A mechatronic design synthesis for very low flow control valves

The means by which the control of very low flows in the region of 0.1-400ml/hr using valves with microchannels (<250μm) is not well defined. This work presents a review of existing literature that contributes to the understanding of controlling very low flows. Mechatronic principles are used to bring new understanding to the field of very low flow control using needle valves. Flow rate experiments were conducted using a mechatronically controlled needle valve and a novel flow measurement device constructed for the purpose, from which an analytical flow model is developed. Details of a linear actuated needle valve are given along with open loop and closed loop control systems developed for the purpose of accurately controlling very low flows. The open loop system is derived from the valve operating principles enabling an efficient method of modelling the valve flow characteristics for the purpose of control. The closed loop method, incorporating gain scheduling is capable of controlling flows to within 0.0016ml/hr at low flows. A prototype lubricant dispensing system using a low flow needle valve was tested in an industrial environment. A design synthesis is developed by consolidating the knowledge gained from these studies is presented. This discusses the all main factors affecting the design and operation of needle valves for the control of very low flows while describing practical solutions to the problems commonly encountered

In-process monitoring and quality control of hot forging processes towards Industry 4.0

The importance of quality control in any manufacturing process has always been recognised. However, now more than ever before, it is a key requirement in order for manufacturing companies to remain competitive in the digital age. Because of the complexities and globalization of the manufacturing supply chain, real-time product quality analysis has become an important issue in the global manufacturing industry. However, in the metal forging industry, the attainment of efficient real-time quality control within forging processes has been faced with many technological challenges. These challenges are associated with the need for more sophisticated process modelling and simulation tools, cost-effective self-tuning sensors and a lack of robust and efficient in-process monitoring and quality control technologies for the forging industry