A fracturing unit displacement intelligent distribution method and system for oilfield fracturing operation

Abstract

The application discloses an oil field fracturing operation fracturing unit displacement intelligent distribution method and system, belongs to the fracturing operation technical field, wherein the oil field fracturring operation fracturing unit displacement intelligent distribution method comprises setting the output displacement of fracturing operation;Select the distribution mode, the distribution mode includes green mode and economic mode;The output displacement is distributed in the fracturing equipment in the electric drive fracturing unit and the diesel drive fracturring unit based on the selected distribution mode.Through personalized selection of displacement distribution mode, which is different from the traditional average distribution mode of construction displacement according to the number of fracturing pump groups in the group, the displacement of each pump injection equipment can be intelligently distributed in combination with actual working conditions and equipment load conditions, and uneven distribution of equipment load is effectively avoided.

Description

Technical Field

[0001] This application belongs to the field of fracturing operation technology, and specifically relates to a method and system for intelligent allocation of fracturing unit displacement in oilfield fracturing operations. Background Technology

[0002] Since the shale gas revolution, horizontal well volumetric fracturing has been widely adopted, with fracturing operations producing "tens of thousands of cubic meters of fluid and thousands of cubic meters of sand" becoming the norm. To maximize production capacity in the shortest possible time, shale oil blocks employ bridge plug perforation technology for reservoir stimulation. Driven by factors such as improving on-site stimulation efficiency and reducing single-well operating costs, horizontal well reservoir stimulation work now utilizes factory-style, zipper-like fracturing operations. "Long cycle, large fluid volume, and fast pace" are among the most significant characteristics of factory-style horizontal well fracturing operations. Due to the advantages of electric fracturing equipment such as small size, low energy consumption, and high power, it is now widely used in major oilfields. Currently, most oilfields employ a combined operation mode of electric and diesel fracturing equipment.

[0003] The current automatic displacement allocation method for fracturing equipment involves first grouping the fracturing pump sets participating in the automatic displacement allocation operation; then, after the operational displacement is input, the system will evenly distribute the operational displacement according to the number of fracturing pump sets within the group. However, due to the different actual operating conditions of each pumping unit (effective output horsepower, fracturing pump head plunger size, etc.), the load distribution of the equipment is uneven, which in turn affects the equipment life and safety. Therefore, research on intelligent displacement allocation methods for fracturing units is of great significance for improving operator efficiency and work quality, reducing construction costs, and ensuring equipment and personnel safety. Summary of the Invention

[0004] The purpose of this invention is to provide an intelligent method for allocating the discharge capacity of fracturing units in oilfield fracturing operations, so as to solve the shortcomings of the discharge capacity allocation in existing fracturing operations mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an intelligent allocation method for the displacement of fracturing units in oilfield fracturing operations, wherein the fracturing units include electric-driven fracturing units and diesel-driven fracturing units, as described above. Figure 1 The allocation methods include: Set the output displacement for fracturing operations; Choose an allocation method, which includes a green mode and an economic mode; The output displacement is allocated among the fracturing equipment in the electric and diesel-driven fracturing units based on the selected allocation method, and includes: In the green mode, the overall load of the electric fracturing unit is increased to the maximum load capacity of the power grid, the maximum load of the power grid is weighted and allocated to each electric fracturing unit, and the remaining displacement is weighted and allocated to the fracturing equipment in each diesel fracturing unit based on the maximum output horsepower of the fracturing equipment in the diesel fracturing unit.

[0006] Preferably, the allocation of the output displacement between the electric-driven fracturing unit and the diesel-driven fracturing unit based on the selected allocation method further includes: Under the economic model, the displacement of the electric-driven fracturing unit and the diesel-driven fracturing unit is adjusted based on the average operating cost of the fracturing equipment.

[0007] Preferably, adjusting the displacement of the electric-driven fracturing unit and the diesel-driven fracturing unit based on the average operating cost of the fracturing equipment includes: Construct a formula for the average cost of fracturing equipment based on the displacement of fracturing equipment; The displacement of the fracturing equipment is adjusted based on the aforementioned average cost formula to reduce the average operating cost of the fracturing equipment.

