US 8,522,729 B2 · Contoured flat stud and stud arrangement for cyclone slag taps

Abstract

A stud and stud arrangement protects the water-cooled tubes of a slag tap outlet from corrosion and erosion by flowing slag and flue gas. The stud is a generally annular or ring-like segment. The stud has a projection terminating in an edge adapted to contact a tube at stud contact area, and has a weld surface for receiving a weld. The weld contacts a tube at a weld contact area and thermally and physically connects the stud to a tube. The weld surface area is greater than the stud contact area, thereby improving heat transfer between the tube and stud. The studs are disposed in an arrangement that is staggered in a direction perpendicular to the flow slag and flue gas.

Drawings

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Drawings

Claims9

Dependent claims

A stud arrangement for protecting water-cooled tubes of a slag opening adapted to deliver a flow of flue gas and slag, comprising a plurality of studs, each of the studs comprising:

an annular segment having first and second sides;
an outer edge connecting the sides;
and
a projection extending from the sides and terminating in an inner edge contoured to contact a tube and defining an inner edge depth, the projection having a surface adapted to receive a fillet weld between the inner edge and one of the sides and defining a weld depth;
wherein the weld depth is greater than the inner edge depth;
wherein the plurality of studs are disposed about the water-cooled tubes of the slag tap opening in a substantially horizontally-staggered arrangement;
wherein the studs are stacked in vertical columns, with each column vertically offset from the adjacent vertical column;
and
wherein the studs are offset in a direction perpendicular to a direction of the flow.

6 more elements

Dependencies are inferred from the claim text.

Description2,806 words

Summary1,680 words

#The subject invention pertains in general to cyclone furnaces for burning ash-containing fuels, and in particular to studs used to protect the water-cooled tubes forming the slag tap outlet.

#Cyclone furnaces were developed by The Babcock & Wilcox Company (B&W) in the 1940's. These cyclone furnaces have the ability to burn high-ash low-fusion temperature coals, which are particularly troublesome in pulverized coal boilers. FIG. 1 shows a cyclone furnace assembly 100, which comprises a generally horizontal barrel, typically 6 to 10 feet in diameter, attached to the side of a boiler furnace. The cyclone barrel is made up of water-cooled tubes 24, arranged in tangent-tube construction. Crushed coal is introduced through crushed coal inlet 32. Crushed coal and some air (primary 41 and tertiary 43) enter the cyclone through one or more specially designed burners on the front of the cyclone, such as radial burner 30.

#In the main cyclone barrel, a swirling motion is created by the tangential addition of secondary air in the upper cyclone barrel wall through secondary air velocity dampers 45. A unique combustion pattern and circulating gas flow structure result. The products of combustion eventually leave the cyclone furnace through a re-entrant throat 60, which includes water cooled tubes 22 adapted to form a slag tap opening or outlet 20. A molten slag layer develops and advantageously coats the inside surface of the cyclone barrel. The slag drains to the bottom of the cyclone and is discharged through slag tap 20.

Brief description of the drawings9 figures

#In the accompanying drawings, forming a part of this specification:

#FIG. 1 is a partial sectional perspective view of a cyclone furnace assembly where the present invention may be used;

#FIG. 2 is a partial sectional view of a known cyclone furnace stud and stud arrangement;

Detailed description938 words

#To further reduce erosion and corrosion in the slag tap region of a cyclone furnace, the present invention comprises an improved contoured stud design and an improved stud arrangement.

#An improved contoured stud 101 has been developed, as shown in FIG. 3B, which depicts two improved contoured studs 101 applied to a water-cooled tube 22. Similar to original contoured stud 1, improved contoured stud 101 has a generally arcuate shape, being designed as annular or ring-like segment. Improved contoured stud 101 preferably subtends an angle of about 30 to 45 degrees, i.e. so that a ring of about 12 to 8 studs would completely surround an associated tube 22.

#Also similar to original contoured stud 1, improved contoured stud 101 has an inner circumferential edge 102. Inner edge 102 is contoured to contact the associated water-cooled tube 22, with inner edge 102 having a diameter slightly greater than the outer diameter of tube 22. Outer edge 104 of improved contoured stud 101 connects upper side 106 to lower side 108 at right angles thereto and runs parallel to inner edge 102. Upper side 106 and lower side 108 are preferably flat and parallel to one another. Outer circumferential edge 104 is exposed to flowing slag and flue gas when in use.

