A method for evaluating carbon efficiency of manufacturing processes

Abstract

The present invention discloses a method for evaluating the carbon efficiency of a manufacturing process. First, the system boundary of the manufacturing process is defined, the list of carbon emission sources is analyzed, and the carbon emission sources are classified; then, according to the materials, energy consumption and process information of the manufacturing process, the corresponding generalized characteristic function of the carbon source is defined, and the carbon emission of materials, energy carbon emission, process carbon emission and total carbon emission in the manufacturing process are calculated respectively; finally, combined with the process parameters of the manufacturing process (cutting parameters, workpiece materials, tool parameters, process conditions), the carbon efficiency of the manufacturing process working hours and the carbon efficiency of material removal are defined from the two dimensions of processing hours and material removal, and a calculation model corresponding to the two carbon efficiencies is constructed. On this basis, in order to meet the evaluation of the manufacturing process, combined with the actual situation of the manufacturing process, the carbon efficiency quota of the working hours and the carbon efficiency quota of the material removal are proposed. This method can provide a theoretical method for the evaluation of the carbon efficiency of the manufacturing process and lay a basic support for the subsequent carbon emission reduction of manufacturing enterprises.

Description

Technical Field

[0001] The invention relates to the field of mechanical manufacturing and processing, and in particular to a method for evaluating carbon efficiency of a manufacturing process. Background Art

[0002] Manufacturing is an important part of industry and the cornerstone of the national economy. However, the current manufacturing industry has problems such as high energy consumption and serious emissions. According to statistics from the International Energy Agency (IEA), the global final energy consumption in 2018 was 99.38 billion tons of oil equivalent, an increase of 2.2% year-on-year, of which the total industrial energy consumption accounted for about 1 / 3 of the global energy consumption, and the electricity consumed by the manufacturing industry accounted for about 28% of the total industrial energy consumption. In addition, the global energy-related carbon dioxide emissions were 33.1 GtCO2, an increase of 1.5% year-on-year, of which the carbon dioxide emissions generated in the industrial field were 11.6 GtCO2, accounting for 36% of the global carbon dioxide emissions, and the carbon dioxide emissions from the manufacturing industry accounted for about 41% of the industrial emissions. In 2018, my country's GDP reached 91.9 trillion, of which the scale of manufacturing output was 25.6 trillion, accounting for about 27.8% of the GDP. my country has been a world manufacturing power for many consecutive years, of which energy consumption reached about 20.7 billion tons of oil equivalent and carbon dioxide emissions reached about 9.57 billion tons, ranking first in the world.

[0003] Therefore, in the context of global resource consumption and climate warming, domestic and foreign experts and scholars have conducted a lot of research on carbon emissions in the manufacturing process. However, as an absolute quantity, carbon emissions are difficult to truly reflect the pros and cons of the processing technology, and there is a lack of comparison for different processes and products. In addition, some scholars have proposed carbon efficiency evaluation indicators such as carbon emission utilization rate, production carbon efficiency, and economic carbon efficiency. However, these carbon efficiency indicators focus on the input / output ends of the manufacturing and processing system boundary, and have not yet been combined with the process parameters, tool parameters, and processing status in the manufacturing process. In the actual manufacturing process, carbon emissions have the characteristics of multi-source heterogeneity and dynamic coupling, which leads to the results obtained by using the above carbon efficiency indicators are very rough, and it is difficult to truly reflect the dynamic changes in carbon efficiency in the manufacturing process, and the guiding role for the actual manufacturing process is weak. Summary of the invention

[0004] The purpose of the present invention is to provide a method for evaluating carbon efficiency in a manufacturing process to solve the problems existing in the prior art.

[0005] The technical solution adopted to achieve the purpose of the present invention is as follows: a method for evaluating carbon efficiency of a manufacturing process, comprising the following steps:

[0006] 1) Based on the characteristics of the manufacturing system, define the manufacturing process system boundary and conduct a carbon emission source inventory analysis;

[0007] 2) Classify the carbon emission sources in the manufacturing process according to the characteristics of the carbon emission sources. At the same time, define the corresponding generalized characteristic function of the carbon source according to the materials, energy consumption and process information of the manufacturing process, and establish the material carbon emission, energy carbon emission, process carbon emission and total carbon emission models of the manufacturing process;

[0008] 3) Combining the manufacturing process parameters, from the two dimensions of processing time and material removal, define the manufacturing process time carbon efficiency and material removal carbon efficiency, and establish their calculation models respectively;

[0009] 4) Based on the actual situation of the manufacturing process, the carbon efficiency quota of working hours and the carbon efficiency quota of material removal are proposed.

