Electric Power Research Institute Incorporated

William Frederick Newell, Jr

David Wayne Gandy

Ramaswamy Viswanathan

Kent Coleman

James W Hales

Gregory J Frederick

James Franklin Turner

Shane J Findlanl

Roger Allen Swain

Richard M Tilley

Accordingly, the present invention provides a weld filler composition for joining different alloy steel pieces with substantially different chromium content, such as joining low alloy ferritic steel to high alloy ferritic steel, low alloy ferritic steel to austenitic stainless steel, or high alloy ferritic steel to austenitic stainless steel, and a method using the same. In one embodiment, the present invention provides a composition for a weld filler comprising nickel, iron, and chromium, which collectively comprise at least 50% by weight of the weld filler; niobium, carbon, manganese, molybdenum, and silicon, which collectively comprise no more than 50% by weight of the weld filler, and a niobium to carbon ratio of approximately 20 or less.

Weld filler for welding dissimilar alloy steels and method of using same

This invention relates to a method and apparatus for controlling the composition of a weld. More particularly it relates to welding using an electric circuit, thereby creating a weld puddle, and adding at least one filler that is electrically independent from the electric circuit to the weld puddle at a controllable rate to obtain a target weld composition. The filler can be added to the extent limited by practical weld puddle geometry and, thus, the method and apparatus also facilitate increased weld deposition rates.

Controlled composition welding method

A method, an apparatus ( ), and a prefabricated replacement tube ( ) are provided for repairing a defect ( ) in a tube ( ), such as in a waterwall ( ). In the method, a replacement tube ( ) is prefabricated having a wall ( ), a central opening ( ) extending through a portion thereof, and a predetermined length. A length of the tube ( ), including the defect ( ), equal to the predetermined length is removed. The replacement tube ( ) is positioned between stubs ( ) of the tube ( ), and a rotatable torch ( ) of an automated welding apparatus ( ) inserted through the opening ( ) to align with a joint between an end ( ) of the replacement tube and a stub ( ). The torch ( ) is rotated to join it to the stub ( ) along the entire joint. The torch ( ) is then removed, turned 180 degrees, and reinserted to weld the remaining joint. Optionally, the replacement tube ( ) is held in position before welding by slip rings ( ) which are slid down to cover the joints.

Method and apparatus and prefabricated replacement tube for localized waterwall repair

A method for fabricating a valve includes hardened valve seats and a conventional valve stem which mates with the hardened valve seat. A valve seat support ring is attached to the body of the valve and to the hardened valve seat. HIP bonding is utilized to bond the hardened valve seat to the valve seat support ring. Conventional techniques, such as welding are used to attach the valve seat support ring to the body of the valve.

Growing community of inventors

Mooresville, NC, United States of America

William Frederick Newell, Jr