Abstract: An electrode slipping device comprises an upper holder and a lower holder, both holders containing one or more clamping shoes and one or more clamping cylinders in co-operation with the clamping shoes. The clamping shoes are operable between a position where the electrode is clamped and a position where the electrode is unclamped. The clamping cylinder is connected to the electrode holder by first fastening means and to the clamping shoe by second fastening means such that the clamping cylinder can be released from engagement with the holder by unlocking both sets of fastening means.

Abstract: Provided is a pressure ring assembly for contact shoes in an electrode system of an electric arc furnace provided with at least one electrode column assembly. The electrode column assembly comprises a contact shoe ring formed of a plurality of contact shoe elements, a pressure ring formed of a plurality of pressure blocks, and a heat shield formed of a plurality of heat shield segments. An elongated groove is formed on both substantially vertical side edges of each pressure block, and an elongated lock bar is placed in the grooves of two adjacent pressure blocks to join said pressure blocks with each other. The form of the lock bar essentially matches to the form of the grooves of said two adjacent pressure blocks. Each lock bar is locked in place in the grooves by fastening bolts through holes in the pressure blocks.

Abstract: Provided is an arrangement for sealing a bellows cylinder in a pressure block of a pressure ring assembly. The bellows cylinder is located in a cavity formed in the pressure block and is operated by hydraulic fluid to give pressure against a contact shoe of a contact shoe ring arranged on the inside of the pressure ring assembly. The bellows cylinder is sealed to the cavity. A sealing bowl is arranged on the bellows on the inner side of the pressure block. The sealing bowl has an essentially flat surface towards the contact shoe and is provided with a side edge extending into the cavity. A circumferential groove containing a gasket ring is on the side wall of the cavity. A flexible sealing ring is arranged around the gasket ring to give tension and pressure on the gasket ring against the side edge of the sealing bowl.

Abstract: Provided is an arrangement for cooling channels in an electrode column assembly of an electric arc furnace, wherein the lower part of the electrode column assembly is provided with a contact shoe ring formed of a plurality of contact shoe elements, a pressure ring formed of a plurality of pressure blocks, and a heat shield located above the pressure ring and formed of a plurality of heat shield segments. The contact shoe elements and/or the pressure blocks are provided with channels for a cooling liquid to flow therein. The channels made in the material of the contact shoe elements and/or the pressure blocks extend obliquely downwards from the upper ends of said contact shoe elements and/or the pressure blocks near to the lower ends of the same. At least two of said oblique channels join together at their lower ends to form a continuous channel.

Abstract: A method and a system for monitoring clamping pressure exerted by a clamping cylinder to an electrode in an electrode slipping device which comprises an upper annular holder ring and a lower annular holder ring, each comprising at least one clamping assembly including a clamping shoe and clamping cylinder arranged in co-operation so that the clamping shoe is forced into pressure contact with the electrode and released from pressure contact with the electrode by the action of the clamping cylinder. The measuring system comprises a force sensor (30) mounted in connection with a pressing piece (22) that transmits the force created by the clamping cylinder to the clamping shoe. The force sensor can be a strain gage (30) mounted in a cavity (25) provided in the pressing piece (22) or a load cell mounted between the pressing piece (22) and the clamping cylinder.

Abstract: Provided is an arrangement for sealing a bellows cylinder in a pressure block of a pressure ring assembly. The bellows cylinder is located in a cavity formed in the pressure block and is operated by hydraulic fluid to give pressure against a contact shoe of a contact shoe ring arranged on the inside of the pressure ring assembly. The bellows cylinder is sealed to the cavity. A sealing bowl is arranged on the bellows on the inner side of the pressure block. The sealing bowl has an essentially flat surface towards the contact shoe and is provided with a side edge extending into the cavity. A circumferential groove containing a gasket ring is on the side wall of the cavity. A flexible sealing ring is arranged around the gasket ring to give tension and pressure on the gasket ring against the side edge of the sealing bowl.

Abstract: An electrode slipping device comprises an upper holder and a lower holder, both holders containing one or more clamping shoes and one or more clamping cylinders in cooperation with the clamping shoes. The clamping shoes are operable between a position where the electrode is clamped and a position where the electrode is unclamped. The clamping cylinder is connected to the electrode holder by first fastening means and to the clamping shoe by second fastening means such that the clamping cylinder can be released from engagement with the holder by unlocking both sets of fastening means.

Abstract: Provided is a pressure ring assembly for contact shoes in an electrode system of an electric arc furnace provided with at least one electrode column assembly. The electrode column assembly comprises a contact shoe ring formed of a plurality of contact shoe elements, a pressure ring formed of a plurality of pressure blocks, and a heat shield formed of a plurality of heat shield segments. An elongated groove is formed on both substantially vertical side edges of each pressure block, and an elongated lock bar is placed in the grooves of two adjacent pressure blocks to join said pressure blocks with each other. The form of the lock bar essentially matches to the form of the grooves of said two adjacent pressure blocks. Each lock bar is locked in place in the grooves by fastening bolts through holes in the pressure blocks.

Abstract: Provided is an arrangement for cooling channels in an electrode column assembly of an electric arc furnace, wherein the lower part of the electrode column assembly is provided with a contact shoe ring formed of a plurality of contact shoe elements, a pressure ring formed of a plurality of pressure blocks, and a heat shield located above the pressure ring and formed of a plurality of heat shield segments. The contact shoe elements and/or the pressure blocks are provided with channels for a cooling liquid to flow therein. The channels made in the material of the contact shoe elements and/or the pressure blocks extend obliquely downwards from the upper ends of said contact shoe elements and/or the pressure blocks near to the lower ends of the same. At least two of said oblique channels join together at their lower ends to form a continuous channel.

Abstract: A method and a system for monitoring clamping pressure exerted by a clamping cylinder to an electrode in an electrode slipping device which comprises an upper annular holder ring and a lower annular holder ring, each comprising at least one clamping assembly including a clamping shoe and clamping cylinder arranged in co-operation so that the clamping shoe is forced into pressure contact with the electrode and released from pressure contact with the electrode by the action of the clamping cylinder. The measuring system comprises a force sensor (30) mounted in connection with a pressing piece (22) that transmits the force created by the clamping cylinder to the clamping shoe. The force sensor can be a strain gage (30) mounted in a cavity (25) provided in the pressing piece (22) or a load cell mounted between the pressing piece (22) and the clamping cylinder.