Tube or pipe fittings, of steel other than cast-steel

1. Scope and Applicability

This PCR applies to finished wrought or otherwise non-cast steel fittings used to join, branch, reduce, redirect, close, or terminate tube and pipe runs. Covered products include butt-welding elbows, bends, tees, reducers, caps and ends; threaded or socket-welding fittings; and steel flanges when they meet the declared product-category boundary. Carbon, low-alloy, alloy, and stainless steel grades are included when the fitting is not produced as a cast-steel fitting.

Cast-iron fittings, cast-steel fittings, unconverted tubes or pipes, valves, installation services, use, maintenance, and end-of-life are excluded. The foreground gate begins with purchased steel tube, pipe, billet, and other separately identified production inputs received at the fitting plant and ends with unpackaged conforming fittings at the factory gate. Packaging may be added only by a separately declared downstream packaging process and is not part of this reference product.

2. Product Category Identity

Field	Value
canonical_pcr_id	pcr.metal-products-machinery-and-equipment.basic-metals.tube-or-pipe-fittings-of-steel-other-than-cast-steel
classification_refs	CPC 3.0: 41293, exact mapping context
covered_products	Non-cast steel elbows, bends, tees, reducers, caps, ends, threaded fittings, socket-welding fittings, butt-welding fittings, and flanges for tube or pipe systems
excluded_products	Cast-iron or cast-steel fittings; tubes and pipes sold without conversion to fittings; valves; installation services; packaging unless separately declared
representative_product	A finished steel butt-welding elbow, tee, reducer, cap, end, or comparable fitting conforming to the declared specification
production_route	Cutting and preparation followed by pipe forming, hot forming, forging, welding, machining, heat treatment, cleaning, pickling, galvanizing, and finishing as applicable to the declared fitting
market_state	Finished, inspected, unpackaged fitting at the factory gate; steel grade, dimensions, connection type, heat-treatment state, and coating state declared

3. Reference Flow

Field	Value
What	Provide a finished non-cast steel fitting that joins, branches, reduces, redirects, closes, or terminates a declared tube or pipe run
How much	1 kg of conforming finished fitting at the factory gate
How well	Meets the declared fitting geometry, connection type, steel grade, dimensions, tolerances, heat-treatment state, surface condition, and applicable quality specification
How long or cycle	One factory-gate production reporting period; service life and use are not modelled
reference_flow_link	1 kg of conforming finished fitting output equals 1 kg of the reference product flow

Field	Value
Reference amount	1 kg
Reference product flow	Tube or pipe fittings, of steel other than cast-steel 927f577f-735f-45ce-915c-5cac28802501
Reference flow property	Mass 93a60a56-a3c8-11da-a746-0800200b9a66
Reference unit group	Units of mass 93a60a57-a4c8-11da-a746-0800200c9a66
Reference unit	kg
Required qualifiers	fitting type and connection type; nominal size and wall thickness or schedule; steel grade and material specification; pipe-forming, forging, or welded-fabrication route; heat-treatment state; surface and coating state; conformance standard; plant geography; reporting period; upstream steel dataset identity; scrap and spent-acid destination

When constructing a foreground data package, the items listed in Required qualifiers must be declared in dataset metadata, process notes, reference flow comment, product description, or an equivalent data package field. Missing required qualifiers make the reference flow definition incomplete for that data package.

4. Measurement and Unit Rules

rule_id	Applies to	Required property	Required unit	Rule
reference_product_mass	reference product and steel-bearing material balance	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg	Weigh conforming, unpackaged finished fittings after final inspection; exclude rejected fittings, removable transport fixtures, and packaging.
gas_reference_conditions	natural gas and industrial oxygen	Volume 93a60a56-a3c8-22da-a746-0800200c9a66	m3	Record the meter reference temperature and pressure and convert all reported gas volumes to one declared reference condition before aggregation.
electricity_energy_basis	purchased electricity	Energy	kWh	Preserve metered electricity in kWh; if source records use MJ, apply 1 kWh = 3.6 MJ and retain the original record and conversion.
solution_mass_basis	sodium hydroxide and hydrochloric acid solutions	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg	Record delivered solution mass and concentration separately; do not mix solution mass with dry active-substance mass. The selected hydrochloric-acid row represents 30% delivered solution.
mass_normalization	all mass-based inventory rows	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg/kg reference product	Normalize reporting-period totals by conforming finished fitting mass from the same plant, route, and reporting period.

