A method for adjusting pumping speed of a pumping unit well

Abstract

The application discloses a pumping unit well stroke adjustment method, comprising judging whether the pumping unit well meets the conditions of increasing or decreasing the stroke; if the conditions are met, calculating the increased parameter operating frequency f 后上 or the decreased parameter operating frequency f 后下 ; judging whether the increased parameter operating frequency f 后上 exceeds the upper limit frequency of motor output f 上 , when f 后上 < f 上 , the increased parameter operating frequency f 后上 is executed; when f 后上 ≥ f 上 , the upper limit frequency of motor output f 上 is executed; judging whether the decreased parameter operating frequency f 后下 exceeds the lower limit frequency of motor output f 下 , when f 后下 ≥ f 下 , the decreased parameter operating frequency f 后下 is executed; when f 后下 < f 下 , the lower limit frequency of motor output f 下 is executed; if the conditions are not met, the stroke is not increased or decreased; the problem that the work load is large when the frequency is adjusted to increase or decrease the stroke is effectively solved.

Description

Technical Field

[0001] This disclosure relates to the field of oil pumping unit well parameter adjustment, specifically a method for adjusting the pumping unit stroke rate. Background Technology

[0002] When pumping wells operate at appropriate submersion and flowing pressure, they ensure high formation fluid production and high pump and system efficiency. If the submersion is too low, pump cavitation and liquid hammer can easily occur, reducing pump and system efficiency, and also causing rod and tubing vibration that shortens system lifespan. If the submersion is too high, the pumping well's fluid production cannot be fully exploited, impacting economic benefits.

[0003] With the widespread use of frequency converters, frequency conversion adjustment has advantages such as convenient operation and ease of implementation, making it the preferred method for parameter adjustment. However, there is currently no clear guidance method for parameter adjustment on site, requiring technicians to rely on experience to repeatedly try to adjust the operating stroke. The parameter adjustment process greatly increases the workload of personnel, and the effect of the pumping well after adjustment is not ideal. Summary of the Invention

[0004] In view of this, this disclosure provides a method for adjusting the stroke rate of an oil pumping unit, which solves the problem that adjusting the stroke rate of a variable frequency pump requires technicians to rely on experience and make repeated attempts, resulting in a large workload.

[0005] To achieve the aforementioned objective, the method for adjusting the stroke rate of a pumping unit well includes adjusting the stroke rate upwards and downwards; wherein:

[0006] Determine whether the pumping well meets the conditions for increasing or decreasing the stroke rate;

[0007] If the above conditions for increasing the stroke frequency are met, calculate the operating frequency f of the pumping unit well. 后上 Determine the operating frequency f of the adjusted parameter. 后上 Does it exceed the upper limit frequency f of the motor output? 上 When f 后上 <f 上 Execute the above-mentioned upward adjustment of the operating frequency f 后上 When f 后上 ≥f 上 Execute the upper limit frequency f of the motor output. 上 If the conditions for increasing the stroke rate are not met, no adjustment for increasing the stroke rate will be made for the pumping well.

[0008] If the conditions for reducing the number of strokes are met, calculate the reduced operating frequency f of the pumping unit well. 后下 Determine the reduced operating frequency f. 后下 Does it exceed the lower limit frequency f of the motor output? 下 When f 后下 ≥f 下Execute the down-adjustment parameter operating frequency f 后下 When f 后下 <f 下 Execute the lower limit frequency f of the motor output 下 If the conditions for reducing the stroke rate are not met, the stroke rate of the pumping well will not be adjusted downwards.

[0009] In this disclosure and possible embodiments, the submergence L of the pumping well before the measures are obtained. f前 and operating frequency f 前 Data, using indicator diagrams to calculate the pump fill degree η before the measures. 前 According to the pump fill degree η 前 Sinking degree L f前 and operating frequency f 前 The data is used to determine whether the pumping well meets the conditions for increasing or decreasing the stroke rate.

[0010] In this disclosure and possible embodiments, the pump fill degree η before the pumping unit well measures 前 It equals the quotient of the effective stroke of the plunger before the action and the total stroke of the plunger.

[0011] In this disclosure and possible embodiments, the condition for increasing the stroke rate is that the pump fill degree η is satisfied simultaneously. 前 ≥95%, Sinking degree L f前 ≥200m and operating frequency f 前 ≤50Hz;

[0012] The condition for reducing the number of strokes is that the pump fullness η is satisfied simultaneously. 前 <60%, Submersion degree L f前 <200m and operating frequency f 前 >30Hz.

