Model Of Hydraulic Press Research Articles

Design of Nonoverconstrained Energy-Efficient Multi-Axis Servo Presses for Deep-Drawing Applications1

Servo-actuated presses may provide maximum pressing force at any ram position in the same manner that hydraulic presses do, while offering several benefits in terms of precision, energy-conversion efficiency, and simplicity, due to their lack of hydraulic circuitry and oil. Several press builders have developed servo-actuated presses; however, issues relating to overconstrained multi-axis architecture have been disregarded. This study proposes an innovative method to avoid overconstrained architectures in multi-axis presses, by implementing a family of modular parallel mechanisms that connect multiple servo-axes to the press ram. Parallel mechanisms, which can be applied in several fields of robotics and industrial automation, exhibit important benefits for the application at hand, including high-load capacity, stiffness, and compactness. A biaxial industrial servo press prototype with a nonoverconstrained and modular architecture was built and presented as a proof of concept. Each axis comprises a servomotor, a gearbox reducer, and a ball-screw transmission. It is shown that such a press may be constructed from commercially available components, achieving high energy efficiency and high press force with relatively simple construction. A direct comparison with an equivalent hydraulic-press model is carried out, thus highlighting the servo press energy efficiency.

Speed Control of Hydraulic Press via Adaptive Back-Stepping

This paper is concerned with speed control of hydraulic press system. First, the mathematical model of hydraulic press is derived from its physical characteristics. Then, based on this model, the so-called back-stepping approach is used to design a speed controller. Moreover, in order to overcome the unknown deformation resistance and some other resistance, an adaptive control scheme is introduced to this controller. Finally, a real hydraulic press model is used to validate the proposed method. Simulation results show that the adaptive controller deals with the nonlinearity effectively, and the tracking performance of the system is good.

Simplified Static Holographic Evaluation Method Omitting The Zero-Order Fringe

A simplified static multi-interferogram evaluation method is proposed. With its aid the absolute fringe order number can be determined in the absence of the zero-order fringe. The method can be applied to measuring 3-D displacement due to static/dynamic load in industrial environments. Data needed for determining 3-D displacement are stored on four independent interferograms. The recording holographic interferometer is presented. An experimental investigation of a hydraulic press model has been performed to illustrate the effectiveness of the proposed technique.

Increasing the utilization coefficient of metal in the production of valve balls

This article describes a production technology of blanks for valve balls which improves the utilization coefficient of metal. Pressing of the shaped blanks, which consists in combining forming and bending, is effected with punch and forming die on a hydraulic press model with a force of 4000 kN, with heating in a compartment-type gas furnace. It is determined that making the blank in a crosslike shape helps reduce metal expenditure per ball and improve the utilization coefficient of metal. The new technology for the production of valve balls with a rational sheet cutting pattern makes it possible to save 340 tons of rolled sheet annually and a considerable amount of electric power, to reduce gas consumption for cutting and heating, and to save on cutting tools.