Facts

Application

12/175,524Filed 18 Jul 2008

Published

US 2010/0012005 A121 Jan 2010

Granted

3 Sep 2013

Term ends

19 Mar 2031

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 974 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification11 codes

F23M 5/02
Casings; Linings; Walls: characterised by the shape of the bricks or blocks used
F23C 3/008
The chamber being arranged for cyclonic combustion: for pulverulent fuel
F23J 1/08
Removing ash, clinker, or slag from combustion chambers: liquid slag removal
F23M 5/04
Casings; Linings; Walls: supports for linings

Timeline

18 Jul 2008Application filedUS 12/175,524
28 Jan 2009Assigned to Credit Suisse, Cayman Islands Branch, AS Collateral Agentafter-acquired intellectual property security agreement (fifth supplemental filing)
23 Jul 2009Assigned to Babcock & Wilcox Power Generation Group, Inc.assignment of assignor's interest
23 Jul 2009Assigned to Babcock & Wilcox Power Generation Group, Inc.assignment of assignor's interest
21 Jan 2010PublishedUS 2010/0012005 A1
3 Aug 2010Assigned to The Babcock & Wilcox Company, Americon Equipment Services, Inc., Americon, Inc., Applied Synergistics, Inc., B & W Service Company, Babcock & Wilcox China Holdings, Inc., Babcock & Wilcox Construction Co., Inc., Babcock & Wilcox Denmark Holdings, Inc., Babcock & Wilcox Ebensburg Power, Inc., Babcock & Wilcox Equity Investments, Inc., Babcock & Wilcox International Sales and Service Corporation, Babcock & Wilcox International, Inc., Diamond Operating Co., Inc., Diamond Power Australia Holdings, Inc., Diamond Power China Holdings, Inc., Diamond Power Equity Investments, Inc., Diamond Power International, Inc., Palm Beach Resource Recovery Corporation, Power Systems Operations, Inc., Revloc Reclamation Service, Inc., National Ecology Company, North County Recycling, Inc.release of security interest
30 Sep 2010Assigned to Bank of America, N.A., AS Administrative Agentnotice of grant of security interest in patents
3 Sep 2013GrantedUS 8,522,729 B2
22 Jul 2014Assigned to Bank of America, N.A., AS Administrative Agentsecurity interest
28 Jul 2015Assigned to Bank of America, N.A., AS Administrative Agentsecurity interest
24 Sep 2015Assigned to The Babcock & Wilcox Companychange of name
10 Aug 2017Assigned to Lightship Capital LLCsecurity interest
17 May 2018Assigned to Babcock & Wilcox Enterprises, Inc., The Babcock & Wilcox Company, Diamond Power International, LLC, Babcock & Wilcox Megtec, LLC, Megtec Turbosonic Technologies, Inc., Babcock & Wilcox Universal, Inc., Babcock & Wilcox Technology, LLCrelease of security interest
26 Feb 2021Assigned to Pension Benefit Guaranty Corporationsecurity interest
1 Jul 2021Assigned to Diamond Power International, LLC (F/K/A Diamond Power International, Inc.), Megtec Turbosonic Technologies, Inc., The Babcock & Wilcox Company (F/K/A Babcock & Wilcox Power Generation Group, Inc.), Babcock & Wilcox Spig, Inc., Babcock & Wilcox Technology, LLC (F/K/A Mcdermott Technology, Inc.), Sofco-Efs Holdings LLC, Babcock & Wilcox Megtec, LLCrelease of security interest
22 Jul 2021Assigned to Msd Pcof Partners Xlv, LLC, AS Agentsecurity interest
19 Dec 2023Assigned to The Babcock & Wilcox Companyrelease of security interest
19 Jan 2024Assigned to Axos Bank, AS Administrative Agentsecurity interest
13 Sep 2024Assigned to The Babcock & Wilcox Company, Diamond Power International, LLC, Americon LLCrelease of security interest
3 Mar 2025Assigned to Pension Benefit Guaranty Corporationsecurity interest
18 Jul 2025Assigned to B. Riley Financial, Inc.security interest
12 Oct 2026TodayWithin its term
19 Mar 2031Term endsEstimated, includes 974 days of adjustment

Contoured flat stud and stud arrangement for cyclone slag taps

Life of this patent

Contoured flat stud and stud arrangement for cyclone slag taps

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims9

Description2,806 words

Drawings

Classification11 codes

Life of this patent

Description2,806 words