[0013] In this disclosure and possible embodiments, the upper limit frequency f of the motor output is... 上 The lower limit frequency f of the motor output is in the range of 61Hz to 80Hz. 下 The range is between 10Hz and 29Hz.

[0014] In this disclosure and possible embodiments, the operating frequency f of the pumping unit well is adjusted upwards. 后上 The calculation method is as follows:

[0015] Set a reasonable submersion level L f后 Calculate the depth h of the dynamic liquid level after the measure. 后 Based on the dynamic calculation formula for oil well inflow, the daily fluid production Q after the measures are predicted. 液后 After setting the measures, the pump fill degree η 泵后 Calculate the operating frequency f of the pumping unit well. 后上 ;

[0016] The formula for the calculation is:

[0017]

[0018] In the formula, Q 液后 The daily liquid production after the measures, m 3 / d;A p Let m be the cross-sectional area of ​​the plunger. 2 K is the production coefficient; i 减 P is the ratio of the motor speed to the output shaft speed of the gearbox; 极 η represents the number of pole pairs of the motor; η represents the pump fill degree. 泵后 ,%.

[0019] In this disclosure and possible embodiments, the daily liquid production Q after the measure 液后 The prediction formula is:

[0020]

[0021] In the formula, Q 液前 The amount of liquid produced the day before the measure; P wf (h 前 ) represents the bottom hole pressure of the oil well before the intervention, in MPa; P wf (h 后 ) represents the bottom hole pressure of the oil well after the treatment, in MPa; P R This represents the pressure in the middle of the oil reservoir, in MPa.

[0022] In this disclosure and possible embodiments, the formula for calculating the bottom hole pressure of the oil well before the measure is:

[0023] P wf (h 前 )=ρ L g(HL)+ρ′ L g(Lh 前 )+P e ;

[0024] The formula for calculating the bottom hole pressure of the oil well after the aforementioned measures is:

[0025] P wf (h 后 )=ρ L g(HL)+ρ′ L g(Lh 后 )+P e ;

[0026] In the formula, H is the depth of the middle part of the oil layer, m; L is the pumping depth, m; h 后 h represents the depth of the dynamic liquid level after the measures are taken. 后 =LL f后 ,m;Pe ρ is the wellhead casing pressure, MPa; ρL is the density of the fluid mixture in the formation, kg / m³. 3 ;ρ′ L The density of the fluid in the well is kg / m³. 3 .

[0027] In this disclosure and possible embodiments, the pump fill degree η after the measure 泵后 The setting range is between 80% and 90%.

[0028] In this disclosure and possible embodiments, the down-regulation operating frequency f of the pumping unit well 后下 The calculation formula is:

[0029] f 后下 =η 泵前 ×f 前 / η 泵后 .

[0030] This disclosure has the following beneficial effects:

[0031] The method disclosed herein for adjusting pumping frequency in oil wells involves adjusting the frequency upwards based on optimal pump fill level and aiming for stable production under reasonable flow pressure, thereby maximizing daily fluid production and optimizing system efficiency. Adjusting the frequency downwards, on the other hand, aims to improve system efficiency without reducing fluid production after adjustments, ensuring that pumping parameters match the formation's fluid supply capacity, achieving well supply and drainage coordination, and guaranteeing efficient production under reasonable submersion and flow pressure. Therefore, this invention can calculate the optimal upward and downward pumping frequencies for oil wells, providing guidance for on-site parameter adjustments, significantly reducing the number of manual adjustments and the workload associated with manual parameter adjustments. Attached Figure Description

[0032] The above and other objects, features, and advantages of this disclosure will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0033] Figure 1 This is a flowchart of the pumping unit well adjustment method according to an embodiment of the present disclosure;

[0034] Figure 2 This is a flowchart of the downhole pumping method according to an embodiment of the present disclosure. Detailed Implementation

[0035] The present disclosure is described below based on embodiments; however, it is worth noting that the present disclosure is not limited to these embodiments. In the detailed description of the present disclosure below, certain specific details are described in detail. However, those skilled in the art will fully understand the present disclosure for the parts not described in detail.

[0036] Furthermore, unless the context explicitly requires it, the words "comprising," "including," and similar terms throughout the specification and claims should be interpreted as including rather than exclusive or exhaustive; that is, meaning "including but not limited to."