5. System Boundary

Boundary Abstraction

Field	Value
declared_starting_condition	Purchased steel tube, pipe, or billet and separately identified auxiliary inputs received at the fitting plant
starting_condition_role	Foreground conversion gate; purchased-input production remains represented by linked upstream datasets
product_classification_scope	Finished non-cast steel tube or pipe fittings; cast-iron and cast-steel fittings are outside scope
recursive_input_rule	If a purchased input is itself a fitting in this PCR category, record it as a separate product input with its upstream dataset and do not recursively expand its fitting manufacture inside the same foreground process
upstream_dataset_requirement	Link each purchased steel form, electricity supply, fuel, gas, water, chemical, and zinc input to a geographically and technologically representative upstream dataset; disclose substitutions and missing datasets
disclosure	Declare steel form and grade, fitting type, route, heat treatment, joining operations, pickling and galvanizing applicability, reference conditions for gas, factory geography, reporting period, and waste destinations

rule_id	Applies to	Rule	source_ids
boundary_conversion_operations	on-site fitting manufacture	Include on-site cutting, heating and metal treatment, pipe forming or forging, welding, machining, cooling and finishing, heat treatment, cleaning, inspection, and testing when those operations occur.	eu-jrc-sf-bref-2024
boundary_surface_treatment	on-site pickling or galvanizing	Include on-site degreasing, pickling, fluxing, hot-dip galvanizing, rinsing, and finishing only when performed for the declared product route; otherwise mark every related atomic flow not applicable.	eu-jrc-fmp-bref-2022
boundary_upstream_inputs	purchased inputs	Keep production of purchased steel and auxiliary inputs outside the foreground conversion gate but connect each input to an upstream dataset.	eu-jrc-fmp-bref-2022
boundary_category_exclusions	product identity	Exclude cast-iron and cast-steel fittings and unconverted tube or pipe products from the reference product.	unsd-cpc-3-0-structure-2025
boundary_downstream	downstream life cycle	Exclude distribution packaging, installation, use, maintenance, and end-of-life unless a study explicitly adds separate downstream processes.

6. Process Inventory Structure

Process Map

process_id	process_name	inclusion	inclusion_condition	role	quantitative_reference
steel_fitting_manufacture	Integrated manufacture of non-cast steel tube or pipe fittings	required	Required for every covered product; individual input and output cards state route conditions	Foreground conversion from purchased steel form to conforming finished fitting	1 kg conforming finished fitting at factory gate

Process: Integrated manufacture of non-cast steel tube or pipe fittings (steel_fitting_manufacture)

Inputs

Product flows

Welded circular steel pipe feedstock (input_welded_steel_pipe)

Record this input only when a fitting is formed or fabricated from purchased welded circular pipe stock. Match grade, diameter, wall thickness, coating state, and supplier dataset to the declared fitting.

• Selected flow: Steel Pipe 370d14a6-55f3-4fdd-90b2-84751125ff00
• Flow property / unit: Mass / kg
• Amount rule: measured mass of welded circular steel pipe entering fitting manufacture
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_steel_feedstock
• Sources:

Seamless circular steel tube feedstock (input_seamless_steel_tube)

Record this concrete flow only for a route that forms the fitting from purchased circular seamless steel tube. Its exact Tiangong UUID remains unresolved; do not substitute oil-and-gas line pipe, casing, non-circular tube, or welded pipe.