[0010] Furthermore, the manufacturing process parameters in step 3) include cutting parameters, workpiece materials, tool parameters and process conditions.

[0011] Further, in step 2), the material carbon emission refers to the carbon emission generated in the material production process, the material includes raw materials and auxiliary materials, the auxiliary materials include cutting fluid and lubricating fluid, and the material carbon generalized characteristic function is:

[0012]

[0013] in: is the generalized characteristic function of carbon source of carbon emission of the i-th material, which represents the consumption of the i-th material in this process; is the carbon emission characteristic function of raw materials, ρ1 is the density of raw materials, and x1 is the volume of raw materials; is the tool carbon emission characteristic function, ρ2 is the tool material density, and x2 is the tool material consumption volume converted in this process; is the carbon emission characteristic function of the cutting fluid, x3 is the average amount of cutting fluid consumed in the process during the use period of the cutting fluid; is the carbon emission characteristic function of the lubricant, x4 is the average amount of lubricant consumed by the process during the lubricant life cycle;

[0014] Energy carbon emissions refer to the carbon emissions generated by various energy sources consumed in the production process. The generalized characteristic function of energy carbon is:

[0015]

[0016] in: is the generalized characteristic function of carbon source of the j-th energy source carbon emission, which represents the consumption of the j-th energy source in the process; is the carbon emission characteristic function of electric energy, P sb is the standby power of the equipment during the manufacturing process, P idleis the no-load power of the equipment, P cut is the cutting power of the equipment, t sb ,t idle and y1 are the equipment standby time, equipment idle time and cutting time respectively; is the carbon emission characteristic function of compressed air, y2 is the volume of compressed air consumption; is the tap water carbon emission characteristic function, y3 is the tap water consumption volume;

[0017] The process carbon emissions refer to the carbon emissions generated by fuel combustion, chemical interactions between auxiliary materials, and post-processing of chips, waste cutting oil, and waste tools during the production process. The generalized characteristic function of process carbon is:

[0018]

[0019] in: is the generalized characteristic function of the carbon source of the kth direct emission or waste carbon emission, which represents the amount of the kth direct emission or waste of the process; is the carbon emission characteristic function of the waste chips to be processed, z1 is the amount of waste chips to be processed; is the carbon emission characteristic function of the waste cutting fluid to be treated for this process, z2 is the amount of waste cutting fluid to be treated; The carbon emission characteristic function of the worn waste tools to be processed is converted for this process, and z3 is the amount of waste tools to be processed.

[0020] Furthermore, in step 2), the calculation formulas for material carbon emissions, energy carbon emissions, process carbon emissions and total carbon emissions during the manufacturing process are as follows:

[0021] Material Carbon Emissions:

[0022]

[0023] Among them: CE m Carbon emissions from materials during the manufacturing process, is the carbon emission coefficient corresponding to the i-th material;

[0024] Energy Carbon Emissions:

[0025]

[0026] Among them: CE r Energy carbon emissions during the manufacturing process, is the carbon emission coefficient of the j-th energy source;

[0027] Process carbon emissions:

[0028]

[0029] Among them: CE p Carbon emissions from the manufacturing process. is the carbon emission coefficient of the kth direct emission / waste;

[0030] Total Carbon Emissions:

[0031]

[0032] Further, in step 3), the man-hour carbon efficiency represents the carbon emissions generated by the manufacturing process per unit time. During the manufacturing process, the equipment has different operating states, including standby, no-load and processing. The man-hour carbon efficiency reflects the changes in carbon emissions of the manufacturing process in the time dimension. The man-hour carbon efficiency calculation formula is as follows:

[0033]

[0034] Where: T is the time consumed by the process;

[0035] The material removal carbon efficiency represents the carbon emissions generated by removing a unit volume of material. During the cutting process, the material removal carbon efficiency reflects the changes in carbon emissions in the manufacturing process in the volume dimension. The material removal carbon efficiency calculation formula is as follows:

[0036]

[0037] Where: V is the volume of workpiece material removed in this process, MRR is the material removal rate, and the material removal rate represents the amount of material removed per unit time in the manufacturing process;

[0038] The material removal rate calculation formula is:

[0039]

[0040] Where: ΔV is the volume change of the material per unit time, F(v C ,f,a p ,...) is the material removal characteristic function, v c is the cutting speed, f is the feed rate, a p The amount of knife damage on the back.

