HÜSEYİN YÖRÜR, ÖNDER TOR, MUHAMMED NURİ GÜNAY, Emre BIRINCI

Kontrplakta farklı değişkenlerin vida çekme direnci üzerindeki etkisi

ÖzetÇalışmanın amacı: Kontrplağın vida çekme direnci üzerine kılavuz deliğinin, vida tipinin, vidalama yönünün, suda bekletmenin ve yapıştırıcının etkisini araştırmaktır.Materyal ve Yöntem: Çalışmada çapları sırasıyla 3.5 mm ve 4 mm olmak üzere 2 tip vida kullanılmıştır. Temin edilen 18 mm kalınlığındaki kontrplak TS EN 13446 standardına göre 50 mm x 50 mm boyutlarında ebatlandırılmıştır. Kılavuz deliğinin çapı, testlerde kullanılan vida çapının %80’i olacak şekilde delme işlemi yapıldı. Polivinil asetat (PVAc) ve Poliüretan (PÜ) tutkalları kılavuz deliklerine enjekte edildikten sonra örnek yüzeyine ve kenarına vidalama işlemi gerçekleştirildi. Örneklerin yarısı 2 saat süre ile suda bekletildikten sonra vida çekme testleri yapıldı. Testlerin sonuçları istatistik analiz ile yorumlandı.Sonuçlar: Sonuçlar incelendiğinde kılavuz deliği açılmayan örnekler daha yüksek vida çekme direnci göstermiştir. Ayrıca yüzeyden uygulanan vida çekme direncinin kenardan uygulanana göre daha yüksek olduğu tespit edilmiştir. Tutkal uygulanan kılavuz delikli örnekler incelendiğinde Poliüretan (PÜ) uygulananların vida çekme mukavemeti Polivinil asetat (PVAc) uygulananlara göre daha yüksek olduğu belirlenmiştir. Suda bekletilmiş örnekler incelendiğinde daha düşük vida çekme mukavemeti göstermiştir. Ayrıca vida çapı arttıkça vida çekme mukavemetinin arttığı tespit edilmiştir. Araştırma vurguları: Kontrplakta vidalama öncesinde kılavuz deliklerine PÜ uygulanması vida tutma performasını önemli ölçüde etkilemektedir.

Anahtar Kelimeler:

Vida çekme, Kontrplak, Kılavuz deliği, Polivinil asetat, Poliüreta

The effects of different variables on the screw withdrawal strength of plywood

Aim of study: The purpose of this study is to investigate the effect of the pilot-hole, screw type, screwing direction, water retention and adhesive on the screw pull resistance of the plywood.Material and Methods: Two types of screws, 3.5 mm and 4 mm in diameter, were used in the study. The supplied 18 mm thick plywood is sized to 50 mm x 50 mm according to TS EN 13446 standards. The pilot-holes were drilled so that 80% of the screw diameter would be used. After the polyvinyl acetate (PVAc) and polyurethane (PU) adhesives were injected into the pilot-holes, screwing was carried out perpendicularly and horizontally to the surface of the sample. Half of the samples were immersed in water for 2 hours before the screw withdrawal test. The results of the tests were interpreted by statistical analysis.Main results: When examining the results, all of the pilot-hole drilled samples showed higher screw withdrawal resistance than the pilot-hole drilled samples. It was also found that the screw withdrawal resistance perpendicular to the surface is higher than that parallel to the surface. When the glue applied pilot-hole specimens were examined, the PU specimens showed higher screw withdrawal strength than the PVAc specimens. A lower screw withdrawal strength was determined when samples were immersed in water. It was also found that as the screw diameter increases, the screw withdrawal strength increases. Research highlights: In is concluded that applying PU in pilot-holes before driving screw in significantly affected screw holding performance in plywood.

Keywords:

Screw withdrawal, Plywood, Pilot-hole, Polyvinyl acetate,

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