| 摘要 |
<p>The invention relates to a process and a device for determining the shear strength of wood pellets. According to the invention, the process consists in fixing the shearing device in the universal testing machine by clamping the device upper and lower parts (1 and 2), respectively, between the jaws (3 and 4) of the testing machine and introducing a number of five pellets (6) into the five calibration orifices (5) of the device, after which the testing machine is driven at a speed in the range of 5...10 mm/min, until the five pellets (6) are broken while recording the breaking force, after which the pellet shear strength is calculated taking into account the number of pellets and their circular shearing surface. The device, as claimed by the invention, consists of two metal plates (A and B), i.e. an upper one and a lower one, respectively, which slide onto one another frictionless, with a play of 0.4 mm, the upper plate (A) having the shearing head in the shape of a knife of high sharpening angle, in the range of 80...90° meant to prevent bending or compression, while the lower plate (B) plays the role of a counter-knife and has five orifices (C) calibrated at sizes in the range of 6...8 mm, with variations of +0.2...-0.0 mm.</p> |
