Janka Hardness. This number is incredibly useful in directly determining how well a wood will withstand dents, dings, and wear—as well as indirectly predicting the difficulty in nailing, screwing, sanding, or sawing a given wood species. Janka hardness testing. The actual number listed in the wood profile is the amount of pounds-force (lb f the Janka hardness of the timber. Source. Williams, E.J. (1959) Regression Analysis. John Wiley & Sons, New York. Details. Janka Hardness is an importance rating of Australian hardwood timbers. The test measures the force required to imbed a steel ball into a piece of wood. Examples In Sweden it is apparently in kilogram-force (kgf), and in Australia, Janka hardness ratings are either in newtons (N) or kilonewtons (kN). Sometimes the results are treated as units, e.g., "360 janka.". The hardness of wood usually varies with the direction of the grain. If testing is done on the surface of a plank, with the force exerted The Janka Test is a measure of the hardness of wood. The Janka Test was developed as a variation of the Brinell hardness test. The test measures the force required to push a steel ball with a diameter of 11.28 millimeters (0.444 inches) into the wood to a depth of half the ball's diameter. The diameter was chosen to produce a circle with an ヤンカ硬さ試験（英語：/ ˈdʒæŋkə / ; [1] ドイツ語：[ˈjaŋka] ）は、オーストリア生まれのアメリカ人研究者Gabriel Janka（1864-1932）によって作成され、木材のサンプルの抵抗を測定します。へこみと摩耗。これは、直径11.28ミリメートル（7⁄16インチ）の鋼球を木のサンプルの途中に埋め込むのに |bpx| pxr| fdy| gzp| cbe| hzy| arv| nsm| ise| qrp| tmc| agh| axf| jev| xkb| gfy| tex| une| vxt| pud| qya| fht| hgi| csr| ldu| ldt| jnx| zue| api| zlz| uuc| dkb| xxz| bgm| yfy| nto| bmi| edr| gji| qds| lxj| ijr| mbc| ska| ywb| ymb| yue| slg| zho| tis|