Close Go back Collapse all sections
Process Data set: Machining of steel alloy DIN 20MnCr5, hobbing process, at plant, for industrial use, BR 2021 (en) pt

Key Data Set Information
Location BR
Geographical representativeness description All the input/output data were collected in the Brazilian South East Region, where more than 70% of automotive gears are produced in the country.
Reference year 2019
Name
Machining of steel alloy DIN 20MnCr5, hobbing process, at plant, for industrial use, BR 2021
General comment on data set This dataset represents a gear hobbing unit process for helical gears for automotive applications. The machined parts are made of steel alloy DIN 20MnCr5. It includes the inputs: semi-finished turned gear, coolant oil, compressed air, and electric energy; and the outputs: helical gear (main product), and metal chips impregnated with coolant oil. Emissions to air and heat generation were not included within the system boundary. Production of 36.000 gears per year based on a working scheme of 250 days with one shift of 8 hours and the process start-up/shutdown takes place just before/after the shift starts.
Copyright No
Quantitative reference
Reference flow(s)
Time representativeness
Data set valid until 2020
Time representativeness description The data was collected within the period 12/2019 - 10/2020
Technological representativeness
Technology description including background system Helical gears for the automotive industry are produced from steel alloy forged blanks, that are subsequentely turned to convert them into semi-finished gears. The gear hobbing process removes material from the semi-finished gear until all the gear teeth are formed. Afterwards the gears pass through heat treatment and teeth grinding processes to finish the manufacturing phase. The residues from the hobbing process are the nearly dry metal chips, which contain only traces of cutting integral oil used during hobbing.
Mathematical model
Variable / parameter Formula Mean value Minimum value Maximum value Uncertainty distribution type Relative StdDev in % General comment
Elect_Consum_ReadforProcessing 8.0E-5 % Corresponds to energy consumption during the Read for Processing process in in 1s
Elect_Consum_Processing 0.003925 % Corresponds to energy consumption during the machine processing process in in 1s
Time_Processing 1.0 % Corresponds to the total time to the machine stay in processing in seconds (s)
Time_WarmUp 1.0 % Corresponds to the total time to the machine stay in warmup in seconds (s)
Gear_Semifinished_total gear_SemiFinished *Time_Processing 0.075 % kg of gear steel come per cycle
Consum_Total_Electricity (elect_Consum_ExtStandby *Time_ExtStandby +Elect_Consum_Processing *Time_Processing +Elect_Consum_ReadforProcessing *Time_ReadforProcessing +Elect_Consum_Standby *Time_Standby +Elect_Consum_WarmUp *Time_WarmUp ) 0.00513 % electricity per cycle (kwh/s)
Gear_machined_total gear_machined *Time_Processing 0.06985 % kg of steel sustained per cycle
Integral_fluid_consum_total integral_fluid_consum *Time_Processing 3.59E-5 % l of integral fluid used per cycle
Elect_Consum_Standby 1.5E-4 % Corresponds to energy consumption during the process of standby the machine in in 1s
Time_ReadforProcessing 1.0 % Corresponds to the total time to the machine stay in read for processing in seconds (s)
Steel_chips_gear (gear_SemiFinished -Gear_machined )*Time_Processing 0.005150000000000002 % kg of steel removed per cycle
Integral_fluid_consum 3.59E-5 % Corresponds to the fluid consumption per second [liters for second]
Time_ExtStandby 1.0 % Corresponds to the total time to the machine stay in Extstandby in seconds (s)
Elect_Consum_ExtStandby 1.65E-4 % Corresponds to energy consumption during the process of Ext. standby the machine in 1s
Gear_SemiFinished 0.075 % Corresponds to the entrance of semi-finished geras for the machining process per second [Kg/s]
Elect_Consum_WarmUp 8.1E-4 % Corresponds to energy consumption during the WarmUp process in in 1s
Contamined_oil 1.4E-5 % Corresponds to the total contamined oil for second (kg for s)
Contamined_oil_total contamined_oil *Time_Processing 1.4E-5 % kg of contamined oil per cycle
Gear_machined 0.06985 % Represents the amount mass of the final product (machined parts per second) [Kg/s]
Time_Standby 1.0 % Corresponds to the total time to the machine stay in standby in seconds (s)
gd_price_waste 0.5 % This parameter was added by GreenDelta during the implementation of the ecoinvent database in openLCA. It is used by those exchanges which did not have a price specified by ecoinvent for being wastes (i.e. negative reference product), and that were considered that they should have a cost/revenue specified. The prices used for them, equal to the prices of the same product in other processes of the database, are modified by this parameter with value 0.5 (i.e. half the price of the normal product), considering that the reference product of a waste treatment process might have a lower price in reality than the same flow produced by a production process. However, you can modify this value to 0 if you prefer to consider no price for them like ecoinvent, or also 1 if you do not want to distinguish wastes from other products.
