UA65949A - Method for hydrodynamic control of well drilling - Google Patents

Abstract

Method for hydrodynamic control of well drilling by pressure difference in two points of the flow of washing liquid includes measuring of washing liquid pressure at the manifold of the drill pumps, measurement of the flow rate at the outlet of the well, and determination of the flow rate in the bottom zone of circulation of the well ejection system through the relationship found.

Description

The invention relates to the field of well drilling and can be used in the hydrodynamic control of well deepening for the purpose of operational optimization of the mechanical drilling process.

The known method of determining the flow rate of the medium is based on the use of the dependence on the flow rate of the pressure difference created by the device installed in the pipeline, or by the element of the latter itself

IKremlevsky P.P. Flow meter and quantity counters. - L.: Mashinostroenie, 1989. - 7016 p., p. 101. According to this method, the flow rate of the medium is determined from the ratio that connects the kinematic and dynamic characteristics of the flow that moves through the device or element of the pipeline.

The disadvantage of this method of determining the flow rate of the medium in the near-hole circulation circuit when drilling wells is the impossibility of determining the pressure directly on the holes. This is due to the imperfection of the existing means of transmitting information about the amount of pressure in the wellbore area during drilling to the control panel of the drilling rig due to the significant length of the communication channel, the limitation of its diameter dimensions, the presence of an aggressive environment, variable operating conditions of the elements of the hydromechanical system and other factors

There is also a known method of determining the mass flow rate of the medium (Aust. Sv.SSSR Mo732670, cl. 0111/0001 by the difference in pressures at two points of the flow of this medium. This method allows you to determine part of the mass flow rate in the branching from the main flow, for which one of the pressures is determined mainly flow, and the second - in branching.

This method, like the previous one, requires the direct determination of the pressure difference in the flow, which makes its use in the well impossible.

The method of hydrodynamic control of well drilling is the closest to the proposed one

IAvt.sv.SSSR Mo1121409 A, cl. Е21В47/06|Й, which provides for the measurement of the pressure of the flushing fluid on the manifold of the drilling pumps and its consumption. This method makes it possible to carry out hydrodynamic control of well drilling in the case of using an unbranched system of movement of the flushing fluid, when there are no additional drilling fluid circulation circuits in the near-cut zone of the well. The consumption of flushing fluid in the manifold of the drilling pumps in this case does not differ from the consumption of the wellbore.

However, this method of hydrodynamic control has a low accuracy of determining the flow of flushing fluid at the wellbore when using well ejection systems with an additional closed near-bump circulation circuit without going to the surface, and the value of this flow can be significantly different from the flow of flushing fluid in the manifold of drilling pumps. The difference in flow rates of the flushing fluid in the manifold of the drilling pumps and at the bottom of the well is not taken into account by this method in the case of using a well ejection system, as a result of which the effectiveness of the hydrodynamic control of well drilling is reduced. This, in turn, leads to the wrong selection of the necessary parameters for washing the well and a decrease in the technical and economic indicators of drilling.

The task of the invention is to increase the efficiency of hydrodynamic control of drilling wells by taking into account the flow of flushing fluid in the near-hole circulation circuit and periodically comparing its value with the model.

The problem is solved by the fact that in the known method according to which the pressure difference in two points of the flow of the flushing fluid is determined, which includes the measurement of the pressure and flow rate of the flushing fluid in the manifold of the drilling pumps according to the invention, the flow rate is additionally determined in the downhole circulation circuit of the well ejection system, the value of which is compared with the model, and the flow rate of the flushing liquid is determined according to the established algorithm.

Additional determination of the flow rate of the flushing fluid in the near-hole circulation circuit makes it possible to increase the accuracy of determining the flow rate of the well hole compared to known methods. The use of a calculation algorithm to determine the consumption of flushing fluid makes it possible to avoid direct measurement of pressure values at two points of the flow, which is impossible in well conditions. The periodic comparison of the received value of the flow rate of the flushing fluid in the near-hole circulation circuit with the model allows more effective control of the drilling process, since the deviation of the actual flow rates from the controlled indicators indicates a violation of the normal functioning of the ejection system.

Information about the amount of actual consumption of flushing fluid allows for prompt regulation of the operation mode of the downhole ejection system in order to optimize the process of mechanical drilling.

In particular, in the event that the flow rate of the flushing fluid in the near-hole circulation circuit is insufficient for effective cleaning of the well blowout, it is necessary to increase the performance of the drilling pumps or change the geometric and kinematic parameters of the ejection system parts.

The technical and economic result, which is achieved when using the method, consists in increasing the efficiency of control over the drilling process, as a result of which the mechanical speed of drilling and passage to the bit increases, the costs of materials and equipment operation are reduced. As a result, the application of the invention allows to reduce the cost of drilling wells.

The figure shows the schematic diagram of the well ejection system.

