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US6672256: Preformed modular trefoil and installation method


Filing Information

Inventor(s) Ronald J. Marr · Larry E. Shultz ·
Assignee(s) J. E. Baker Company ·
Attorney/Agent(s) Woodcock Washburn LLP ·
Primary Examiner Jiping Lu ·
Application Number US9873514
Filing date 06/05/2001
Issue date 01/06/2004
Prior Publication Data
Predicted expiration date 02/08/2020
U.S. Classifications 122/103  · 122/119  · 122/118  ·
International Classifications --
Kind CodeB2
International Classifications 432103 · 432105 · 432108 · 432110 · 432111 · 432118 · 432119 ·
Related U.S. Application DataThis Application is a continuation of U.S. provisional Application Ser. No. 09/499,788 filed Feb. 8, 2000 now U.S. Pat. No. 6,257,878 (Bker-0004).
7 Claims, 8 Drawings


A trefoil for a rotary kiln is provided that has at least three spoke-like refractory legs. Each one of the legs extends radially outwardly from a center of the trefoil; spans approximately from the kiln shell to the center of the kiln; is pre-formed outside of the kiln for installation as a single-leg unit; and has a mating surface that preferably is uniform and even, thereby lacking interlocking features. The mating surfaces of the legs abut one another at the kiln center to provide mutual support. An alignment member, such as a pair of longitudinal angles, are welded to the kiln shell to position the legs. A corresponding method of installing the trefoil is disclosed that includes positioning and shimming the first two legs at the 4 oclock position and 8 oclock position, and installing the third leg at the 12 oclock position.

Independent Claims | See all claims (7)

  1. 1. A heat exchanger for use within a rotary kiln that includes a cylindrical steel shell with an internal refractory lining, said heat exchanger comprising a first, preformed configuration and a second, installed configuration, said heat exchanger, in the first, preformed configuration, comprising at least three loose, refractory legs, each one of the legs comprising: a foot, a mating end opposing the foot, and a body extending between the foot and the mating end, each one of the legs is continuous and between the foot and the mating surface, thereby forming a single-leg unit, and said heat exchanger, in the second, installed configuration that is formed within the kiln from the loose legs, having each one of the continuous, single-leg units assembled into a spoke-like configuration wherein each one of the legs extends substantially radially outwardly from a center thereof to proximate the shell, and metallic retainers coupling the mating ends of the leg to the shell.

References Cited

U.S. Patent Documents

Document NumberAssigneesInventorsIssue/Pub Date
US1431530 LEICESTER CHARLES H Leicester Oct 1922
US1534475 AMERICAN ARCH CO Willett et al. Apr 1925
US1741680 DAVEY GEORGE W Davey Dec 1929
US1920677 BURKE RICHARD W Burke Aug 1933
US2341971 AMERICAN ARCH CO Antill Feb 1944
US2889143 REANEY WARFORD A Reaney et al. Jun 1959
US3030091 HARBISON WALKER REFRACTORIES Wicken et al. Apr 1962
US3036822 SMIDTH & CO AS F L Andersen Apr 1962
US3169016 HARBISON WALKER REFRACTORIES Wicken et al. Feb 1965
US3175815 HARBISON WALKER REFRACTORIES Wicken et al. Mar 1965
US3201100 CIMENTS DU NORD Dussossoy Aug 1965
US3221614 JOHANNES PERTIEN Pertien Dec 1965
US3227430 KAISER ALUMINIUM CHEM CORP Vaughan, Jr. Jan 1966
US3346248 KAISER ALUMINIUM CHEM CORP Martinet et al. Oct 1967
US3362698 DETRICK M H CO Cerny et al. Jan 1968
US3521867 ITALCEMENTI SPA Bucchi Jul 1970
US3834108 LUDVIGSEN H Ludvigsen Sep 1974
US4340360 Veitscher Magnesitwerke-Aktiengesellschaft Hoedl et al. Jul 1982
US4475886 Kaiser Aluminum & Chemical Corporation Tyler Oct 1984
US4543893 Didier-Werke AG Künnecke Oct 1985
US4846677 Dresser Industries, Inc. Crivelli et al. Jul 1989
US4960058 Merkle Engineers, Inc. Materna Oct 1990
US4975049 General Refractories Company Roenigk et al. Dec 1990
US5330351 RRI, Inc. Ransom, Jr. et al. Jul 1994

Foreign Patent Documents

Document NumberAssigneesInventorsIssue/Pub Date
FR721910Mar 1932
GB906595SMIDTH & CO AS F LMay 1962

Other Publications

Lime, “Castable trefoils in rotary lime kilns,”

Referenced By

Document NumberAssigneeInventorsIssue/Pub Date
USRE44612 --