PENGARUH SKEDUL PENGERINGAN DAN VARIASI KERAPATAN INCISING TERHADAP KARAKTERISTIK PENGERINGAN KAYU MAHONI (Swietenia macrophylla King)

HYANA SWARGANI, Tomy Listyanto, S.Hut, M.Env.Sc.,Ph.D.

2017 | Skripsi | S1 KEHUTANAN

Pengeringan kayu seringkali membutuhkan waktu, energi, dan biaya yang tinggi. Salah satu cara untuk mempercepat waktu pengeringan adalah dengan incising dan pengeringan suhu tinggi. Pengeringan kayu penting dilakukan untuk meningkatkan kualitas kayu. Penelitian ini bertujuan untuk mengetahui pengaruh interaksi skedul suhu pengeringan dan kerapatan incising pada laju pengeringan dan cacat pengeringan serta untuk mengetahui pengaruh kerapatan incising pada sifat mekanika kayu mahoni yang telah dikeringkan. Pohon mahoni dengan diameter 30-43 cm yang berumur 25 tahun digunakan pada penelitian ini. Rancangan acak lengkap dengan 2 faktor yaitu skedul suhu pengeringan dan kerapatan incising. Skedul suhu pengeringan meliputi skedul suhu tinggi dan skedul kayu mahoni suhu awal 60 derajat C, depresiasi bola basah 4 derajat C dan suhu akhir pengeringan 90 derajat C. Lima jenis kerapatan meliputi 0,1000,2000,3000,dan 4000 lubang/m2. Lubang incising berdiameter 3 mm. Sampel pengeringan dikeringkan hingga kadar air 12%. Parameter yang diamati meliputi laju pengeringan, retak permukaan, retak ujung, dan retak dalam. Uji keteguhan lengkung statik dilakukan berdasarkan standar British 373. Data yang dihasilkan kemudian diuji analisis varian (ANOVA) dengan taraf uji 5% serta uji lanjut Honestly Significant Difference Tukey. Hasil penelitian menunjukkan bahwa variasi kerapatan incising berpengaruh nyata terhadap laju pengeringan. Laju pengeringan terbesar terdapat pada kerapatan incising 4000 lubang/m2 sebesar 11,70% per hari. Faktor skedul suhu dan kerapatan berpengaruh nyata terhadap retak permukaan dan retak ujung, namun tidak berpengaruh signifikan terhadap retak dalam. Sifat mkanika kayu mahoni tidak terpengaruh oleh variasi kerapatan incising pada penelitian ini

Wood drying occasionally require time, energy, and high cost. One of the efforts to increase drying rate is incising and high temperature drying. Wood drying is important to improve wood quality. The research aims to investigate the effect of the interaction between drying schedule and the density of incising on drying rate and defects, and to examine the effect of incising density on the mechanical properties of the dried mahogany wood. Mahogany trees with diameter of 30-43 cm age 25 were used. Completely Randomized Design with two factors, which were drying schedule and density of incising were applied. Drying schedule were high temperature schedule and mahogany schedule with initial temperature 60 degree C, wet bulb depression of 4 degree C, and the final temperature of 90 degree C. Five incising density were 0, 1000, 2000, 3000, and 4000 holes/m2. The diameter of incising hole was 3 mm. The drying samples were dried until reach final moisture content of 12%. Drying rate, surface checks, end checks, and honeycomb were observed to examine the drying characteristic. Static bending test was also conducted in a accordance to British Standard 373. Data was examined by variance analysis (ANOVA) in 5% of significant level and followed by Honestly Significant Difference Tukey test. The result showed that the variations of incising density influence significantly on the drying rate. The largest drying rate occurred in the incising density of 4000 holes/m2 which was 11.70% per day. Factors of drying schedule and the variations of incising density influence significantly on surface checks and end checks but not significantly on honeycomb. Static bending was not influenced by the variation of incising density in this research.

Kata Kunci : skedul pengeringan, suhu tinggi, mahoni, kerapatan incising;drying schedule, high temperature, mahogany, incising density