[0041] Further, in step 4), the man-hour carbon efficiency quota is the average man-hour carbon efficiency obtained by processing n identical workpieces in the process, and the calculation formula is as follows:

[0042]

[0043]

[0044] Where: T iis the time consumed in processing the i-th workpiece in this process, STC i The carbon efficiency of the man-hour calculated for processing the i-th workpiece, The carbon efficiency quota for the man-hours of the process;

[0045] The material removal carbon efficiency quota is the average value of the material removal carbon efficiency obtained by processing n identical workpieces in this process, and the calculation formula is as follows:

[0046]

[0047]

[0048] Where: V strat is the volume of the workpiece before processing, V end STC is the volume of the workpiece after processing. i The material removal carbon efficiency calculated for machining the i-th workpiece, Provides a carbon removal efficiency quota for the material in the process.

[0049] The beneficial effects of the present invention are:

[0050] 1. Aiming at the characteristics of multi-source heterogeneity and dynamic coupling of carbon emissions in the manufacturing process, the present invention combines the process parameters of the manufacturing process, defines two evaluation indicators, namely, carbon efficiency of processing hours and material volume removal, and proposes a manufacturing process carbon efficiency evaluation method, which overcomes the shortcomings of the prior art of rough carbon emission calculation and inaccurate carbon efficiency model, and realizes the dynamic calculation and quota management of carbon efficiency in the manufacturing process;

[0051] 2. The generalized characteristic function of carbon source and material removal characteristic function defined in the present invention have wide adaptability, strong scalability and transplantability, can be applied to different processing technologies, avoid the limitations of traditional methods, and facilitate the development of carbon efficiency evaluation system in the later manufacturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 Specific steps for the carbon efficiency evaluation method of the manufacturing process;

[0053] Figure 2 Define carbon emission boundaries for manufacturing processes;

[0054] Figure 3 Analyze the carbon emission source inventory and classify carbon emission sources for the manufacturing process;

[0055] Figure 4 How to obtain carbon emission data for the manufacturing process;

[0056] Figure 5 The size of a shaft-type workpiece to be turned;

[0057] Figure 6 This is the system boundary and carbon source list for the manufacturing process of turning a shaft workpiece. DETAILED DESCRIPTION

[0058] The present invention is further described below in conjunction with the embodiments, but it should not be understood that the above subject matter of the present invention is limited to the following embodiments. Without departing from the above technical ideas of the present invention, various substitutions and changes are made according to the common technical knowledge and customary means in the art, which should all be included in the protection scope of the present invention.

[0059] Embodiment 1:

[0060] See also Figure 1 This embodiment discloses a method for evaluating carbon efficiency of a manufacturing process, comprising the following steps:

[0061] 1) Based on the characteristics of the manufacturing system, define the manufacturing process system boundary and conduct a carbon emission source inventory analysis; see Figure 2 , defines the carbon emission boundary for the manufacturing process;

[0062] 2) See Figure 3 , based on the characteristics of carbon emission sources, the carbon emission sources in the manufacturing process are classified, and based on the materials, energy consumption and process information of the manufacturing process, the corresponding generalized characteristic functions of carbon sources are defined, and the material carbon emission, energy carbon emission, process carbon emission and total carbon emission models of the manufacturing process are established; see Figure 4 , is a method for obtaining carbon emission data in the manufacturing process; wherein, the material carbon emission refers to the carbon emission generated in the material production process, the material includes raw materials and auxiliary materials, the auxiliary materials include cutting fluid and lubricating fluid, and the material carbon generalized characteristic function is:

[0063]

[0064] in: is the generalized characteristic function of carbon source of carbon emission of the i-th material, which represents the consumption of the i-th material in this process; is the carbon emission characteristic function of raw materials, ρ1 is the density of raw materials, and x1 is the volume of raw materials; is the tool carbon emission characteristic function, ρ2 is the tool material density, and x2 is the tool material consumption volume converted in this process; is the carbon emission characteristic function of the cutting fluid, x3 is the average amount of cutting fluid consumed in the process during the use period of the cutting fluid; is the carbon emission characteristic function of the lubricating fluid, x4 is the average amount of lubricating fluid consumed by the process during the lubricating fluid use cycle; the generalized carbon characteristic function of the material can be expanded according to the carbon source in the specific manufacturing process;

[0065] Energy carbon emissions refer to the carbon emissions generated by various energy sources consumed in the production process. The generalized characteristic function of energy carbon is:

[0066]

