Development of Drying Schedule of Superior and Conventional Teak Wood of Ten Years-old Planted in Blora, Central Java
Authors: Listyanto Tomy , Darmawan Yusuf Setia , Pujiarti Rini , Hidayati Fanny , Lukmandaru Ganis , Sulistyo Joko 
Published: November 2016

The aims of this study were to investigate drying defect characteristics, to develop proper drying schedule, and to analyze the relationship between the developed drying schedule and its wood properties. This study used superior and conventional teak wood of ten years-old planted in Blora, Central Java. Sample from different axial positions (bottom and middle part) and different board thicknesses (20 mm and 40 mm) were taken. Drying schedule was developed in accordance to Terazawa method, which dried the sample for 72 h at a temperature of 100 °C. Initial moisture content, crack, collapse, and honeycombing were observed to determine the proper drying schedule. The developed drying schedule then was related to their characteristics, such origin of the seedling, thickness, density, and heartwood percentage. The proper scheduled was also applied in larger sample and evaluated. The results showed that there were five variations of drying schedule for superior and conventional teak wood. Chi square analysis indicated that the board thickness affect significantly on developing drying schedules. Boards with a thickness of 20 mm can be dried with an initial temperature of 70 °C, the wet bulb depression 7°C, and the final temperature of 105°C. Further, boards with a thickness of 40 mm should be dried with a softer drying schedule with an initial temperature of 60°C, wet bulb depression temperature of 4 °C, and the final temperature of 85°C. Application of the selected drying schedule was succeed without any significant defects.Keywords: superior; teak; drying schedules; inferior; wood Pengembangan Skedul Pengeringan Kayu Jati "Mega" dan Konvensional Umur 10 tahun Ditanam di Blora, Jawa tengahAbstractTujuan dari penelitian ini adalah mengetahui karakteristik cacat pengeringan, skedul pengeringan yang sesuai, variasi ketebalan papan serta beberapa sifat kayunya terhadap skedul pengeringan. Penelitian ini menggunakan kayu jati prospektif unggul dan konvensional umur 10 tahun dari Blora, Jawa Tengah dengan letak aksial yang berbeda (pangkal dan tengah) serta ketebalan papan masing-masing 20 mm dan 40 mm. Penyusunan skedul pengeringan menurut metode Terazawa, dengan pengeringan selama 72 jam pada suhu 100°C. Parameter yang diamati yaitu kadar air awal, cacat retak, kolaps, dan honeycombing. Cacat yang terjadi digunakan untuk penyusunan skedul pengeringan. Skedul pengeringan selanjutnya diuji hubungannya dengan sumber asal bibit, ketebalan, berat jenis, dan persen kayu terasnya. Skedul pengeringan yang paling sesuai selanjutnya diujicoba dan dievaluasi. Berdasarkan hasil penelitian, diajukan lima skedul pengeringan. Hasil analisis chi square menunjukkan bahwa ketebalan papan memiliki hubungan signifikan terhadap variasi skedul pengeringan. Papan dengan ketebalan 2 cm dapat dikeringkan dengan suhu awal 70°C, depresiasi bola basah 7°C, dan suhu akhir 105°C. Selanjutnya, papan dengan ketebalan 4 cm perlu dikeringkan dengan skedul yang lebih lunak dengan suhu awal 60°C, depresiasi suhu bola basah 4°C, dan suhu akhir 85°C. Hasil uji aplikasi menunjukkan hasil yang memuaskan dengan cacat yang tidak signifikan.