[0008] Preferably, the average cost formula for the fracturing equipment is: F(a1,a2,a3….an,b1,b2,b3…bm)=(Va1+ Va2+ Va3+…+ Van+ Vb1+ Vb2+ Vb3+…+ Vbm) / (m+n); In the formula, n represents the electric drive equipment number, m represents the diesel drive equipment number, a represents the allocated displacement of the electric drive equipment (m³ / min), b represents the allocated displacement of the diesel drive equipment (m³ / min), Va represents the operating cost of a single electric drive equipment (yuan), Vb represents the operating cost of a single diesel drive equipment (yuan), and F represents the average operating cost of the fracturing equipment (yuan).

[0009] Preferably, the formula for calculating the operating cost of a single electric drive unit is as follows: Va = (Ha) Ga K) / (60) a) + {(1 + Ha)} (r1 / t1+r2 / t2+……rx / tx+o / q)} / 60 a In the formula, Ha represents the ratio of the real-time output water horsepower of the electric drive equipment to the rated output water horsepower, Ga represents the rated power consumption of the electric drive equipment in kilowatt-hours, K is the current electricity price in yuan per kilowatt-hour, x represents the number of the consumable parts in the electric drive equipment, r represents the unit price of the consumable parts in yuan each, t represents the theoretical service time of the consumable parts of the electric drive equipment in hours, o represents the price required for one maintenance of the electric drive equipment in yuan each time, and q represents the maintenance cycle of the electric drive equipment in hours each time.

[0010] The preferred formula for calculating the operating cost of a single diesel-driven unit is as follows: Vb = (Hb) Gb J) / (60) b) + {(1+Hb)} (R1 / T1+R2 / T2+……Ry / Ty+O / Q)} / 60 b In the formula, Hb represents the ratio of the real-time output water horsepower of the diesel-driven equipment to the rated output water horsepower; Gb represents the rated power consumption of the diesel-driven equipment in liters per hour; J indicates the current diesel price in yuan per liter; y represents the number of the wear parts in the diesel-driven equipment; R represents the unit price of the wear parts in yuan each; T represents the theoretical service life of the wear parts in the diesel-driven equipment in hours; O represents the price required for one maintenance of the diesel-driven equipment in yuan each time; and Q represents the maintenance cycle of the diesel-driven equipment in hours each time.

[0011] Preferably, the real-time output water horsepower of the electric drive equipment is the product of the current construction pressure, the real-time displacement of the electric drive equipment, and 22.34, and the real-time output water horsepower of the diesel drive equipment is the product of the current construction pressure, the real-time displacement of the diesel drive equipment, and 22.34.

[0012] Preferably, the allocation method further includes: The fracturing equipment of the electric-driven fracturing unit and the diesel-driven fracturing unit are numbered, and the numbered fracturing equipment is connected to the same control system.

[0013] This application also discloses an intelligent displacement allocation system for fracturing units in oilfield fracturing operations, wherein the fracturing units include electric-driven fracturing units and diesel-driven fracturing units, and the allocation system includes: The configuration module is used to set the output displacement of fracturing operations; The selection module is configured to select an allocation method, which includes a green mode and an economic mode. A distribution module, configured to distribute the output displacement between electric-driven fracturing units and diesel-driven fracturing units based on a selected distribution method, includes: In the green mode, the overall load of the electric fracturing unit is increased to the maximum load capacity of the power grid, the maximum load of the power grid is weighted and allocated to each electric fracturing unit, and the remaining displacement is weighted and allocated to each diesel fracturing unit based on the maximum output horsepower of the diesel fracturing equipment.

[0014] Preferably, the allocation module is further configured to: Under the aforementioned economic model, the displacement of the electric-driven fracturing unit and the diesel-driven fracturing unit is adjusted based on the real-time operating cost of the fracturing equipment.