[0067] in: is the generalized characteristic function of carbon source of the j-th energy source carbon emission, which represents the consumption of the j-th energy source in the process; is the carbon emission characteristic function of electric energy, P sb is the standby power of the equipment during the manufacturing process, P idle is the no-load power of the equipment, P cut is the cutting power of the equipment, t sb ,t idle and y1 are the equipment standby time, equipment idle time and cutting time respectively; is the carbon emission characteristic function of compressed air, y2 is the volume of compressed air consumption; is the tap water carbon emission characteristic function, y3 is the tap water consumption volume; the energy carbon generalized characteristic function can be expanded according to the carbon source in the specific manufacturing process;

[0068] The process carbon emissions refer to the carbon emissions generated by fuel combustion, chemical interactions between auxiliary materials, and post-processing of chips, waste cutting oil, and waste tools during the production process. The generalized characteristic function of process carbon is:

[0069]

[0070] in: is the generalized characteristic function of the carbon source of the kth direct emission or waste carbon emission, which represents the amount of the kth direct emission or waste of the process; is the carbon emission characteristic function of the waste chips to be processed, z1 is the amount of waste chips to be processed; is the carbon emission characteristic function of the waste cutting fluid to be treated for this process, z2 is the amount of waste cutting fluid to be treated; The carbon emission characteristic function of the worn waste tools to be processed is converted for this process, and z3 is the amount of the waste tools to be processed; the generalized characteristic function of process carbon can be expanded according to the carbon source in the specific manufacturing process;

[0071] The calculation formulas for material carbon emissions, energy carbon emissions, process carbon emissions and total carbon emissions during the manufacturing process are as follows:

[0072] Material Carbon Emissions:

[0073]

[0074] Among them: CE mCarbon emissions from materials during the manufacturing process, is the carbon emission coefficient corresponding to the i-th material;

[0075] Energy Carbon Emissions:

[0076]

[0077] Among them: CE r Energy carbon emissions during the manufacturing process, is the carbon emission coefficient of the j-th energy source;

[0078] Process carbon emissions:

[0079]

[0080] Among them: CE p Carbon emissions from the manufacturing process. is the carbon emission coefficient of the kth direct emission / waste;

[0081] Total Carbon Emissions:

[0082]

[0083] 3) In combination with the process parameters of the manufacturing process, the manufacturing process carbon efficiency and material removal carbon efficiency are defined from the two dimensions of processing time and material removal, and their calculation models are established respectively; the manufacturing process process parameters include cutting parameters, workpiece materials, tool parameters and process conditions; wherein, the carbon efficiency of the working hours represents the carbon emissions generated by the manufacturing process per unit time. During the manufacturing process, the equipment has different operating states, including standby, no-load and processing. The carbon efficiency of the working hours reflects the changes in carbon emissions of the manufacturing process in the time dimension. The calculation formula of the carbon efficiency of the working hours is as follows:

[0084]

[0085] Where: T is the time consumed by the process;

[0086] The material removal carbon efficiency represents the carbon emissions generated by removing a unit volume of material. During the cutting process, material removal changes gradually. The material removal carbon efficiency reflects the changes in carbon emissions in the manufacturing process in the volume dimension. The material removal carbon efficiency calculation formula is as follows:

[0087]

[0088] Where: V is the volume of workpiece material removed in this process, MRR is the material removal rate, and the material removal rate indicates the amount of material removed per unit time in the manufacturing process. It is related to the machining process parameters and tool parameters, and the calculation formula of the material removal rate corresponding to different machining processes is different;

[0089] The material removal rate calculation formula is:

[0090]

[0091] Where: ΔV is the change of workpiece material per unit time, F(v C ,f,a p ,...) is the material removal characteristic function, v c is the cutting speed, f is the feed rate, a p To eat knife quantity for back;

[0092] 4) In order to meet the evaluation of manufacturing process, combined with the actual situation of the manufacturing process, the man-hour carbon efficiency quota and material removal carbon efficiency quota are proposed:

[0093] In order to quantitatively evaluate the carbon emissions generated in the complete manufacturing process of a certain process from the time dimension, a man-hour carbon efficiency quota is proposed. The man-hour carbon efficiency quota is the average man-hour carbon efficiency obtained by processing n identical workpieces in the process. The calculation formula is as follows:

[0094]

[0095]

[0096] Where: T i is the time consumed in processing the i-th workpiece in this process, STC i The carbon efficiency of the man-hour calculated for processing the i-th workpiece, is the average man-hour carbon efficiency of the process, i.e. the man-hour carbon efficiency quota;

[0097] In order to quantitatively evaluate the carbon emissions generated in the complete manufacturing process of a certain process from a volume dimension, a material removal carbon efficiency quota is proposed. The material removal carbon efficiency quota is the average value of the material removal carbon efficiency obtained by processing n identical workpieces in this process. The calculation formula is:

[0098]

[0099]

[0100] Where: V strat is the volume of the workpiece before processing, V end STC is the volume of the workpiece after processing. iThe material removal carbon efficiency calculated for machining the i-th workpiece, It is the average material carbon removal efficiency of the process, that is, the material carbon removal efficiency quota.

