TIIK KUAETZER TKEPARATOR WITH DOOR OI'EN, SUc>\\I.\<; TUIX'K LOAIl OF I.l'MIiER WITHIN 



Evolution in Lumber Seasoning 



Previous articles have appeared in Hardwood Becord during 

 the last two years telling of the success that has attended the 

 far from new, but thoroughly efficient steaming-wood-under-pres- 

 sure system to prepare lumber taken directly from the saw for 

 prompt seasoning. This has been rendered possible In- the pat- 

 ented apparatus manufactured and sold by The Kraetzer Company 

 of Chicago, and built for it by the AUis-Chalmers Company, Mil- 

 waukee, Wis. 



The claims of the manufacturer of the apparatus are that its 

 use renders the lumber treated susceptible of being thoroughly 

 air-dried in the open in less than, one-half the time ordinarily 

 required for air-drying, or that it can be kiln-dried in an ordinary 

 kiln in much less than one-half the time usually necessary to thor- 

 oughly dry air-dried stock; that it prevents staining and case- 

 hardening, and minimizes checking, end-splitting and other sea- 

 soning defects; that it renders the color of the lumber more uni- 

 form, and materially improves its milling qualities; that lumber 

 treated through this apparatus will dry absolutely straight, and 

 to materially less weight than air-dried stock; and that shrinkage 

 is materially reduced, often to less than fifty per cent of ordinarily 

 treated air or kiln-dried lumber. 



One picture used in connection with this article shows the 

 apparatus together with its steam fittings; a second one is a 

 general view of the equipment and storage tracks recently in- 

 stalled by the Eennett Hardwood Lumber Company at its Mem- 

 phis, Tenn., plant; a third picture shows a view of the equipment, 

 with a truck-load of lumber on the transfer track ready to be 

 shoved into the cylinder; and a fourth picture a left-hand and 

 nearer view of the steaming cylinder and a truck-load of lumber. 



This commercialized apparatus has been employed for several 

 years by the John Schroeder Lumber Company at Milwaukee, 

 Wis.; for some months past by Busse & Burgess, Inc., Memphis, 

 Tenn., and by the Santee River Cypress Lumber Company at 



Ferguson, S. C, and recent installations have been made at the 

 oak sawmill and flooring plant of the Forman-Earle Company at 

 Heidelberg, Ky., and at the big gum and oak sawmill institution 

 of the Lamb-Fish Lumber Company at Charleston, Miss. Several 

 other equipments have been sold to various other institutions 

 during the last few weeks. 



The complete system involves an abandonment of the lumber 

 yard per xe, and in its stead storage tracks are employed, on 

 which are wheeled the truck loads of lumber, which dry out in 

 shipping condition in from fifteen to thirty days after steaming. 

 To obtain the highest efiiciency, the trucks are loaded at the sort- 

 ing chains, and then shoved out on a transfer track to the pre- 

 parator; steamed under moderate pressure for from five to thirty 

 minutes, depending on the kind of lumber and its thickness; 

 removed from the cylinder, and shoved out onto storage tracks, 

 from the farther end of which the dry stock is loaded directly 

 into cars. 



The manufacturers of this apparatus estimate that from the 

 fact that lumber manufacturers by the use of this equipment 

 can do the same volume of business on less than one-half their 

 present iu vestment in stock; that the economy in labor cost is 

 material; that the saving in degrade is no inconsiderable factor; 

 that there is a material economy in interest, taxes and insurance; 

 rliat the process materially lightens the weight and decreases the 

 shrirkage of lumber, and that altogether there is a total saving, 

 between the sawmill and the car, of between three and four 

 dollars a thousand feet. If this proves true, and there is no 

 good reason to doubt the accuracy of the estimate, the system 

 means not only a revolution of lumber drying methods, but a gain 

 in practical efficiency in lumber production that spells more for 

 economy than even the band-saw does over the circular. 



One of these apparatus is capable of handling up to one hun- 

 dred thousand feet output daily. As an average three charges 



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