Design And Research Of Emulsion Automatic Proportioning System

Fully mechanized coal mining working face is an important energy coal-mining platform in China.Emulsion is an important working medium for hydraulic equipment such as hydraulic shield suppor and so on.The working coverage of fully mechanized mining face is large,so the consumption of emulsified fluid is huge,too.Meanwhile the precision of emulsified fluid concentration is required when hydraulic equipment works.Under the working background of large flow rate,the high concentration of emulsified oil will greatly increase the cost of emulsified fluid,enormously reduce the defoaming ability of emulsified fluid,and easily swell the sealing equipment of rubber and other materials.When the emulsified fluid has bubble cavitation,the sealing equipment damages.It makes the service life of coal mining equipment reduce.At the same time,once the system leaks high proportion of emulsified oil,it will cause environmental damage-Great Pollution.On the contrary,if the concentration of emulsified oil is too low,the hard water resistance,lubricity and corrosion resistance of the emulsion will reduce obviously.A large number of single hydraulic props damaged in fully mechanized mining working face because of the serious corrosion of cylinder and piston every year.Therefore,how to configure the precise concentration of emulsifier makes a great significance to the study of fully mechanized mining working face.Most of the existing emulsifier mixing systems use concentration sensors to measure the configurated emulsifier and feedback the concentration signal to control the closed-loop concentration control system.However,due to the wide coverage of fully mechanized mining working face,long response time and feedback time,also the hydrophilicity of emulsified oil,it is difficult to measure the concentration of the concentration sensor,and the measurement accuracy is not high.As a result,the existing closed-loop control system cann’t meet the accuracy requirements of the automatic emulsification ratio system very well.On this basis,a closed-loop control emulsifier automatic mixing system with plunger pump as actuator and real-time flow as feedback signal is proposed.Specific scheme is as follows: Calculate and select two efficient three-plunger pumps to transport hydrostatic water and emulsified oil respectively,and select different emulsified concentration modes through switches.After determining the proportion concentration,the frequency converter starts two motors at the initial frequency,and the motor drives the plunger pump to work.A high-precision turbine flow sensor designes to monitor the real-time flow of hydrostatic water.The collected flow signal transmittes to the programmable control system.According to the relationship between flow rate and motor frequency,the system calculates the frequency of the oil circuit motor to be adjusted,and feeds this signal back to the oil circuit control frequency converter for variable frequency speed regulation of the oil circuit motor.By controlling the volume ratio of emulsified oil and hydrostatic water in the input system,the accuracy requirement of the emulsified liquid mixing system realizes.Programmable controller uses to realize automatic proportioning of fully mechanized mining face in mine,and alarm devices such as emergency stop button and alarm indicator light add to ensure the stable operation of the system and increase the safety and reliability of the system.With regard to the mixing of hydrostatic water and emulsified oil,the author innovatively proposes the use of high-pressure contra-jet nozzles.In the form of atomizing nozzle,hydrostatic water and emulsified oil with a certain pressure and a certain speed will atomize into droplet molecules,which will increase the contact area and dispersion of the two molecules.The kinetic energy of the converter itself will make the mixing of the two more uniform and the operation more simple and reliable.The AMEsim simulation analysis of the above scheme carries out,and based on the results of simulation analysis,we build the experimental platform of emulsifier automatic mixing system.At the basis of the original scheme,a turbo flowmeter addes to the emulsified oil branch to measure the real-time flow of the oil system.On the simulated test bench,using the emulsifier automatic mixing system to allocate the three different concentrations of emulsifiers automatically.Found a volume ratio of emulsified oil and hydrostatic water in the input system to be within the error range of configuration requirements.The design scheme has achieved the precision requirement of the automatic emulsification mixing system.Summarized and analyzed the possible faults in the operation of the system and list the solutions.It shows that the design scheme can effectively solve the problem of high precision automatic ratio of emulsified liquid in fully mechanized mining face.The thesis has 72 figures,7 tables and 110 references.