Diseño de una prensa electrohidráulica para extracción de manteca de cacao

Abstract

This work presents the design of a high-load electrohydraulic press to separate the fat phase from cocoa liquor through controlled compression, with a target capacity of 100 kg/h. The study defines operating parameters, selects the hydraulic–electric power subsystem, and verifies the mechanical integrity of the assembly. The methodology included 3D CAD modeling, pressing-force calculation using a design pressure of 35 MPa (350 bar), flow rate and power sizing, and structural verification through finite element analysis. AISI 304 stainless steel was used for all product-contact surfaces, while AISI 1018 steel was used for structural members; catalogs and supplier quotations were used for the itemized cost assessment. The press operates in 20 kg batches with a 12 min cycle, achieving a nominal pressing force of approximately 2.56 MN, a required flow rate on the order of 34 L/min, and the selection of a 25 kW electric motor. Structural simulation yielded global displacements on the order of 0.98 mm, with local stress concentrations associated with contact regions and geometric transitions. The consolidated cost estimate resulted in an “operational-ready” value of USD 6,200 for the locally built prototype with a mixed supply strategy (locally manufactured frame and process assembly, complemented by an imported hydraulic cylinder and commercial components), compared to USD 8,349.45 for importing an equivalent press “delivered and installed” in plant. The proposed solution is technically feasible, and the implementation criterion is based on balancing investment, sanitary control, supply risk, and maintainability. Keywords: Finite element analysis, Line-item costing, High-pressure hydraulics, Food-grade stainless steel, Maintainability.