Measures and yields of products and residues 



3311 



Yield of pallet cants and lumber. — Craft and Emanuel (1981) processed 

 hardwood sawbolts taken from poletimber thinnings from 36 sample plots of 

 various timber types in West Virginia. They found that woods-run 4- and 6-foot 

 long bolts from these thinnings were well suited for commercial pallet produc- 

 tion. Bolts containing unsound heart defects and those containing sweep exceed- 

 ing 1.5 inches should be eliminated. Resulting bolts (6- to 10-inches in scaling 

 diameter) need not be segregated and should yield about 55 percent of cubic-foot 

 volume in acceptable pallet cants and boards. When only 4- by 4- and 4- by 6- 

 inch cants are produced (no side lumber), product yield is approximately 45 

 percent of the cubic foot volume. The quality of cants from such woods-run bolts 

 is adequate for production of permanent or returnable warehouse pallets. Less 

 than 3 percent of pallet parts produced were unusable. 



Average yield per bolt, all species combined, of cants and side lumber varied 

 with bolt diameter and length, as follows: 



Diameter 

 class 4-foot bolts 6-foot bolts 



Inches Board feet — - 



6 5.3 8.1 



7 6.4 9.6 



8 9.0 14.4 



9 11.8 18.0 

 10 14.9 22.7 



In this study, only 4-inch and wider lumber was tallied as usable; all 5-inch 

 lumber was tallied as 4-inch widths, and all side lumber over 6 inches as 6-inch 

 widths. 



Average yield of pallet cants and side lumber decreased with increased sweep, 

 as follows: 



Sweep 

 class 



Inches 



0-0.5 



0.6-1.0 



1.1-1.5 



Some processes recover only pallet cants from boltwood (no side lumber); 

 yield of pallet cants only from the sample bolts also varied with sweep class, as 

 follows: 



Sweep 

 class 



Inches 



0-0.5 



0.6-1.0 



1.1-1.5 



Table 27- 122 A shows the effect of sweep on pallet stock by bolt diameter 

 class. 



Material flow (yield) diagrams for eight other projected pallet operations are 

 shown in figures 28-2, 28-13, 28-19, 28-21, 28-24, 28-26, 28-30, and 28-36. 