[0101] Further, in this embodiment, the manufacturing process of turning a shaft workpiece (45# steel) is taken as an example, and the above method is used to carry out the carbon efficiency evaluation of the manufacturing process, wherein the processing equipment is a CA6140 lathe, and the tool is a carbide tool. The basic parameters of the lathe are shown in Table 1. The processing dimensions of the shaft parts are shown in Table 1. Figure 5 , the specific processing parameters are shown in Table 2:

[0102] Table 1 Basic parameters of CA6140 lathe

[0103]

[0104] Table 2 Workpiece dimensions and processing parameters of shaft parts

[0105]

[0106] First, according to the processing characteristics of the turning process, the system boundary of the turning process is defined, and the carbon emission source inventory analysis is carried out, such as Figure 6 As shown. The energy input in the turning process is mainly electricity; the material input is mainly raw material 45 steel, carbide tools and cutting fluid; the carbon emissions in the manufacturing process mainly include the treatment of the generated chips and waste fluid. The carbon emission coefficients of each substance are as follows: The density of 45 steel is 7.85g / cm 3 , its carbon emission coefficient is 8.2kgCO2e / kg; the carbon emission coefficient of commonly used turning tools is 38kgCO2e / kg, the average weight of a single blade is 9.5g, and the tool life is assumed to be T tool The carbon emission coefficient of electric energy is 0.86kgCO2e / kWh; the carbon emission coefficient of cutting fluid production is 4.5kgCO2e / kg; Since the carbon emissions generated by waste recycling and treatment are related to the treatment process, equipment and transportation distance, the carbon emission coefficient of chip treatment is set at 2.0kgCO2e / kg; the carbon emission coefficient of waste liquid treatment is 3.5kgCO2e / kg.

[0107] During turning, the machine tool mainly includes workpiece clamping, tool setting, cutting, rapid feeding, tool changing and workpiece unloading. This embodiment is a single-process single-step turning process without tool changing, so the tool changing state can be ignored. According to the processing history statistical data, the workpiece clamping time T clamp Take 30s; tool setting time T setting Take 2.5min; workpiece unloading time T transfer Take 20s. The rapid feed time Trapid It mainly refers to the time required for the tool to enter and cut out the non-cutting idle travel. For this single-step turning process, it can be calculated by formula (15), and the required time is 3.15s.

[0108]

[0109] Where: l x is the distance from the tool starting point to the workpiece axis, where l x The value is D / 2, the radius of the workpiece surface to be machined; L is the turning length; v x v is the maximum moving speed of the X axis; z It is the maximum moving speed of Z axis.

[0110] According to the turning material removal rate formula, the material removal rate of turning this shaft workpiece is 13.7 cm 3 / min, required cutting time T turning The total time consumed is 6.6 minutes, so the total time consumed is about 10 minutes.

[0111]

[0112]

[0113] T total =T clamp +T setting +T rapid +T turning +T transfer

[0114] =30+150+3.15+6.6×60+20

[0115] =599.16s≈10min

[0116] Among them, when the machine tool is in the workpiece clamping / unloading state, it is in the standby state; when it is in the tool setting and rapid feeding state, it is in the no-load state. According to the machine tool operation power data collected by the intelligent acquisition module, when it is in the standby state, its power is about 1.5kW; when it is in the no-load state, its power is about 2.8kW; when it is in the cutting state, its power is about 9.5kW.

[0117] According to the machine tool manual and empirical data, the average cutting fluid volume of the lathe is 16 kg, and the average monthly cutting fluid replenishment is 2 kg. The lathe is operated 20 days per month and one shift per day, so the average cutting fluid consumption per minute is 2.08 × 10 -4 kg / min. The total time for turning the shaft workpiece is 10 min, so the consumption of cutting fluid is about 2.08×10-3 kg; in order to ensure the processing quality and take into account the deterioration and failure of the cutting fluid, the cutting fluid replacement cycle is set to 2 months, which means that the cutting waste fluid generated by turning the shaft workpiece is about 9.38×10 -3 kg. For turning tools, due to T turning / T tool =0.022, which is far from the tool scrapping standard. The carbon emissions generated by the waste tool treatment here can be ignored.

