Research On Measurement System For Kinematic Viscosity Of Petroleum Products

With the Daqing oilfield production decreased year by year, mechanical equipment wear,according to the cycle of oil replacement has become more and more important, is to evaluate whether the oil viscosity is one of the important indicators of performance can meet the need of work, in the national standard method for measuring viscosity of many, including rotational viscometer method, capillary method, the falling ball method, single multi ball method. Among these methods, capillary method because of its simple operation, high accuracy, by the vast number of petroleum products inspection staff of all ages, more important is the only instrument it is still able to calibrate viscosity measurement.Because the capillary method has been widely used, so a lot of problems have been exposed, for a long time in the kinematic viscosity of petroleum products test system has not been perfect, the workload of inspectors, for the latter part of the data record, data management is very complex, which for me is "the leading domestic, international first-class" goal, obviously is not appropriate, therefore, we according to the routine of viscosity detection and using the experience of some of the kinematic viscosity testing the idea of current research, an automatic detection system based on the capillary method.The specific contents are now commonly used in capillary viscometer method based on a plurality of measurement, by placing the capillary in the constant temperature bath has reached the test environment, due to the pressure difference on both sides there are capillary,we can easily realize the measurement of the fluid viscosity. In this set of automatic determination of kinematic viscosity of system, the computer software control instrument there is a communication between the communication protocol, the experimental environment for the measurement of viscosity temperature control, measurement results automatically read the measured sample flows through the capillary, the upper and lower ends of the time,automatic recording the sample viscosity, the automatic calculation of the sample to be measured, the visualization of the previous test oil viscosity data query and save functions are realized by the communication module.The system adopts Delphi as the basis of the system software, the MCU as the core,through the application of computer software programming, to achieve the temperature environment to meet the experimental conditions. Through the comprehensive use of the serial communication software design and implementation to achieve the database and VCL Delphi component, to meet the different requirements of the experimental conditions of the operator. The design ideas of some of the programming model of software engineering, using Delphi as a development tool for the overall software design and development, greatly improving the efficiency and speed of development of software.Daqing oilfield technical supervision center of product quality supervision and inspection and the oil chamber of the existing two kinematic viscosity tester, the degree of automation is not high, in the detection process, the whole process is complex, needs manual operation, increase the intensity of labor inspector. This study can improve the work efficiency of the kinematic viscosity of petroleum products, fast and accurate monitoring data were obtained from aspects of theory and technology to solve the problems related to the oil viscosity, improve the existing means of manual testing, automated testing of oil viscosity, to further improve the work efficiency and the accuracy of the oil viscosity. In the temperature control, according to the actual situation of our laboratory, the PT100 platinum resistance and optimization of circuit PID temperature sensor, combined with the semiconductor refrigeration piece is composed of a temperature control system, which can make the error of constant temperature water bath within plus or minus 0.2 DEG C, in accordance with the provisions of national standards for kinematic viscosity measurements in fluid; liquid level detection, infrared sensor device for liquid level detection method was used to determine the start and end time, through 4 successive measurement and data processing, compared with the level of manual timing and the human eye detection using traditional, far infrared sensor instead of human eyes, reduce the detection error, reduce the labor intensity of operators, and improve the degree of automation instrument; in human-computer interaction, measuring instrument using Delphi development and design of intelligent kinematic viscosity of petroleum products in the interface of host computer and data processing software, the user can through the man-machine interface for data management, query, modify, report printing and other operations.