The Research Of Device For Water Requirment Of Normal Consistency And Setting Time Of Portland Cements

With the development of society and economy, every walk of life is developing fleetly. In particular, with the improving of dwelling level and building of a mass of national fundamental construction, the requirement of Portland cements is increased substantially in whole society in recent year. The Portland is one of main building material in construction and is important part of concrete and grout, which is used widely in traffic and national defenses and metallurgy and chemical industry and water conservancy and resident building etc. The physical properties of Portland directly affect the quality and weather resistance of construction, and relevant to safety of people and public properties. In fact, we find that people sometimes pay more attention to the test of soundness and strength of Portland, and neglect water requirement of normal consistency and setting time. At the same time, automatic degree of testing device is low.In this paper, the device that test water requirement of normal consistency and setting time of Portland is researched for resolving the problem that automatic degree of manual device is low. The device mainly contains three parts that include test probe and humid curing box and mechanism that drives test probe in horizontal plane and the device's hard control system. This paper mainly explores and discusses the aspects as following:1. The structure of device is designed, which includes the parameter of device and composition of system and main function, and decides the last structure through compare relative plan;2. The test probe is designed, which includes the design of rotational part and compensation of linearity and creep of force sensor, and design of the device of protecting test probe overload and elevating gear;3. The humid curing box is designed, which includes design of its structure and the selection of sensor and the control of semiconductor cooler and the selection of ultrasonic humidifier;4. The mechanism that drives the test probe in horizontal plane is designed, which introduces the working principles and selection of stepping motor. Device of protecting over range and transformation circuit of position sensor and control software are designed;5. The control system is designed, which includes selection of temperature and humidity sensor and design of circuit. Transformation circuit of A/D and D/A and stepping motor's drive and keyboard and led and memory and interface circuit are designed;6. Serial communication of MUC is introduced. Serial communication between MUC and PC is designed.Finally, this paper summarizes the deficiencies of this paper and extracts some constructive advices for the further improvement.