[0015] Compared with the prior art, the beneficial effects of the present invention are: This application, through personalized displacement allocation, differs from the traditional method of evenly distributing the construction displacement based on the number of fracturing pump sets within a group. It can intelligently allocate the displacement of each pumping device by combining actual working conditions and equipment load, effectively avoiding uneven equipment load distribution, ensuring equipment safety, and can switch between green and economic modes, thus improving the green operation of fracturing. Attached Figure Description

[0016] Figure 1 A flowchart of the allocation method for this application; Figure 2 This is a schematic diagram of the allocation system for this application. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] A method for intelligently allocating the displacement of fracturing units in oilfield fracturing operations (hereinafter referred to as the allocation method), wherein the fracturing units include electric-driven fracturing units and diesel-driven fracturing units, and the allocation method includes the following steps: S100: Sets the output displacement for fracturing operations; S200: Select an allocation method, which includes a green mode and an economic mode, wherein in the green mode; S300: Distributing the output displacement among fracturing equipment in electric and diesel-driven fracturing units based on the selected distribution method, and including: In the green mode, the overall load of the electric fracturing unit is increased to the maximum load capacity of the power grid, the maximum load of the power grid is weighted and allocated to each electric fracturing unit, and the remaining displacement is weighted and allocated to the fracturing equipment in each diesel fracturing unit based on the maximum output horsepower of the fracturing equipment in the diesel fracturing unit.

[0019] The allocation method further includes: The fracturing equipment of the electric-driven fracturing unit and the diesel-driven fracturing unit are numbered, and the numbered fracturing equipment is connected to the same control system.

[0020] In this step, the numbered fracturing equipment is connected to the same control system (e.g., a PLC system). By integrating the communication protocols of the fracturing equipment in diesel-driven and electric-driven fracturing units, the control of the fracturing equipment in both units is integrated onto the same operating platform. A user-friendly interface is designed to allow operators to easily monitor and control different types of fracturing equipment (i.e., electric-driven and diesel-driven fracturing units). This improves the compatibility and stability of the operation of electric and diesel-driven fracturing units, achieving simultaneous control of fracturing equipment in both units and effectively enhancing the timeliness and safety of fracturing unit operation.

[0021] In some embodiments, in step S300, under green mode, the fracturing equipment in the electric fracturing unit is preferentially selected for operation. That is, when the grid load allows, the displacement of the fracturing equipment (hereinafter referred to as electric fracturing equipment) in the electric fracturing unit is preferentially increased. In other words, the displacement allocation of the electric fracturing equipment is related to its own maximum output horsepower. When the maximum displacement of the electric fracturing unit cannot reach the output displacement, the diesel fracturing unit is started to allocate the remaining displacement to achieve full utilization of the electric fracturing unit. Specifically, in some embodiments, the allocation of the remaining displacement in the fracturing equipment (hereinafter referred to as diesel fracturing equipment) in the diesel fracturing unit is achieved by weighting the maximum output horsepower of the fracturing equipment in the diesel fracturing unit. That is, the displacement allocation of the diesel fracturing equipment is related to its own maximum output horsepower to ensure that each diesel fracturing equipment can operate in the best condition.

[0022] In some embodiments, when the allocation method is selected as the economic mode, the displacement of the electric fracturing unit and the diesel fracturing unit is adjusted based on the average operating cost of the fracturing equipment (including the electric drive equipment constituting the electric fracturing unit and the diesel drive equipment constituting the diesel fracturing unit). Specifically, in some embodiments, the displacement adjustment of the fracturing equipment includes: Construct an average cost formula for fracturing equipment based on the displacement of each fracturing unit; The displacement of each fracturing device is adjusted based on the average cost formula to reduce the average operating cost of the fracturing equipment.