[0118] Material Carbon Emissions:

[0119]

[0120] Energy Carbon Emissions:

[0121] CE r =CE elec =CF elec ×(P sb ×t sb +P idle ×t idle +P cut ×t cut )

[0122] =0.86×(1.5×50÷3600+2.8×153.15÷3600+9.5×396÷3600)

[0123] =1.02kgCO2e

[0124] Process carbon emissions:

[0125]

[0126] Total Carbon Emissions:

[0127] CE total =CE m +CE r +CE p =86.68+1.02+1.45=89.15kgCO2e

[0128] Man-hour carbon efficiency:

[0129]

[0130] Material carbon removal efficiency:

[0131]

[0132] According to the above method, in order to evaluate the carbon efficiency of the complete manufacturing process of the turning process, the machine tool is used to cut several identical shaft workpieces, and then their working hour carbon efficiency and material removal carbon efficiency are calculated respectively. Finally, the average values ​​of the corresponding working hour carbon efficiency and material removal carbon efficiency are solved respectively as the working hour carbon efficiency quota and material removal carbon efficiency quota. The results obtained can provide a production management basis for subsequent turning manufacturing and lay a foundation for carbon emission reduction.

[0133] Embodiment 2:

[0134] See also Figure 1 This embodiment discloses a method for evaluating carbon efficiency of a manufacturing process, comprising the following steps:

[0135] 1) Based on the characteristics of the manufacturing system, define the manufacturing process system boundary and conduct a carbon emission source inventory analysis;

[0136] 2) Classify the carbon emission sources in the manufacturing process according to the characteristics of the carbon emission sources. At the same time, define the corresponding generalized characteristic function of the carbon source according to the materials, energy consumption and process information of the manufacturing process, and establish the material carbon emission, energy carbon emission, process carbon emission and total carbon emission models of the manufacturing process;

[0137] 3) Combining the manufacturing process parameters, from the two dimensions of processing time and material removal, define the manufacturing process time carbon efficiency and material removal carbon efficiency, and establish their calculation models respectively;

[0138] 4) Based on the actual situation of the manufacturing process, the carbon efficiency quota of working hours and the carbon efficiency quota of material removal are proposed.

[0139] Embodiment 3:

[0140] The main steps of this embodiment are the same as those of Embodiment 2. Furthermore, the manufacturing process parameters described in step 3) include cutting parameters, workpiece materials, tool parameters and process conditions.

[0141] Embodiment 4:

[0142] The main steps of this embodiment are the same as those of Embodiment 2. Further, in step 2), the material carbon emissions refer to the carbon emissions generated in the material production process. The materials include raw materials and auxiliary materials. The auxiliary materials include cutting fluids and lubricating fluids. The generalized carbon characteristic function of the material is:

[0143]

[0144] in: is the generalized characteristic function of carbon source of carbon emission of the i-th material, which represents the consumption of the i-th material in this process; is the carbon emission characteristic function of raw materials, ρ1 is the density of raw materials, and x1 is the volume of raw materials; is the tool carbon emission characteristic function, ρ2 is the tool material density, and x2 is the tool material consumption volume converted in this process; is the carbon emission characteristic function of the cutting fluid, x3 is the average amount of cutting fluid consumed in the process during the use period of the cutting fluid; is the carbon emission characteristic function of the lubricant, x4 is the average amount of lubricant consumed by the process during the lubricant life cycle;

[0145] Energy carbon emissions refer to the carbon emissions generated by various energy sources consumed in the production process. The generalized characteristic function of energy carbon is:

[0146]

[0147] in: is the generalized characteristic function of carbon source of the j-th energy source carbon emission, which represents the consumption of the j-th energy source in the process; is the carbon emission characteristic function of electric energy, P sb is the standby power of the equipment during the manufacturing process, P idle is the no-load power of the equipment, P cut is the cutting power of the equipment, t sb ,t idle and y1 are the equipment standby time, equipment idle time and cutting time respectively; is the carbon emission characteristic function of compressed air, y2 is the volume of compressed air consumption; is the tap water carbon emission characteristic function, y3 is the tap water consumption volume;

[0148] The process carbon emissions refer to the carbon emissions generated by fuel combustion, chemical interactions between auxiliary materials, and post-processing of chips, waste cutting oil, and waste tools during the production process. The generalized characteristic function of process carbon is:

[0149]

[0150] in: is the generalized characteristic function of the carbon source of the kth direct emission or waste carbon emission, which represents the amount of the kth direct emission or waste of the process; is the carbon emission characteristic function of the waste chips to be processed, z1 is the amount of waste chips to be processed; is the carbon emission characteristic function of the waste cutting fluid to be treated for this process, z2 is the amount of waste cutting fluid to be treated; The carbon emission characteristic function of the worn waste tools to be processed is converted for this process, and z3 is the amount of waste tools to be processed.

