{'fraction_non_alphanumeric': 0.020999275887038378, 'fraction_numerical': 0.002172338884866039, 'mean_word_length': 5.169642857142857, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Design & fabrication of closed loop hydraulic press to control pressure & flow

The present paper describes the design and fabrication development of a 250kN closed-loop hydraulic actuated press to control Force, velocity and position during stamping operations as well as mechanical tests. The press has one hydraulic servomechanism: a hydraulic cylinder, driven by a servo-solenoid P/Q valve, to support the operation; The press is equipped with a pressure sensor installed in the cylinder chamber for indirectly measuring the pressing force. On the press it is also possible to measure the position of the upper plate by using a micro-pulse linear transducer, which creates a precondition for the realization of a hybrid force /position /velocity-control algorithm. The control algorithms and monitoring process are implemented on a real-time hardware board. They are programmed in the LABVIEW software. Based on the experimental results, it can be concluded that electrically actuated control components supported by the appropriate computer programs make it possible to improve the characteristics of the hydraulic systems required in modern industrial plants. The software setup allows the implementation of a hybrid controller (force + position + velocity) for the hydraulic cylinder in such a way that it will be easy to switch between force, position and velocity control.