Vesuvius Crucible Company

Pascal Dubois

Eric Hanse

Mark K Fishler

Jean-Marie Koten

Claude Dumazeau

The present invention concerns a one-piece stopper rod whose gas tightness is improved. In particular, the stopper rod of the present invention has a body of refractory material comprised at least partially of a refractory material relatively impermeable to gases.

Stopper rod

Molten steel transfer element and its manufacturing

The stopper rod for regulating the flow of a liquid has a body traversed by an axial channel and having at one end a porous nose fed with gas from the channel. The nose has a free space in the form of a hemisphere-shaped slot or lattice network communicating with the channel for delivery of gas thereto. Preferably, a plurality of spaced-apart bridges of solid material connect the two faces of the free space in order to increase the strength of the porous nose.

Stopper rod with an improved gas distribution

A one-piece refractory stopper rod has an axial bore formed therein for the introduction of inert gas into molten steel within a tundish. A metal bushing insert is copressed into the refractory stopper rod and has a threaded bore which is positioned coaxially with the bore of the stopper rod body. A metal attachment rod having an axial bore therethrough and a threaded lower shank portion is secured within the threaded bore of the metal bushing insert. The metal attachment rod has an upper threaded shank which is adapted to be secured to a stopper rod lifting mechanism associated with the tundish. The metal rod further includes a flanged portion intermediate the upper and lower shank portions which carries an annular chamfered surface. The annular chamfered surface faces a like annular chamfered surface formed in the bore of the stopper rod to define a gas-tight seal at a sealing interface therebetween. The upper shank includes an internally threaded portion adapted to receive a threaded fitting for the introduction of a pressurized inert gas to the stopper rod bore. The attachment between the metal rod and the refractory stopper rod provides increased strength, while minimizing gas leakage and air infiltration compared to prior stopper rod attachment configurations.

One-piece stopper rod

A one-piece refractory stopper rod has an axial bore formed therein for the introduction of inert gas into molten steel within a tundish. A metal bushing insert is compressed into the refractory stopper rod and has a threaded bore which is positioned coaxially with the bore of the stopper rod body. A metal attachment rod having an axial bore therethrough and a threaded lower shank portion is secured within the threaded bore of the metal bushing insert. The metal attachment rod has an upper threaded shank which is adapted to be secured to a stopper rod lifting mechanism associated with the tundish. The metal rod further includes a flanged portion intermediate the upper and lower shank portions which carries an annular chamfered surface. The annular chamfered surface faces a like annular chamfered surface formed in the bore of the stopper rod to define a gas-tight seal at a sealing interface therebetween. The upper shank includes an internally threaded portion adapted to receive a threaded fitting for the introduction of a pressurized inert gas to the stopper rod bore. The attachment between the metal rod and the refractory stopper rod provides increased strength, while minimizing gas leakage and air infiltration compared to prior stopper rod attachment configurations.

Growing community of inventors

Feignies, France

Pascal Dubois