[0151] Embodiment 5:

[0152] The main steps of this embodiment are the same as those of Embodiment 4. Further, in step 2), the calculation formulas for material carbon emissions, energy carbon emissions, process carbon emissions and total carbon emissions during the manufacturing process are as follows:

[0153] Material Carbon Emissions:

[0154]

[0155] Among them: CE m Carbon emissions from materials during the manufacturing process, is the carbon emission coefficient corresponding to the i-th material;

[0156] Energy Carbon Emissions:

[0157]

[0158] Among them: CE r Energy carbon emissions during the manufacturing process, is the carbon emission coefficient of the j-th energy source;

[0159] Process carbon emissions:

[0160]

[0161] Among them: CE p Carbon emissions from the manufacturing process. is the carbon emission coefficient of the kth direct emission / waste;

[0162] Total Carbon Emissions:

[0163]

[0164] Embodiment 6:

[0165] The main steps of this embodiment are the same as those of embodiment 5. Further, in step 2) and step 3), the man-hour carbon efficiency represents the carbon emissions generated by the manufacturing process per unit time. During the manufacturing process, the equipment has different operating states, including standby, no-load and processing. The man-hour carbon efficiency reflects the changes in carbon emissions of the manufacturing process in the time dimension. The man-hour carbon efficiency calculation formula is as follows:

[0166]

[0167] Where: T is the time consumed by the process;

[0168] The material removal carbon efficiency represents the carbon emissions generated by removing a unit volume of material. During the cutting process, the material removal carbon efficiency reflects the changes in carbon emissions in the manufacturing process in the volume dimension. The material removal carbon efficiency calculation formula is as follows:

[0169]

[0170] Where: V is the volume of workpiece material removed in this process, MRR is the material removal rate, and the material removal rate represents the amount of material removed per unit time in the manufacturing process;

[0171] The material removal rate calculation formula is:

[0172]

[0173] Where: ΔV is the volume change of the material per unit time, F(v C ,f,a p ,...) is the material removal characteristic function, v c is the cutting speed, f is the feed rate, a p The amount of knife damage on the back.

[0174] Embodiment 7:

[0175] The main steps of this embodiment are the same as those of embodiment 6. Further, in step 2) and step 4), the man-hour carbon efficiency quota is the average man-hour carbon efficiency obtained by processing n identical workpieces in the process, and the calculation formula is as follows:

[0176]

[0177]

[0178] Where: T i is the time consumed in processing the i-th workpiece in this process, STC i The carbon efficiency of the man-hour calculated for processing the i-th workpiece, The carbon efficiency quota for the man-hours of the process;

[0179] The material removal carbon efficiency quota is the average value of the material removal carbon efficiency obtained by processing n identical workpieces in this process, and the calculation formula is as follows:

[0180]

[0181]

[0182] Where: V strat is the volume of the workpiece before processing, V end STC is the volume of the workpiece after processing. iThe material removal carbon efficiency calculated for machining the i-th workpiece, Provides a carbon removal efficiency quota for the material in the process.

