The Babcock & Wilcox Company

Other

Babcock & Wilcox Power Generation Group, Inc.

Mcdermott Technology, Inc.

James M Tanzosh

Douglas D Zeigler

Walter R Mohn

George H Harth, Iii

Mark J Topolski

John Hainsworth

George B Watson

Dale F LaCount

Michael N Gold

Steven C Kung

Russell A Stanley

Kenneth L Santelmann

Roger A Clocker

Donald C Housley

William C Mack

Avelino G Bolumen

Thomas L Garabedian

A method of providing boiler tubes with a variably ribbed interior surface. A suitably dimensioned spindle with a channel having a desired pattern on the exterior surface of the spindle is wrapped by a wire-like member in the channel so as to form thereon a reverse image of the desired, patterned tube ribbing. A brazing metal paste is applied on the exterior surface of the wire-like member and the spindle is inserted into a tube to be ribbed. The wire-like member is released from the spindle to allow the wire-like member to conform to the inner surface of the tube, and the tube is heated to the melting temperature of the brazing metal paste so that the wire-like member bonds to the inner surface of the tube, and the metal tube is then cooled.

Method of forming, inserting and permanently bonding ribs in boiler tubes

A method for producing chromium carbide coatings on steel provides a steel component having a surface which is carburized to contain at least about 0.40% by weight carbon and is followed by chromizing the surface to form a chromium carbide coating on the surface.

Method for producing chromium carbide coatings

An improved process for chromizing and chrome-siliconizing 400-series stainless steel components, and in particular, 430 stainless steel components, such as boiler panel studs. The process includes the addition of between 0.12%-0.25% by weight of calcium fluoride salt to the conventional 4% by weight of ammonium chloride activator salt to the coating composition used in known diffusion coating processes. In a more preferred embodiment, small amounts of silicon powder, such as between about 0.12%-0.25% by weight, are added to the two salts and the diffusion coating material. A coating composition is provided as well.

Process and composition for chromizing 400-series stainless steels

An improved process for chromizing commercial quantities of small, industrial, ferrous-based parts, such as but not limited to threaded connectors, pins, bolts, nuts, washers, fasteners, fittings, couplings, studs, etc., uses a retort filled with layers of parts coated with a chromium-containing slurry. The plurality of parts are arranged in layers on sheets of refractory felt paper and are heat treated simultaneously for causing the chromizing reaction between the slurry and the ferrous-based parts.

Method for chromizing small parts

A shield that is normally positioned or wrapped around a boiler tube when such tube is exposed to extreme operating conditions. This shield consists of an elongated strip of thin material that is formed as a helix. This strip also incorporates a means for spacing this strip from the tube so as to create a gap between the tube and the shield. Generally the shield is secured to the tube by spot or button welding only the longitudinal end regions of the strip to the tube. By thus wrapping and securing one or more such shields to the tube, the tube is protected while still permitting both it and the shield(s) to expand and contract as needed.

Continuously slitted roll-on tube shield

A method for coating a substrate with a corrosion resistant surface comprises the steps of coating a portion of the substrate with a nickel (II) nitrate hexahydrate solution. The solution-coated substrate is then heated to a temperature greater than 303.degree. C. until a nickel oxide coating remains.

Corrosion resistant nickel oxide surface coating

The surface hardening diffusion process for an austenitic material such as 300-series stainless steel uses a pack carburization process at a temperature range from about 1500.degree. F. to about 2500.degree. F. for a period of time ranging from about one (1) to about eight (8) hours. Chromium carbides are formed on the surface of the austenitic material for increasing its wear resistance.

Surface hardened 300 series stainless steel

A reversible, wear-resistant ash screw cooler section is provided with a carbon steel inner liner having a high chrome, high carbide overlay emplaced thereon to improve its wear and erosion resistance. To facilitate obtaining the maximum wear out of the section, the replaceable section is made symmetrical about its vertical and longitudinal centerline and provided with suitable compatible flanges and symmetrically placed cooling water hookups on the ends of the section to allow the section to be reversed, end for end, and reconnected to the ash screw cooler.

Reversible, wear-resistant ash screw cooler section

A method and apparatus for sealing the gap between adjacent boiler tubes of a panel wall thereby making the panel wall air-tight. First and second sealing members are secured to opposite sides of adjacent boiler tubes thereby defining a gap therebetween. This gap is then filled with a metal salt solution which is dried in place so as to leave a residue behind. Subsequently, this residue is further heated which converts it to a metal oxide that forms an air-tight ceramic plug. This plug possesses properties which make it resistant to deterioration once the panel wall goes into service.

Growing community of inventors

Silver Lake, OH, United States of America

James M Tanzosh