gd_price_product 1.0 % This parameter was added by GreenDelta during the implementation of the ecoinvent database in openLCA. It is used by those exchanges which did not have a price specified by ecoinvent and that were considered to be products or co-products of waste treatments (i.e. positive reference product), and that they should have a cost/revenue specified. The prices used for them, equal to the prices of the same product in other processes of the database, are modified by this parameter with value 1. However, you can modify this value to 0 if you prefer to consider no price for them like ecoinvent.
ei_price_product 1.0 % This parameter was added by GreenDelta during the implementation of the ecoinvent database in openLCA. It is used by those exchanges which did not have a price specified by ecoinvent in this specific system model, but yes in at least one of the other two system models. The prices used for them, equal to the prices of the same product and provider in the other system model, are modified by this parameter with value 1. However, you can modify this value to 0 if you prefer to consider no price for them in this system model like ecoinvent.
temp_olca_param23 gear_machined_total 0.06985 %
temp_olca_param24 gear_Semifinished_total 0.075 %
temp_olca_param25 contamined_oil_total 1.4E-5 %
temp_olca_param26 steel_chips_gear 0.005150000000000002 %
temp_olca_param27 consum_Total_Electricity 0.00513 %
temp_olca_param28 integral_fluid_consum_total 3.59E-5 %
LCI method and allocation
Type of data set Unit process, black box
LCI Method Principle Other
Deviation from LCI method principle / explanations Attributional method
Modelling constants No allocation rules were used for this dataset, as well as any of the transportation activities for the inputs. This is a G2G product system type.
Data sources, treatment and representativeness
Data cut-off and completeness principles Input flows with less than 1% mass representativeness were disregarded from the system boundaries. Emissions from treated air and heat represent low relevance due to their volume per functional unit (1 second of processing).
Deviation from data cut-off and completeness principles / explanations None.
Data selection and combination principles Primary data were collected for the machining production system. See 'Geography' and 'Technology' scopes for more details.
Deviation from data selection and combination principles / explanations None.
Data treatment and extrapolations principles All the input/output data were converted to the functional unit of 1s of manufacturing operation by using the UPLCI methodology developed by Kellens et al. (2012a,b). All the collected input/output flows followed the "in-depth assessment" approach proposed by the UPLCI methodology.
Data source(s) used for this data set
Sampling procedure Resources and emissions at the production site, assumed the use of one machine-tool to describe a gear hobbing machine of steel alloy parts, equipped with MQL.
Data collection period See 'Time' scope for more details.
Completeness
Completeness of product model No statement
Commissioner and goal
Project SOARES, Luiz Arthur Paluch. ACV Comparativa entre processo de fresamento de engrenagens automotivas. 2020. 107 f. Dissertação (Mestrado) - Curso de Engenharia de Produção, Universidade Federal de São Carlos, Sorocaba, 2021.
Intended applications This process LCI can be used for any types of LCA studies.
Data generator
Data set generator / modeller
Data entry by
Time stamp (last saved) 2021-05-20T15:00:23.490-03:00
Data set format(s)
Data entry by
Publication and ownership
UUID d20cb0b7-4235-415e-b514-745dbe76883b
Date of last revision 2021-05-20T14:59:01.259-03:00
Data set version 00.00.119
Unchanged re-publication of
Copyright No
Access and use restrictions The data set can be used free of charge by anybody to perform LCA studies, to distribute it to third parties, to convert it to other LCA formats, to develop own data sets, etc.

Inputs

Type of flow Classification Flow Variable Mean amount Resulting amount Minimum amount Maximum amount
Product flow
temp_olca_param24 1.0 kg0.075 kg
General comment The raw material (workpiece) is a turned semi-finished gear to be machined in the hobbing process.
Product flow
Energy carriers and technologies / Electricity temp_olca_param27 1.0 MJ0.018468000000000002 MJ
General comment Total electric energy consumed by the machine tool over the five production modes.
Product flow
temp_olca_param28 1.0 m33.59E-8 m3
General comment The composition of this cutting fluid R134A is HFC(hydrofluorocarbons).

Outputs

Type of flow Classification Flow Variable Mean amount Resulting amount Minimum amount Maximum amount
Product flow
temp_olca_param23 1.0 kg0.06985 kg
General comment The total amount of metal gear (output) after the machining process.
Waste flow
temp_olca_param25 1.0 kg1.4E-5 kg
General comment Represents the contamined oil of the cutting fluid (R134A) after the machining process.
Waste flow
temp_olca_param26 1.0 kg0.005150000000000002 kg
General comment Represents the amount of metal chips removed from the machining process.