[0037] Figure 1 This is a flowchart of the pumping unit well stroke adjustment method according to an embodiment of this disclosure; by Figure 1 As shown: The method for adjusting the stroke rate on the pumping unit well includes the following steps:

[0038] Step 1: Obtain basic data before oil well intervention, including operating frequency f 前 Indicator diagram, daily liquid production Q 液前 、Dynamic liquid level h 前 Sinking degree L f前 Water content f of surface produced liquid w前 and input power P 前 Calculate the pump fill degree η before well intervention using dynamometer diagrams. 泵前 and improve system efficiency η′ 系前 ;

[0039] η 泵前 =S 有效前 / S 总 ;

[0040]

[0041] Among them, Q 前油 Daily oil production on the surface before the measures, m 3 / d;ρ o Crude oil density at ground level, kg / m³ 3 g, acceleration due to gravity, m / s² 2 ;f w前 Water content of surface-extracted liquid before the treatment; P′ 油 Crude oil power kW; P 前 Before the measures, the system input power was kW; S 有效前 For the effective stroke of the plunger before the action; S 总 This represents the total stroke of the plunger.

[0042] Step 2: Based on the pump fullness η before the measures are taken 前 Sinking degree L f前 and operating frequency f 前 Data is used to determine whether the oil well meets the conditions for increasing the stroke rate; the preferred conditions for increasing the stroke rate in this disclosure require that the pump fill degree η be met simultaneously. 前 ≥95%, Sinking degree L f前 ≥200m, frequency f 前 ≤50Hz.

[0043] Step 3: If the conditions for increasing the stroke rate are met, ensure the pump is fully filled (η) after the measures are taken. 泵后 Based on the principle of optimality, the goal is to produce under reasonable flow pressure; a reasonable submersion degree L is set. f后 Based on the dynamic calculation formula for oil well inflow, the daily fluid production Q after the measures are predicted. 液后 After setting the measures, the pump fill degree η 泵后 The preferred measures set in this disclosure result in a pump fill degree η. 泵后 The optimal range is between 80% and 90%; calculate the operating frequency f of the adjusted parameter. 后上 The specific calculation process is as follows:

[0044] h 后 =LL f后 ;

[0045] P wf (h 前 )=ρ L g(HL)+ρ′ L g(Lh 前 )+P e ;

[0046] P wf (h 后 )=ρ L g(HL)+ρ′ L g(Lh 后 )+P e ;

[0047]

[0048]

[0049]

[0050]

[0051] In the formula, P wf (h 前 ) represents the bottom hole pressure of the oil well before the intervention, in MPa; P wf (h 后 () represents the bottom hole pressure of the oil well after the treatment, in MPa; J o P is the oil recovery index. R H is the pressure at the mid-reservoir, in MPa; H is the depth at the mid-reservoir, in meters; L is the pump hanger depth, in meters; h 后 The depth of the dynamic liquid level after the measure, in meters (m); P e ρ is the wellhead casing pressure, MPa; L The density of the liquid mixture within the formation, kg / m³ 3 ;ρ′ LThe density of the fluid in the well is kg / m³. 3 Q 液后 The daily liquid production after the measures, m 3 / d;A p Let m be the cross-sectional area of ​​the plunger. 2 K is the production coefficient; i 减 P is the ratio of the motor speed to the output shaft speed of the gearbox; 极 This represents the number of pole pairs of the motor.

[0052] Among them, the reasonable submersion degree L f后 Based on conventional techniques in this field, and taking into account different oilfields, blocks, fluid properties, reservoir properties, pump diameters and depths, reservoir supply capacity, etc., a comprehensive study is conducted to formulate a reasonable submersion depth L suitable for each oilfield. Typically, the geological technicians of each oilfield formulate a reasonable submersion depth L based on their specific circumstances. f后 .

[0053] Step 301: Determine the operating frequency f 后上 Does it exceed the upper limit frequency f of the motor output? 上 The preferred upper limit frequency f of the motor output in this embodiment is preferred. 上 The range is between 61Hz and 80Hz.

[0054] Step 302: When f 后上 <f 上 Then according to the operating frequency f 后上 implement;

[0055] Step 303: When f 后上 ≥f 上 Then according to the operating frequency f 后上 =f 上 implement;

[0056] Step 4: If the conditions for adjusting the stroke rate are not met, then the oil well does not meet the conditions for adjustment.

[0057] According to the operating frequency f 后上 After the system stabilizes, remeasure the daily fluid production, dynamic fluid level, dynamometer card, and input power of the oil well. Calculate the efficiency of the improved system after the well intervention measures to evaluate the application effect. The calculation formula is as follows:

[0058] Application effect = η′ 系后 -η′ 系前 .

