The Research On Low Yield Wells Using Output Metering With Dynamometer Card

The output metering technology of oil well, which is commonly used in our country, is that several wells output in a range was transported to a metering station or test station nearby,and then it was re-transported to the oil processing or storage station far-away.This kind of method of production metering is neither economical nor appropriate for the development of oil-company. How to change it to realize measure uninterrupted and to simplify the processing sequences and increase economic effect in home oil production is an important problem.The production metering technology based on dynamometer card is used to develop to solve the problem of single well output metering. Although this kind of method has partly been applied to oil field production, there are still some problems left unresolved. However,special cases existed in low oil penetration area. This paper completes those tasks and makes some research.Matural quadratic regression is used in this paper, Quadratic regression analysis the liquid production of different stage in this paper, it can help to calculate the liquid production with indicator diagram.This paper introduces the operation principle of pumping unit and oil-well pump, and explains the geometrical characteristics of theoretical and fault indicator dynamometer firstly. The one-dimensional wave equation is used to deduce pump dynamometer card with surface dynamometer card as boundary value. The method that solves this wave equation is Fourier series. This paper analysis the impact that the different values of damping coefficient influence the liquid yield. The mixed liquid in the tubing is compressed, after the liquid arrived wellhead, the gas dissolved in the liquid will separate out, so the discharging liquid of underground is not equal to the ground production. This paper presents the method for calculating the volume coefficient of mixture under pump discharge pressure to convert the ground liquid production.It is the key of the indicator diagram measure oil technology to determine effective plunger stroke. This paper researches the relationship between pump dynamometer card, opening and closing of the valve position and the effective stroke of the plunger with the pump dynamometer data, and establishes calculation model of the pump characteristic curve, finds the two largest curvature changes point in the high, low load, gets the valve opening and closing point, so as to determining effective plunger stroke. According to the working principle of pump and load analysis, this paper discusses theoretically value opening and closing points and presents an accurate method of extracting the valve opening and closing points of surface dynamometer cards using load line. The results show that this approach is reliable.Making the software for the automatic soft system of low oil well dynamometer card based on MATLAB GUI. The soft includes modules of data entry, well productivity prediction, data output, helping and so on, which make the software interface and operation more convenient, and meet the user requirements. The average relative error between the calculated and measured is 6.60% by using this software calculates producting of field collection oil well aboard. The actual calculating of dynamometer cards certificate feasibility of output metering with dynamometer card.