Research On High Pressure Bi-directional Elliptical Gear Flowmeter

As an important style of flowmeter, Elliptical Gear Flowmeter has been widely used in many sections of national economy and social surroundings due to its advantages such as positive displacement, high precision, low fluence of flow temperature and pressure loss, easy fixing, stable performance, and excellent repeatability. But traditional elliptical gear flowmeter can be used only in low pressure. Improving its performance can be beneficial to enhance the application situations, better satisfy the market requirements and push the development of the flowmeters.The thesis deeply analyzed and researched the elliptical gear flowmeter, utilizing theory analysis, finite element numerical computation and experimental study. A new style high pressure bi-directional elliptical gear flowmeter is put forward. The characteristics of gear structure is analyzed and the graph of impulsive engaging in constant flows is received. The leakage and pressure loss of elliptical gear flowmeter is discussed, too. The new plan of magnetic-sensing detection is presented, whose elements and structure parameters are selected with finite element numerical simulation. The test-rig is put up, and the experimental results indicate that the error of flowmeter is ±0.5% when it is in pressure of 21MPa, ±0. 5～3%when it is in pressure of 31.5MPa. Twin-channel magnetic-sensing detection can show the direction of flow. This flowmeter can endure high pressure of 31.5MPa, and its pressure loss is low to 0.15MPa. This high pressure bi-directional elliptical gear flowmeter can endure high pressure of 31.5MPa, measure bi-directional flows, with twin-channel magnetic-sensing detection and low pressure loss. These can be used for the further research.In chapter 1, based on the research information widely overseas, the history of flowmeters is introduced, with their classification and comparison. The development, structure character, working principle, advantage and disadvantage of elliptical gear flowmeter are discussed respectively.In chapter 2, a new style high pressure bi-directional elliptical gear flowmeter is presented, with its structure and principle being introduced. The characteristics of gear structure and its key parameters including pitch curve and tooth profile are analyzed. The graph of impulsive engaging in constant flows is received.In chapter 3, the main characters of elliptical gear flowmeter are discussed,...