“鋸－乾－剖”加工方法對降低3.5mm木荷板材翹曲之功效

The Efficiency of Saw-Dry-Rip Process on Reducing Warp of 3.5cm Schima superba

翟思湧(Sy-Yung Jai) ； 黃清吟(Ching-Yin Hwang) ； 李銘鐘(Ming-Chung Lee)

《林業試驗所研究報告季刊》 3卷4期 (1988/12) Pp. 195-207

https://doi.org/10.7075/BTFRI.198812.0195

摘要

爲探討“鋸－乾－剖”加工方法(Saw-Dry-Rip Process, SDR)是否可有效降低木荷製品之翹曲程度，藉以提高其利用價值，特以台灣中部産木荷爲試驗材進行試驗。試材規格爲3.5×9×120cm及3.5×6×120cm兩種。試驗處理有四：(1)CC=傳統製材，傳統窯乾；(2)CH=傳統製材，高溫窯乾；(3)SC=連續製材，傳統窯乾；(4)SH=連續製材，傳統窯乾。
研究結果顯示：SDR加工方法，不論採行高溫或傳統窯乾，均有降低翹曲之功效。但因高溫乾燥易招致嚴重的蜂巢裂、潰陷或乾裂等缺點，影響木材使用。故對木荷言，以採行傳統窯乾爲宜。SC及CH之乾製品材積收率比CC及CH平均低約13%；但其翹曲程度小於6.5mm之材積收率卻較CC及CH平均高約80%。故連續製材可提高木材之利用率。

關鍵字

“鋸－乾－剖”加工方法 ； 連續製材 ； 高溫乾燥 ； 木荷

並列摘要

The objective of this research was to evaluate the efficiency of SDR process in reducing warp of 3.5cm Schima superba lumber. Five sample logs, 120cm in length, 53.4cm (average)in diameter, cut from middle Taiwan, were used for this study. The study design was a 2 by 2 factorial using two sawing methods (conventional-sawing and live-sawing) and two drying methods (conventional-drying and high-temperature drying).Treatment combinations were:
(A)CC=Conventional sawing/conventional drying (control).
(B)CH=Conventional sawing/high-temperature drying.
(C)SC=SDR live sawing/conventional drying.
(D)SH=SDR live sawing/high-temperature drying.
The final two cut size of the test boards were 3.5×9×120 and 3.5×16×120cm.
The data show that for Schima superba:
1. Each treatment (SC,SH,CH) results in reduced warp compared to the control (CC) treatment.
2. Live-sawing, whether with conventional or high-temperature drying, produces straighter and flater boards than conventional-sawing.
3. High-temperature drying reduces quite a lot of drying time and energy consumption; but incurs severe drying defects, specially in honeycomb and collapse. It is evident that high-temperature drying is not suitable for Schima superba.
4.The volume yield for live sawn material was slightly lower (about13% in average) than those of conventional sawn, however, the recovery of the material under 6.5mm in warp for the former method was much higher (about 80% in average) than those of later method. It a appeared to indicate that SDR process can increase the yield of acceptable piecess.
5. The relationship between M.C. and shrinkage in all of the treatments was in a curvilinear correlation.

並列關鍵字

SDR process ； live-sawing ； high-temperature kiln drying ； Schima superba