[0023] The displacement of the aforementioned electric-driven and diesel-driven fracturing units is adjusted based on the cost calculation formula for fracturing equipment. Specifically, the cost calculation formula for fracturing equipment is as follows: F(a1,a2,a3….an,b1,b2,b3…bm)=(Va1+ Va2+ Va3+…+ Van+ Vb1+ Vb2+ Vb3+…+ Vbm) / (m+n); In the above formula, n represents the electric drive equipment number, m represents the diesel drive equipment number, a represents the allocated displacement of the electric drive equipment in m³ / min, b represents the allocated displacement of the diesel drive equipment in m³ / min, Va represents the operating cost of a single electric drive equipment in yuan, Vb represents the operating cost of a single diesel drive equipment in yuan, and F represents the average operating cost of the fracturing equipment in yuan. The formula for calculating Va is as follows: Va = (Ha) Ga K) / (60) a) + {(1 + Ha)} (r1 / t1+r2 / t2+……rx / tx+o / q)} / 60 a In the formula, Ha represents the ratio of the real-time output water horsepower of the electric drive equipment to its rated output water horsepower. The real-time output water horsepower of the electric drive equipment is the product of the current construction pressure, the real-time displacement of the electric drive equipment, and 22.34. Specifically, taking a rated horsepower of 5000 hhp as an example, the calculation formula for Ha is Ha = (P a 22.34) / 5000, where P represents the current construction pressure in MPa, Ga represents the rated power consumption of the electric drive equipment in kilowatt-hours, K is the current electricity price in yuan per kilowatt-hour, x represents the number of the wear-resistant component in the electric drive equipment, r represents the unit price of the wear-resistant component in yuan each, t represents the theoretical service time of the wear-resistant component in the electric drive equipment in hours, o represents the price required for one maintenance of the electric drive equipment in yuan each time, and q represents the maintenance cycle of the electric drive equipment in hours each time; The formula for calculating Vb is as follows: Vb = (Hb) Gb J) / (60) b) + {(1+Hb)} (R1 / T1+R2 / T2+……Ry / Ty+O / Q)} / 60 b In the formula, Hb represents the ratio of the real-time output water horsepower of the diesel-driven equipment to its rated output water horsepower. The real-time output water horsepower of the diesel-driven equipment is the product of the current construction pressure, the real-time displacement of the diesel-driven equipment, and 22.34. Specifically, taking a rated output horsepower of 2500 hhp as an example, the formula for calculating Hb is Hb = (P b 22.34) / 2500, where P represents the construction pressure in MPa, b represents the current real-time output displacement of the diesel-driven equipment in cubic meters per minute, J indicates the current diesel price in yuan per liter, Gb represents the rated power consumption of the diesel-driven equipment in liters per hour, y represents the number of the wear parts in the diesel-driven equipment, R represents the unit price of the wear parts in yuan per piece, T represents the theoretical service life of the wear parts in the diesel-driven equipment in hours, O represents the price required for one maintenance of the diesel-driven equipment in yuan per maintenance, and Q represents the maintenance cycle of the diesel-driven equipment in hours per maintenance.

[0024] After obtaining the cost calculation formula for the fracturing equipment, since only the allocated displacement of the electric drive equipment and the allocated displacement of the diesel drive equipment are variables in the formula, and the sum of the allocated displacement of the electric drive equipment and the allocated displacement of the diesel drive equipment (i.e., the total allocated displacement) is a set value (i.e., the set displacement), the allocated displacement of each fracturing equipment (i.e., the values ​​of a and b) can be obtained by exhaustive methods, thereby realizing the displacement allocation of the electric drive equipment and the diesel drive equipment.

[0025] Based on the aforementioned cost calculation formula, the displacement of fracturing equipment is adjusted. During displacement allocation, factors such as fuel consumption, electricity consumption, equipment depreciation, and wear of vulnerable parts are fully considered. This achieves personalized displacement allocation based on the specific conditions of the fracturing equipment. Personalized displacement allocation provides on-site commanders with a more flexible fracturing pump control mode, reducing operational costs while ensuring fracturing quality. Simultaneously, the fracturing displacement can be rationally allocated according to the actual operating conditions of each piece of equipment, ensuring balanced displacement among different fracturing units and controlling equipment wear within an average range. By using average power consumption, overall efficiency can be improved, and the service life of the fracturing equipment can be extended.

[0026] This application also discloses an intelligent displacement allocation system for fracturing units in oilfield fracturing operations, wherein the fracturing units include electric-driven fracturing units and diesel-driven fracturing units, and the allocation system includes: The configuration module is used to set the output displacement of fracturing operations; The selection module is configured to select an allocation method, which includes a green mode and an economic mode. A distribution module, configured to distribute the output displacement between electric-driven fracturing units and diesel-driven fracturing units based on a selected distribution method, includes: In the green mode, the overall load of the electric fracturing unit is increased to the maximum load capacity of the power grid, the maximum load of the power grid is weighted and allocated to each electric fracturing unit, and the remaining displacement is weighted and allocated to each diesel fracturing unit based on the maximum output horsepower of the diesel fracturing equipment. And under the economic model, the displacement of the electric-driven fracturing unit and the diesel-driven fracturing unit is adjusted based on the average operating cost of the fracturing equipment.