[0059] Figure 2 This is a flowchart of the downhole pumping frequency adjustment method according to an embodiment of this disclosure; by Figure 2 As shown: The method for adjusting the number of strokes in a pumping unit well includes the following steps:

[0060] Taking oil well Y1 as an example, the method for adjusting the stroke rate of the pumping unit in this disclosure is applied to adjust the stroke rate. The specific steps are as follows:

[0061] Step 1: Obtain basic data before oil well intervention, including operating frequency f 前 =45Hz, indicator diagram, daily liquid production Q 液前 =32.52t / d, dynamic liquid level h 前 =745m, submersion degree L f前 =255m, surface extracted liquid volume water content f w前 =30% and input power P 前 =7.59kW, calculate the pump fill rate η before well intervention based on the dynamometer card. 泵前 =97%, Improved system efficiency η′ 系前 =25.35%.

[0062] Step 2: Based on the pump filling degree η before the measure = 97% and the submersion degree L f前 =255m, operating frequency f 前 =45Hz while simultaneously satisfying pump fullness η 前 ≥100%, Sinking degree L f前 ≥200m, frequency f 前 ≤50Hz; meets the conditions for increasing the stroke rate.

[0063] Step 3: Meet the conditions for adjusting the number of strokes, and fill the pump to a fullness η. 泵后 Assuming no reduction, set the pump fill level η. 泵后 =85%; with the goal of production under reasonable flow pressure, a reasonable submersion degree L is set according to the conventional technology in this field. f后 =100m, based on the dynamic calculation formula for oil well inflow, predict the daily fluid production after the measures, and calculate the operating frequency f of the parameter adjustment. 后上 =59Hz; the specific calculation formula is as follows:

[0064] P wf (h 前 )=ρ L g(HL)+ρ′ L g(Lh 前 )+P e ;

[0065] P wf (h 后 )=ρ L g(HL)+ρ′ L g(Lh 后 )+P e ;

[0066] L f后 =Lh 后 ;

[0067]

[0068]

[0069]

[0070]

[0071] In the formula, P wf (h 前 ) represents the bottom hole pressure of the oil well before the intervention, in MPa; P wf (h 后 ) represents the bottom hole pressure of the oil well after the treatment, in MPa; the pressure in the middle of the oil reservoir, P. R =11.65 MPa; oil layer mid-depth H = 1450 m; pump hanger depth L = 1000 m; dynamic fluid level depth h after measures 后 =900m; Wellhead casing pressure P e =0.4MPa; Liquid mixing density within the formation ρ L =0.85×10 3 kg / m 3 ; Well fluid density ρ′ L =0.89×10 3 kg / m 3 ; Plunger cross-sectional area A p =0.246×10 -2 m 2 The production coefficient K = 1.08; i 减 The ratio of motor speed to gearbox output shaft speed is 69; the number of motor pole pairs P 极 =8.

[0072] Step 301: Determine the operating frequency f 后上 =59Hz does not exceed the upper limit frequency f of the motor output 上 Set the upper limit frequency f of the motor output. 上 =65Hz;

[0073] Step 302: f 后上 <f 上 Then according to the operating frequency f 后 =Execute at 59Hz;

[0074] Oil well Y1 according to operating frequency f 后上 After the 59Hz operating frequency stabilized, the daily fluid production of the oil well was re-measured as 35.00 t / d, the dynamic fluid level as 904 m, the dynamometer card, the input power as 8.26 kW, and the water cut as 31%. The efficiency of the improved system after the well treatment was calculated to be 34.08%, representing an increase of 8.73 percentage points. The formula used for the calculation is as follows:

[0075] Application effect = η′ 系后 -η′ 系前 =8.73%.

[0076] Example 2

[0077] Taking oil well Y2 as an example, the method for adjusting the pumping unit stroke rate according to the present disclosure is as follows:

[0078] Step 1: Obtain basic data for oil well Y2 before intervention, including operating frequency f. 前 =50Hz, indicator diagram, daily liquid production Q 液前 =24.26m 3 、Dynamic liquid level h 前 =904m, submersion degree L f前 =91.4m, surface extracted liquid volume water content f w前 =25% and input power P 前 =12.38kW, calculate the pump fill rate η before well intervention based on the dynamometer card. 泵前 =11%, Improved system efficiency η′ 系前 =14.78%.

