Wood-based panel surface soundness testing machine

1.     Introduction

This testing machine is to assess strength or quality of bonding between the particles or fibres at the surface of a wood-based board and the layer below(unfaced panel) or between the coating materials and the underlying board(overlaid wood-based panels).The strength or quality is measured by the tensile load required to pull off a defined surface area of overlaid or unfaced panel.

2.     Test

Wood-based panel sample size and quantity:  8 test pieces, each 50mm X 50mm, shall be taken from each wood-based board to be tested.

Test method:

1)     A circular groove with inside diameter of 35.7±0.2mm shall be cut into the surface the wood-based panel test pieces(see below figure). For unfaced panels, depth of circular groove is 0.3±0.1mm and for overload wood-based panels, the groove shall not penetrate more than 0.3mm into the wood-based panel.

2)     Use a hot-melt adhesive spread evenly across the face of the steel pad. The centring frame is used to position the pad exactly on the test piece. Whilst in the centring frame the pad shall be pressed onto the surface of the wood-based panel test piece. If the wood-based panel to be tested are thinner than 15mm, the wood-based panel test pieces shall be strengthened by bonding a 50mm X 50mm steel plate of at least 10mm thickness to their underside.

3.     Technical parameters of testing machine