[0027] In the description of this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this invention, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, those skilled in the art can combine different embodiments or examples and features of different embodiments or examples described in this invention without contradiction.

[0028] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for intelligent allocation of displacement of fracturing unit in oilfield fracturing operations, characterized in that, The fracturing units include electric-driven fracturing units and diesel-driven fracturing units, and the allocation method includes: Set the output displacement for fracturing operations; Choose an allocation method, which includes a green mode and an economic mode; The output displacement is allocated among the fracturing equipment in the electric and diesel-driven fracturing units based on the selected allocation method, and includes: In the green mode, the overall load of the electric fracturing unit is increased to the maximum load capacity of the power grid, the maximum load of the power grid is weighted and allocated to each electric fracturing unit, and the remaining displacement is weighted and allocated to the fracturing equipment in each diesel fracturing unit based on the maximum output horsepower of the fracturing equipment in the diesel fracturing unit. Under the aforementioned economic model, the displacement of the electric-driven fracturing unit and the diesel-driven fracturing unit is adjusted based on the average operating cost of the fracturing equipment. The adjustment of the displacement of the electric-driven fracturing unit and the diesel-driven fracturing unit based on the average operating cost of the fracturing equipment includes: Construct a formula for the average cost of fracturing equipment based on the displacement of fracturing equipment; The displacement of the fracturing equipment is adjusted based on the aforementioned average cost formula to reduce the average operating cost of the fracturing equipment. The formula for the average cost of the fracturing equipment is: F(a1,a2,a3….an,b1,b2,b3…bm)=(Va1+ Va2+ Va3+…+ Van+ Vb1+ Vb2+ Vb3+…+Vbm) / (m+n); In the formula, n represents the electric drive equipment number, m represents the diesel drive equipment number, a represents the allocated displacement of the electric drive equipment in m³ / min, b represents the allocated displacement of the diesel drive equipment in m³ / min, Va represents the operating cost of a single electric drive equipment in yuan, Vb represents the operating cost of a single diesel drive equipment in yuan, and F represents the average operating cost of the fracturing equipment in yuan. The formula for calculating the operating cost of a single electric drive unit is as follows: Va=(Ha Ga K) / (60 a)+{(1+Ha) (r1 / t1+r2 / t2+……rx / tx+o / q)} / 60 a In the formula, Ha represents the ratio of the real-time output water horsepower of the electric drive equipment to the rated output water horsepower, Ga represents the rated power consumption of the electric drive equipment in kilowatt-hours, K is the current electricity price in yuan per kilowatt-hour, x represents the number of the wear-resistant component in the electric drive equipment, r represents the unit price of the wear-resistant component in yuan each, t represents the theoretical service time of the wear-resistant component in the electric drive equipment in hours, o represents the price required for one maintenance of the electric drive equipment in yuan each time, and q represents the maintenance cycle of the electric drive equipment in hours each time; The formula for calculating the operating cost of a single diesel-driven unit is as follows: Vb=(Hb Gb J) / (60 b)+{(1+Hb) (R1 / T1+R2 / T2+……Ry / Ty+O / Q)} / 60 b In the formula, Hb represents the ratio of the real-time output water horsepower of the diesel-driven equipment to the rated output water horsepower; Gb represents the rated power consumption of the diesel-driven equipment in liters per hour; J indicates the current diesel price in yuan per liter; y represents the number of the wear parts in the diesel-driven equipment; R represents the unit price of the wear parts in yuan each; T represents the theoretical service life of the wear parts in the diesel-driven equipment in hours; O represents the price required for one maintenance of the diesel-driven equipment in yuan each time; and Q represents the maintenance cycle of the diesel-driven equipment in hours each time.

