牧草類の圧縮小塊化に関する研究 (第3報)

ウエーハの耐久性と各種強度

抄録

1. Fall tests: Various compressed wafers were dropped on a steel plate from 1.5 meter height next day or on the 50th day after extruding, and the following results were obtained concerning the collapse of those wafers.
(1) If the forming size is equal, the durability of wafer increased with increase of final dry matter density ρd and also with increase of moisture content at hay forming if ρd was the same.
(2) The orchardgrass wafer was more durable than the ladinoclover wafer. The former was difficult for feeding and packing because its fiber was stiff, thick and long, and collapsed mainly by extruding, whereas the latter often contained little leaves and broke mainly by cracks.
(3) The large, wet, heavy wafer was not durable for the reason of its large shock energy.
(4) Chopped hay wafers were not practical because their durability, when compared with that of original hay wafers, decreased considerably with decrease of fiber length.
(5) The durability of cross cut wafers of ladinoclover with large ρd was almost equivalent to that of original wafers, but that of orchardgrass with stiff, thick and long fiber was slightly reduced from that of original one.
(6) From many view points, the wafer of medium moisture content and small ρd (=0.8), and also of large diameter and short height was desirable for durability.
(7) It was considered that the fall test was a desirable method to indicate the durability of wafer because the conditions of fall test resembled that of pactical handling of wafers.
2. Vertical and horizontal one-axle compression test:
(1) At the vertical compression test, resistance-displacement diagrams showed four forms. The resistance, generally, arrived at the collapse strength of fiber, after passing through the compressive shearing fracture point as a wafer block. At the horizontal compression test, the fracture point as a wafer block was not clear.
(2) The fiber was broken to pieces at the collapse strength point, and this strength value under medium moisture content was larger than that of compressive shearing fracture of wafer block.
(3) The ρd of wafer had little influence upon the compression strength, which were higher as the moisture content was lower, and these characteristics were contrary to that of fall tests, therefore, the compression test was not desirable as an indication method of durability of wafer.
3. Cutting resistance: The cutting resistance value on the cross-section of wafer was very small and hardly influenced by any conditions of hay or cutters, therefore, the continuous compressing and cutting method was considered to be useful.