Barkless Logs For Sawmill

Log is ahecrred ol bcrrk by two oscillcriing iets- ol wcrter, which becm 1301 pounds ol pressure per squqre iach cacinst btrrk. Big lrunnion wheels leed log lorwcrd over iets cnd rotqte it at the gcme time..

Longview-, Washington-Since pioneer axes first felled America's sawtimber, bark-covered logs have comprised the diet of lumber-making mills. This "skin", ranging up to many inches in thickness, frequently becomes a sawing and waste disposal problem to the millmen. From a utilization standpoint, there has been little financial incentive to recover the bark for commercial processing'

Bark-free sawlogs are now the new look at Weyerhaeuser Timber Company's integrated operations at Longview, \A/ashington, where lumber is only one of the many products made from logs. llere, 'rT'here millir-rg leftovers become raw material for several manufacturing processes' a certain percentage of Douglas fir bark from a plyrvood plant already is finding its rvay into commercially marketed Silvacon products. The new "slick" look in salvlogs is achieved in one minute with tu'o oscillating high pressure jets of water, action units of a specially designed hydraulic barker.

The first installation of its kind in the Douglas fir region of Oregon and Washington, the barker was constructed as another link in the company's chain of wood:using processes which are harnessing a greater percentage of rarn' log contents for corisumer use. The unit was engineered to produce clean wood recovered from Douglas fir sawmill slabs and edgings, which is to. be chipped as ral\r material for a sulphate pulp mill schedriled to begin production this fall.

Hydrcrulic scwlog barler ie ingialled over chcrin hcul which eupplies -itl *ittt logs. frcrul is ct lelt, bcrrker crt right. Biq trunnion wbeels Ieed logr ovel iwo oacillcrling iets, sprcrY lrom whicb qppeqrs in center cI photo.

The barker, straddling the elevated log haul into the mill, consists of a covered'building whose upper portion houses the transfer chains and trunnion wheels that by-pass the big logs over the gscillating:jets and returh them to the log chain feeding the sarvmill's big bandsarv. The lower portion contains the pumping machinery which surges lvater, under 1300 pounds of pressure per square inch, against the log's bark.

The barker" was designed by Weyerhaeuser's Engineering Depart.ment in Tacoma, under the direction of J. S. Abel. with the collaboration of M. L. Edwards ,who helped (Continued on Page 12)