MACHINE DESIGN PARAMETERS: RUPTURE FORCE AND DISPLACEMENT OF MACAW PALM ENDOCARP
Bruno Henrique Macedo Lisboa1; Geice Paula Villibor1; Joseph Kalil khoury Junior1; Francisco de Assis de Carvalho Pinto1
1 Universidade Federal de Viçosa
doi:10.20906/CPS/COB-2015-1983
Resumo
One of challenges to change from subsistence to commercial exploitation of macaw palm is to develop planting technology. To implement a commercial macaw field, pre-germinated seeds should be used. The seed has to be intact, without damage, such as cracks or chipping. To access the seed, the macaw endocarp should be broken. At the present, it has been done manually by using a bench vise. The mechanical properties of the macaw endocarp have to be known for developing a machine to extract the seed from the endocarp. This work aimed to evaluate the compressive force required to break the endocarp and the displacement imposed on it, without damage the seed. In the tests, the macaw fruit husk was manually removed, keeping the mesocarp (pulp) that surround the endocarp. A bench vise with a load cell and a Linear Variable Displacement Transducer was used to compress the fruit until to break the endocarp. Data collection was obtained through an acquisition system aided by LabView® software. The endocarp rupture force and the fruit displacement were evaluated as a function of the pulp condition (oily and dry), the direction of application of force (longitudinal and transversal) and the fruit diameter class (three classes from 30 to 38 mm). The experiment was conducted in a completely randomized design in a factorial 2 x 2 x 3, with ten replications, resulting 120 experimental units. Variance analysis was performed to verify the influence of the above factors on the compression force and displacement of the macaw fruits. The average compression force and displacement were compared using the Tukey test at 5% probability. The endocarp compression force was influenced by fruit diameter class (DC), pulp condition (PC) and direction of force application (FAD). The interaction between factors DC and FAD; PC and FAD also influenced the force. The endocarp rupture force varied from 5.81 to 8.85 kN, when considered the diameter class and application force direction interaction. Transverse force was higher than longitudinal one for t
Palavras-chave: machine design; mechanical properties ; instrumentation