Claims

1. A method for evaluating carbon efficiency of a manufacturing process, characterized in that: The following steps are involved: 1) Based on the characteristics of the manufacturing system, define the manufacturing process system boundary and conduct a carbon emission source inventory analysis; 2) Based on the characteristics of carbon emission sources, classify the carbon emission sources in the manufacturing process, and define the corresponding generalized characteristic functions of carbon sources based on the materials, energy consumption and process information of the manufacturing process, and establish the material carbon emission, energy carbon emission, process carbon emission and total carbon emission models of the manufacturing process; The calculation formulas for material carbon emissions, energy carbon emissions, process carbon emissions and total carbon emissions during the manufacturing process are as follows: Material Carbon Emissions: Among them: CE m Carbon emissions from materials during the manufacturing process, is the carbon emission coefficient corresponding to the i-th material; Energy Carbon Emissions: Among them: CE r Energy carbon emissions during the manufacturing process, is the carbon emission coefficient of the j-th energy source; Process carbon emissions: Among them: CE p Carbon emissions from the manufacturing process. is the carbon emission coefficient of the kth direct emission / waste; Total Carbon Emissions: 3) Combining the manufacturing process parameters, from the two dimensions of processing time and material removal, define the manufacturing process carbon efficiency and material removal carbon efficiency, and establish their calculation models respectively; The man-hour carbon efficiency represents the carbon emissions generated by the manufacturing process per unit time. During the manufacturing process, the equipment has different operating states, including standby, no-load and processing. The man-hour carbon efficiency reflects the changes in carbon emissions of the manufacturing process in the time dimension. The man-hour carbon efficiency calculation formula is as follows: Where: T is the time consumed by the process; The material removal carbon efficiency represents the carbon emissions generated by removing a unit volume of material. During the cutting process, the material removal carbon efficiency reflects the changes in carbon emissions in the manufacturing process in the volume dimension. The material removal carbon efficiency calculation formula is as follows: Where: V is the volume of workpiece material removed in this process, MRR is the material removal rate, and the material removal rate indicates the amount of material removed per unit time in the manufacturing process; The material removal rate calculation formula is: Where: ΔV is the volume change of the material per unit time, F(v C ,f,a p ,...) is the material removal characteristic function, v c is the cutting speed, f is the feed rate, a p To eat knife quantity for back; 4) Based on the actual situation of the manufacturing process, the carbon efficiency quota of working hours and the carbon efficiency quota of material removal are proposed.

2. A manufacturing process carbon efficiency assessment method according to claim 1, characterized in that: The manufacturing process parameters in step 3) include cutting parameters, workpiece materials, tool parameters and process conditions.

3. A manufacturing process carbon efficiency assessment method according to claim 1, characterized in that: In step 2), the material carbon emission refers to the carbon emission generated in the material production process. The material includes raw materials and auxiliary materials. The auxiliary materials include cutting fluid and lubricating fluid. The generalized characteristic function of material carbon is: in: is the generalized characteristic function of carbon source of carbon emission of the i-th material, which represents the consumption of the i-th material in this process; is the carbon emission characteristic function of raw materials, ρ1 is the density of raw materials, and x1 is the volume of raw materials; is the tool carbon emission characteristic function, ρ2 is the tool material density, and x2 is the tool material consumption volume converted in this process; is the carbon emission characteristic function of the cutting fluid, x3 is the average amount of cutting fluid consumed in the process during the use period of the cutting fluid; is the carbon emission characteristic function of the lubricant, x4 is the average amount of lubricant consumed by the process during the lubricant life cycle; Energy carbon emissions refer to the carbon emissions generated by various energy sources consumed in the production process. The generalized characteristic function of energy carbon is: in: is the generalized characteristic function of carbon source of the j-th energy source carbon emission, which represents the consumption of the j-th energy source in the process; is the carbon emission characteristic function of electric energy, P sb is the standby power of the equipment during the manufacturing process, P idle is the no-load power of the equipment, P cut is the cutting power of the equipment, t sb ,t idle and y1 are the equipment standby time, equipment idle time and cutting time respectively; is the carbon emission characteristic function of compressed air, y2 is the volume of compressed air consumption; is the tap water carbon emission characteristic function, y3 is the tap water consumption volume; The process carbon emissions refer to the carbon emissions generated by fuel combustion, chemical interactions between auxiliary materials, and post-processing of chips, waste cutting oil, and waste tools during the production process. The generalized characteristic function of process carbon is: in: is the generalized characteristic function of the carbon source of the kth direct emission or waste carbon emission, which represents the amount of the kth direct emission or waste of the process; is the carbon emission characteristic function of the waste chips to be processed, z1 is the amount of waste chips to be processed; is the carbon emission characteristic function of the waste cutting fluid to be treated for this process, z2 is the amount of waste cutting fluid to be treated; The carbon emission characteristic function of the worn waste tools to be processed is converted for this process, and z3 is the amount of waste tools to be processed.

4. A manufacturing process carbon efficiency assessment method according to claim 3, characterized in that: In step 4), the man-hour carbon efficiency quota is the average man-hour carbon efficiency obtained by processing n identical workpieces in the process, and the calculation formula is as follows: Where: T i is the time consumed in processing the i-th workpiece in this process, STC i The carbon efficiency of the man-hour calculated for processing the i-th workpiece, The carbon efficiency quota for the man-hours of the process; The material removal carbon efficiency quota is the average value of the material removal carbon efficiency obtained by processing n identical workpieces in this process, and the calculation formula is as follows: Where: V strat is the volume of the workpiece before processing, V end STC is the volume of the workpiece after processing. i The material removal carbon efficiency calculated for machining the i-th workpiece, Provides a carbon removal efficiency quota for the material in the process.

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