[0079] Step 2: Based on the pump fullness η before the measures are taken 前 =11%, Sinking degree L f前 =91.4m and operating frequency f 前 =50Hz data, and simultaneously satisfy whether the fullness η is satisfied. 泵前 <60% and submersion degree L f前 <200m, operating frequency f 前 The condition for reducing the stroke rate to >30Hz is met; the condition for reducing the stroke rate is met.

[0080] Step 3: When the conditions for reducing the number of strokes are met before the measure, the daily liquid production Q before and after the measure is used as the reference. 液后 The premise is to maintain efficiency while aiming to improve system efficiency; based on the parameter adjustment formula, the pump η is adjusted according to the measures. 泵后 =85%, calculate the operating frequency f of the oil well down-adjustment parameters. 后下 =6.5Hz; the specific calculation formula and process are as follows:

[0081] Q 液前 =Q 液后 ;

[0082]

[0083] η 泵前 ×f 前 =η 泵后 ×f 后下 ;

[0084] f 后下 =η 泵前 ×f 前 / η 泵后 10 3 kg / m 3 ; Plunger cross-sectional area A p =0.246×10 -2 m 2 The production coefficient K = 1.08; i 减 The ratio of motor speed to gearbox output shaft speed is 69; the number of motor pole pairs P 极 =8.

[0085] Step 301: Determine the operating frequency f 后上 =59Hz does not exceed the upper limit frequency f of the motor output 上 Set the upper limit frequency f of the motor output. 上 =65Hz;

[0086] Step 302: f 后上 <f 上 Then according to the operating frequency f 后 =Execute at 59Hz;

[0087] Oil well Y1 according to operating frequency f 后上 After the 59Hz operating frequency stabilized, the daily fluid production of the oil well was re-measured as 35.00 t / d, the dynamic fluid level as 904 m, the dynamometer card, the input power as 8.26 kW, and the water cut as 31%. The efficiency of the improved system after the well treatment was calculated to be 34.08%, representing an increase of 8.73 percentage points. The formula used for the calculation is as follows:

[0088] Application effect = η′ 系后 -η′ 系前 =8.73%.

[0089] Example 2

[0090] Taking oil well Y2 as an example, the method for adjusting the pumping unit stroke rate according to the present disclosure is as follows:

[0091] Step 1: Obtain basic data for oil well Y2 before intervention, including operating frequency f. 前 =50Hz, indicator diagram, daily liquid production Q 液前 =24.26m 3 、Dynamic liquid level h 前 =904m, submersion degree L f前 =91.4m, surface extracted liquid volume water content f w前 =25% and input power P 前 =12.38kW, calculate the pump fill rate η before well intervention based on the dynamometer card. 泵前=11%, Improved system efficiency η′ 系前 =14.78%.

[0092] Step 2: Based on the pump fullness η before the measures are taken 前 =11%, Sinking degree L f前 =91.4m and operating frequency f 前 =50Hz data, and simultaneously satisfy whether the fullness η is satisfied. 泵前 <60% and submersion degree L f前 <200m, operating frequency f 前 The condition for reducing the stroke rate to >30Hz is met; the condition for reducing the stroke rate is met.

[0093] Step 3: When the conditions for reducing the number of strokes are met before the measure, the daily liquid production Q before and after the measure is used as the reference. 液后 The premise is to maintain efficiency while aiming to improve system efficiency; based on the parameter adjustment formula, the pump η is adjusted according to the measures. 泵后 =85%, calculate the operating frequency f of the oil well down-adjustment parameters. 后下 =6.5Hz; the specific calculation formula and process are as follows:

[0094] Q 液前 =Q 液后 ;

[0095]

[0096] η 泵前 ×f 前 =η 泵后 ×f 后下 ;

[0097] f 后下 =η 泵前 ×f 前 / η 泵后 .

