GROUND-WOOD PULP. 29 
POWER CONSUMPTION PER UNIT OF STRENGTH. 
It has always been known that the consumption of a great amount 
of power will produce pulp of a greater strength. The relative 
effect, however, in using different amounts of power is probably best 
shown in figure 21. The strength as represented by Mullen or 
Schopper tests increases with increasing power consumption per ton. 
Figure 22, curve A, shows the relation between horsepower con- 
sumption per ton of pulp per meter of breaking length of paper made 
Hue (ei gael cmame ene Mae 
| 125———— 60 
: PoC EC a 
136-——— So Vs 
: fee Cen ai na, 
' pry) 
2 
oll 
150— ¢ 50] 
= 38 
ge 
a 
ee 
167——q 45 
a 
© 
Lad 
Ge 
=) 
B 
188-——— yu 40 
Be 
250——— 30 
27 | (28) 11297 1030 all 1.320199 a4 4.95.) 36.37 
STRENGTH FACTOR—MULLEN TEST IN POINTS PER POUND 
Fig. 19.—Relation of strength of paper to pressure and speed. (Spruce runs 32 to 38, inclusive.) 
_ trom it, and the power consumption in grinding a ton of the pulp. 
_ At low values of power consumption greater strength is produced 
4 per horsepower than at high values. The horsepower per ton per 
point per pound is also shown in the same figure, curve B. 
STEAMED WOOD PULP AND ITS USES. 
‘The pulp made by grinding steamed wood can be used for different 
purposes, depending largely. upon the nature of the grinding process. 
If a sharp and coarse stone is used a large number of shives will be 
present and the pulp will serve for the manufacture of box board or 