The method of hydrodynamic control of well drilling is carried out by determining the pressure Рn and the flow rate Оn of the flushing fluid in the manifold 1 of the drilling pumps 2 and the flow rate Оv in the near-hole circulation circuit of the ars, formed by the lower part of the drill string 3, the jet pump 4, the bit 5 and the channel of the annular space 6. Moreover, in the general case, the value of the consumption of Ov exceeds the value of the consumption of On by the value of the consumption of СО); injected flow. Manometer 7 is used to determine pressure Рn, and flow meter 8 is used for flow On. The controlled value of the flow of flushing liquid in the additional circulation circuit, with which the actual values are compared, is determined analytically in the process of jointly solving the equations of the characteristics of the jet pump and the hydraulic system in which it working.

The method is carried out as follows.

With the help of manometer 7, the value of the pressure of the flushing fluid Рn in the manifold 1 of the drilling pumps 2 is determined, the flow rate of the flushing fluid On at the entrance to the well is determined with the help of the flow meter 8, or at the exit from the well using the volumetric method. We use the obtained values of pressure Рn and flow Оn to determine the flow of flushing fluid at the wellbore from the ratio:

OB s. "Stand up probably

Kd de Рn - pressure value on the manifold of drilling pumps;

Kk, Kz, Kern, Kd - proportionality coefficients for the hydraulic channels of the drill string and the annular space, the working nozzle of the jet pump and the flushing system of the bit, which are determined in the process of research;

It is the consumption of flushing fluid at the exit or entrance of the well.

The possibility of applying the proposed algorithm is determined by the existence of the dependence of the flow rate on the difference in pressures determined at the initial and final sections of this flow. The value of the pressure Рn on the manifold of the drilling pumps is directly proportional to the flow rate of the flushing fluid and the hydraulic losses in the drill string 3, the jet pump 4, the flushing system of the bit 5, in the channel of the annular space 6.

The obtained value of the flow rate of the flushing fluid on the wellbore is compared with the control value, which is determined by jointly solving the equations of the characteristics of the pump and its hydraulic system.

Example

The depth of the well is not 1000m; productivity of drilling pumps On-0.02m3/s; outer diameter of the drill string ykz-:0.127m; the inner diameter of the drill string is 0.109 m; borehole diameter Os-0.216m; the diameter of the holes of the bits of the bit is 0.018m; ultimate shear stress t- pa plastic viscosity p.- orozpa: s; density

Sho 3. washing liquid water - 1000 kg/m"; the number of nozzles of the M-3 bit; the consumption coefficient of the working nozzle of the jet pump "PH 7,095; the coefficient of consumption of bit nozzles "A 7,095.

Flow rate in the drill string and annular space: m - SALT WIFE with -olaamus; t:9 sq.m. 314.0109 ma - et - --- pVR och zhh - О833m/me; t (bo -4c) evil (o21c -0127 )

San Venan parameter for drill string and annulus:

Zet - hakvo 009 67,786; p:Uk o 0003.2144 bepa - Osoka) 40216027 4 vu, pejZh 0.003.0.833

Reynolds number for the drill string and annular space: age -- 5 .« "K86 kov - 00 VIZA UV, tvotve - 6334427; prak booz- (1 EVIL. b b

Transport - 2-8 bo -bkz) 1000.0833 ovvv 27). 1313988. prov. oooh-| t TT) b b

Coefficient of linear hydraulic resistance for the drill string and annular space: 164 1364 zkh - OVT OIL. oo;

Carrier 63344277 min -- 20073.

Not 1313,988

Proportionality coefficients for the drill string and annular space: кк - авта - свт оо 100,000 -184483.105; aqv 0lo9

Ka - 0811-X85- Neo: p U 0,811.0,073.1000.1000 5 -713815.-106. (Os -akz Y (Os aka) (0216-0427) (0.216 col27)

Proportionality factor for the working nozzle: р р 1000 6

Krn- 578 27 Z-62- - oo 5 -- -I and dv 5 - 5619,058.107. "RN . . 2-cen- lodrn 2.0952. Zl415:0027 4 4

Proportionality factor for the bit flushing system:

Ka appetite tlu ZBUM2 TO "Sun" "f . 2 and 2.2. city of Yad 2.0952. z.Zla15:00187 d 4 A

Consumption of flushing fluid on wellbore holes: ов - Рн-(Кк Кз Кен) Ой | 005-106 (184483 --713,815--5619,058).109.0022 |. in Ka Y 951642-106 Y - 0.42625m3 / s - 42.625 lL / s.

Re (from / --05

Shi Chu 7

Shi NI

Mon at 7

Myr ay5--- ia / 6 and (in and and where

S b

Claims (1)

The method of hydrodynamic control of drilling wells based on the pressure difference at two points of the flushing fluid flow, which includes the measurement of the flushing fluid pressure on the manifold of the drilling pumps and the flow rate at the exit from the well, which is distinguished by the fact that the flow rate in the wellbore is additionally determined. while using the ratio: in- with Kk, where Pn is the pressure value on the manifold of the drilling pumps; Kk, Kz, Kn, 77 - proportionality coefficients for the hydraulic channels of the drill string and the annular space, the working nozzle of the jet pump and the bit flushing system; It is the consumption of flushing fluid at the exit or entrance of the well.