What Is Plug in The Refractory Materials

The plug is an important functional component in the metallurgical industry, mainly used to control the flow rate of metal melt. Its standard structure is made of refractory materials, and together with the stopper and nozzle brick, it forms a casting flow control system. In the field of metal pipe processing, metal plug components with threaded structures have been derived, and end sealing processes are achieved through automated devices. This term is technically related to 'plug brick' and belongs to the application category of metallurgical refractory materials.
core structure
The standard plug body is nearly hemispherical, formed by sintering refractory materials, and rigidly connected to the end of the plug rod. In the field of metal tube processing, a component structure has been derived that includes a plug body and a plug nut, which are mechanically connected through threads.
working principle
In the continuous casting system, the plug and nozzle brick form a ball valve mechanism, which adjusts the cross-sectional area of molten steel flow through vertical lifting. The front end of the plug for metal pipes is equipped with a radial groove. When rotating and embedding the pipe, the groove expands to increase the friction force for fixation. When rotating in the opposite direction, the friction force decreases for easy removal.
drive system
The automatic plugging device released in 2024 adopts a servo motor (7) to drive the rotating shaft (8), and transmits torque through the protrusion (14) engaging with the notch of the plug nut. The lateral pushing device (6) controls axial displacement, and cooperates with the bearing (13) and slider (3) to ensure the accuracy of the motion trajectory, achieving a composite motion mode of rotational propulsion.
Material Properties
The refractory plug needs to withstand the erosion of high-temperature molten steel above 1600 ℃ and is made of high alumina or zirconium refractory materials. The plug assembly for metal processing consists of a plug body and a plug nut, which are connected by threads and movable with a rotating shaft.
Process evolution
Traditional manual operation has evolved into automated control, and modern devices monitor the position and force status of the plug in real time through sensors. The rotating shaft is engaged with the notch of the plug nut through the protrusion (14) to achieve power transmission and separation functions. It is matched with the side pushing device (6) to adjust the stroke and synchronously drive the bearing seat (5) and bearing (13) to move as a whole.
Related technology
Plug bricks, as refractory components with similar functions, play a role in fluid sealing in metallurgical kilns. The two components together constitute the technical system for fluid control in the metallurgical industry.