Effects of Countersink Hole on Driving Torques of Screw in Joints Constructed of Medium Density Fiberboard
Öz
Aim of study: The aim of this study was to investigate the effect of
countersink along with some other factors affecting screw driving torques in
joints made of medium density fiberboard (MDF). There is limited research has
been done in the field of screw driving torques in wood based composites. In
all of these studies, the specimen consisted of a single wood-based composite
material and metal plate which was used for the consistency of the screw
driving data. However, in this study, the screw driving torques were obtained
by the specimens consisted of two MDF testing blocks jointed by a screw.
Material and Method: In general, there were two main screw driving
torques; seating torque (SET) and stripping torque (STT). The MDF testing
blocks had dimension of 150 mm long × 75 mm wide and two different thicknesses
were used. For upper testing block, 8-mm-thick MDF and for lower testing block,
18-mm-thick MDF were used. Torques measurements were obtained by an adjustable
torque screwdriver. Factors were embedded screw orientation (face-to-face and face-to-side),
pilot-hole diameter (2.5 and 3.0 mm), pilot-hole depth (12 and 16 mm) and
countersink type (with and without countersink).
Main results: The results of statistical analysis indicated that the
four-way interaction among the embedded screw orientation, screw length,
countersink type and pilot-hole diameter was significant on the mean SET and
STT in the MDF joints.
Highlights: This study will help MDF manufacturers to understand the screw performance of their products in terms of screw driving torques.
Anahtar Kelimeler
Pilot-hole Diameter and Depth,Embedded Screw Orientation,Torque Wrench,Countersink Hole
Destekleyen Kurum
Proje Numarası
Teşekkür
Kaynakça
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