2. The intelligent allocation method for fracturing unit displacement in oilfield fracturing operations according to claim 1, characterized in that: The real-time output water horsepower of the electric drive equipment is the product of the current construction pressure, the real-time displacement of the electric drive equipment, and 22.

34. The real-time output water horsepower of the diesel drive equipment is the product of the current construction pressure, the real-time displacement of the diesel drive equipment, and 22.

34.

3. The intelligent allocation method for fracturing unit displacement in oilfield fracturing operations according to claim 1, characterized in that: The allocation method further includes: The fracturing equipment of the electric-driven fracturing unit and the diesel-driven fracturing unit are numbered, and the numbered fracturing equipment is connected to the same control system.

4. An intelligent displacement allocation system for fracturing units in oilfield fracturing operations, characterized in that: The fracturing unit includes an electric fracturing unit and a diesel fracturing unit, and the distribution system includes: The configuration module is used to set the output displacement of fracturing operations; The selection module is configured to select an allocation method, which includes a green mode and an economic mode. A distribution module, configured to distribute the output displacement between electric-driven fracturing units and diesel-driven fracturing units based on a selected distribution method, includes: In the green mode, the overall load of the electric fracturing unit is increased to the maximum load capacity of the power grid, the maximum load of the power grid is weighted and allocated to each electric fracturing unit, and the remaining displacement is weighted and allocated to each diesel fracturing unit based on the maximum output horsepower of the diesel fracturing equipment. Under the aforementioned economic model, the displacement of the electric-driven fracturing unit and the diesel-driven fracturing unit is adjusted based on the average operating cost of the fracturing equipment. The adjustment of the displacement of the electric-driven fracturing unit and the diesel-driven fracturing unit based on the average operating cost of the fracturing equipment includes: Construct a formula for the average cost of fracturing equipment based on the displacement of fracturing equipment; The displacement of the fracturing equipment is adjusted based on the aforementioned average cost formula to reduce the average operating cost of the fracturing equipment. The formula for the average cost of the fracturing equipment is: F(a1,a2,a3….an,b1,b2,b3…bm)=(Va1+ Va2+ Va3+…+ Van+ Vb1+ Vb2+ Vb3+…+Vbm) / (m+n); In the formula, n represents the electric drive equipment number, m represents the diesel drive equipment number, a represents the allocated displacement of the electric drive equipment in m³ / min, b represents the allocated displacement of the diesel drive equipment in m³ / min, Va represents the operating cost of a single electric drive equipment in yuan, Vb represents the operating cost of a single diesel drive equipment in yuan, and F represents the average operating cost of the fracturing equipment in yuan. The formula for calculating the operating cost of a single electric drive unit is as follows: Va=(Ha Ga K) / (60 a)+{(1+Ha) (r1 / t1+r2 / t2+……rx / tx+o / q)} / 60 a In the formula, Ha represents the ratio of the real-time output water horsepower of the electric drive equipment to the rated output water horsepower, Ga represents the rated power consumption of the electric drive equipment in kilowatt-hours, K is the current electricity price in yuan per kilowatt-hour, x represents the number of the wear-resistant component in the electric drive equipment, r represents the unit price of the wear-resistant component in yuan each, t represents the theoretical service time of the wear-resistant component in the electric drive equipment in hours, o represents the price required for one maintenance of the electric drive equipment in yuan each time, and q represents the maintenance cycle of the electric drive equipment in hours each time; The formula for calculating the operating cost of a single diesel-driven unit is as follows: Vb=(Hb Gb J) / (60 b)+{(1+Hb) (R1 / T1+R2 / T2+……Ry / Ty+O / Q)} / 60 b In the formula, Hb represents the ratio of the real-time output water horsepower of the diesel-driven equipment to the rated output water horsepower; Gb represents the rated power consumption of the diesel-driven equipment in liters per hour; J indicates the current diesel price in yuan per liter; y represents the number of the wear parts in the diesel-driven equipment; R represents the unit price of the wear parts in yuan each; T represents the theoretical service life of the wear parts in the diesel-driven equipment in hours; O represents the price required for one maintenance of the diesel-driven equipment in yuan each time; and Q represents the maintenance cycle of the diesel-driven equipment in hours each time.

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