Claims

1. A method for adjusting the stroke rate of a pumping unit well, comprising adjusting the stroke rate upwards and downwards; characterized in that: Determine whether the pumping well meets the conditions for increasing or decreasing the stroke rate; If the above conditions for increasing the stroke frequency are met, calculate the operating frequency f of the pumping unit well. 后上 Determine the operating frequency f of the adjusted parameter. 后上 Does it exceed the upper limit frequency f of the motor output? 上 When f 后上 <f 上 Execute the above-mentioned upward adjustment of the operating frequency f 后上 When f 后上 ≥f 上 Execute the upper limit frequency f of the motor output. 上 If the conditions for increasing the stroke rate are not met, no adjustment for increasing the stroke rate will be made for the pumping well. If the conditions for reducing the number of strokes are met, calculate the reduced operating frequency f of the pumping unit well. 后下 Determine the reduced operating frequency f. 后下 Does it exceed the lower limit frequency f of the motor output? 下 When f 后下 ≥f 下 Execute the down-adjustment parameter operating frequency f 后下 When f 后下 <f 下 Execute the lower limit frequency f of the motor output 下 If the conditions for reducing the stroke rate are not met, no adjustment for reducing the stroke rate will be made for the pumping well. The pumping unit well's upward-adjusted operating frequency f 后上 The calculation method is as follows: Set a reasonable submersion level L f后 Calculate the depth h of the dynamic liquid level after the measure. 后 Based on the dynamic calculation formula for oil well inflow, the daily fluid production Q after the measures are predicted. 液后 After setting the measures, the pump fill degree η 泵后 Calculate the operating frequency f of the pumping unit well. 后上 ; The formula for the calculation is: In the formula, Q 液后 The daily liquid production after the measures, m 3 / d;A p Let m be the cross-sectional area of ​​the plunger. 2 K is the production coefficient; i 减 P is the ratio of the motor speed to the output shaft speed of the gearbox; 极 The number of pole pairs of the motor; the pump fill degree η after the measures. 泵后 ,%; The lowered operating frequency f of the pumping unit well 后下 The calculation formula is: f 后下 =the 泵前 ×f 前 / or 泵后 ; In the formula, η 泵前 f represents the pump fill level before the measure. 前 This refers to the operating frequency.

2. The method for adjusting the pumping frequency of an oil well according to claim 1, characterized in that: Obtain the submersion L of the pumping well before the measures. f前 and operating frequency f 前 Data, using indicator diagrams to calculate the pump fill degree η before the measures. 前 According to the pump fill degree η 前 Sinking degree L f前 and operating frequency f 前 The data is used to determine whether the pumping well meets the conditions for increasing or decreasing the stroke rate.

3. The method for adjusting the pumping frequency of an oil well according to claim 2, characterized in that: The pump fill level η before the oil pumping well measures 前 It equals the quotient of the effective stroke of the plunger before the action and the total stroke of the plunger.

4. The method for adjusting the pumping frequency of an oil well according to any one of claims 1-3, characterized in that: The condition for adjusting the stroke rate is that the pump fullness η is simultaneously satisfied. 前 ≥95%, Sinking degree L f前 ≥200m and operating frequency f 前 ≤50Hz; The condition for reducing the number of strokes is that the pump fullness η is satisfied simultaneously. 前 <60%, Submersion degree L f前 <200m and operating frequency f 前 >30Hz.

5. The method for adjusting the pumping frequency of an oil well according to claim 4, characterized in that: The upper limit frequency f of the motor output 上 The lower limit frequency f of the motor output is in the range of 61Hz to 80Hz. 下 The range is between 10Hz and 29Hz. The ratio of motor speed to gearbox output shaft speed; P 极 η represents the number of pole pairs of the motor; η represents the pump fill degree. 泵后 ,%.

6. The method for adjusting the pumping unit stroke frequency according to any one of claims 1-3 or 5, characterized in that, The daily liquid production Q after the measures 液后 The prediction formula is: In the formula, Q 液前 The amount of liquid produced the day before the measure; P wf (h 前 ) represents the bottom hole pressure of the oil well before the intervention, in MPa; P wf (h 后 ) represents the bottom hole pressure of the oil well after the treatment, in MPa; P R This represents the pressure in the middle of the oil reservoir, in MPa.

7. The method for adjusting the pumping frequency of an oil well according to claim 6, characterized in that: The formula for calculating the bottom hole pressure of the oil well before the aforementioned measures is: P wf (h 前 )=ρ L g(H-L)+ρ′ L g(L-h 前 )+P e ; The formula for calculating the bottom hole pressure of the oil well after the aforementioned measures is: P wf (h 后 )=ρ L g(H-L)+ρ′ L g(L-h 后 )+P e ; In the formula, H is the depth of the middle part of the oil layer, m; L is the pumping depth, m; h 后 h represents the depth of the dynamic liquid level after the measures are taken. 后 =LL f后 ,m;P e Wellhead casing pressure, MPa; The density of the liquid mixture within the formation, kg / m³ 3 ;ρ′ L The density of the fluid in the well is kg / m³. 3 .

8. The method for adjusting the pumping unit stroke rate according to claim 6 or 7, characterized in that: After the measures, the pump fill degree η 泵后 The setting range is between 80% and 90%.

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