of the second top rail received in at least a portion of the bore and connected to the second arm with the at least one connection portion assisting in connecting the second top rail to the second arm when installed when the second top rail is of the first alternative construction;
and then connecting a third arm to the first arm with said third arm connected to an end support to provide a shorter total top rail length than before removing the second arm and the second top rail.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A method of slag-free teeming of metal melt from a metallurgical melt vessel having a discharge opening with a discharge edge, the method comprising the steps of arranging, outside of the melt vessel and closely adjacent to the discharge edge of the vessel discharge opening, of a jetting lance an inclination of which relative to a bath surface in the vessel and spacing from the discharge edge is changeable; and injecting, through the discharge opening of the melt vessel, immediately before start of a teeming process and during the teeming process, of a fluid jet having a high kinetic pulse energy substantially parallel to the bath surface for forcing a slag melt, which is located in a discharge region of the melt vessel, back from a surface of the metal melt to prevent the slag melt from being poured out of the melt vessel, together with the metal melt.
2. A method as set forth in claim 1, further including a step of providing a manipulator for continuously adapting the inclination of the jetting lance relative to the bath surface and the spacing of the jetting lance from the discharge edge to discharge movements of the melt vessel, and a measuring and control system for controlling an operation of the manipulator.
3. A method as set forth in claim 2, wherein an adapting step includes changing the inclination of the jetting lance relative to the bath surface from 15 to 60 and changing the spacing of the jetting lance from the discharge edge from 0.1 m to 3 m.
4. A method as set forth in claim 3, wherein an adapting step includes changing the inclination of the jetting lance relative to the bath surface from 10 to 45 and changing the spacing of the jetting lance from the discharge edge from 0.2 m to 2 m.
5. A method as set forth in claim 1, wherein the injecting step includes injecting an inert gas jet.
6. A method as set forth in claim 5, wherein the inert gas is selected from a group consisting of nitrogen and argon.
7. A method as set forth in claim 1, wherein the injecting step includes injecting a liquid jet.
8. An apparatus for slag-free teeming of a metal melt from a metallurgical vessel having a discharge opening with a discharge edge, the apparatus comprising a jetting lance located outside of the vessel opposite the discharge edge for forcing back slag melt covering metal melt in a discharge region of the vessel; and a manipulator for supporting the jetting lance and for changing an inclination of the jetting lance relative to a bath surface in the vessel and for changing spacing of the jetting lance from the discharge edge.
9. An apparatus as set forth in claim 8, further comprising a measuring and control system for collecting data characterizing a position of the vessel and for controlling operation of the manipulator in accordance with a change of the position of the vessel; and conductor means for connecting the measuring and control system with the vessel and the manipulator.
10. An apparatus as set forth in claim 8, wherein the jetting lance comprises a substantially rectangular slot-shaped nozzle.