• Selected flow: Circular seamless steel tube feedstock
• Flow property / unit: Mass / kg
• Amount rule: measured mass of circular seamless steel tube entering fitting manufacture
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_steel_feedstock
• Sources:

Non-alloy steel billet feedstock (input_nonalloy_steel_billet)

Record this input only for a forged or hot-formed non-alloy steel fitting route that begins with purchased billet.

• Selected flow: Billet 7de70586-42d8-40bb-a687-e0e0c05722e4
• Flow property / unit: Mass / kg
• Amount rule: measured mass of non-alloy steel billet entering the forging or hot-forming route
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_steel_feedstock
• Sources:

Alloy steel billet feedstock (input_alloy_steel_billet)

Record this concrete flow only for a forged or hot-formed alloy-steel fitting route that begins with purchased billet. Its exact Tiangong UUID remains unresolved; an alloy-steel ingot is not a billet proxy.

• Selected flow: Alloy steel billet
• Flow property / unit: Mass / kg
• Amount rule: measured mass of alloy steel billet entering the forging or hot-forming route
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_steel_feedstock
• Sources:

Purchased medium-voltage electricity (input_electricity)

Record metered electricity consumed by cutting, forming, welding, machining, heat treatment, pumps, ventilation, surface treatment, and finishing. The supply voltage, grid geography, supplier mix, and delivery boundary must be declared.

• Selected flow: Medium-voltage electricity
• Flow property / unit: Energy / kWh
• Amount rule: metered purchased medium-voltage electricity consumed by the process
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_energy_metering
• Sources:

Gaseous natural gas (input_natural_gas)

Record this flow only when natural gas is combusted on site for heating, hot forming, heat treatment, or drying. State the meter reference conditions and exclude upstream supply-chain emissions from the direct-emission row.

• Selected flow: natural gas in the gaseous state 4f19ca0e-7b3b-11dd-ad8b-0800200c9a66
• Flow property / unit: Volume / m3
• Amount rule: metered gaseous natural gas delivered to the fitting-manufacture process
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_energy_metering
• Sources:

Industrial oxygen (input_industrial_oxygen)

Record this flow only for oxy-fuel cutting, heating, or another declared operation that consumes supplied industrial oxygen. Declare purity, pressure, volume reference conditions, and whether supply is delivered or generated on site.

• Selected flow: Industrial oxygen bd4b0f96-2090-4806-a648-335ab20ff401
• Flow property / unit: Volume / m3
• Amount rule: metered or supplier-recorded industrial oxygen consumed by the process
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_process_gases
• Sources:

Process water (input_process_water)

Record process water entering cooling, cleaning, rinsing, pickling-bath make-up, or galvanizing-related operations. Cooling water recirculated entirely within the plant is not counted again; only net make-up crossing the boundary is recorded.

• Selected flow: Process Water 94a04f7e-2d5c-41f0-b182-d54a3b373a02
• Flow property / unit: Mass / kg
• Amount rule: measured net process-water input crossing the foreground boundary
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_process_water
• Sources:

Sodium hydroxide solution (input_sodium_hydroxide)

Record this flow only when sodium hydroxide solution is used for alkaline degreasing or cleaning. Report delivered solution mass and concentration separately.

• Selected flow: Sodium hydroxide e0abcced-0611-4c24-9290-5a2c5a0c4169
• Flow property / unit: Mass / kg
• Amount rule: measured delivered mass of sodium hydroxide solution consumed by on-site cleaning
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_surface_chemicals
• Sources:

Hydrochloric acid solution at 30% (input_hydrochloric_acid_30pct)

Record this flow only when purchased 30% hydrochloric acid solution is used for on-site pickling. Other delivered concentrations require a distinct concentration-specific flow identity or a reviewed mass-of-solution conversion.

• Selected flow: Hydrochloric acid (30%) 56414d25-a353-4d67-b362-87212ce6011d
• Flow property / unit: Mass / kg
• Amount rule: measured delivered mass of 30% hydrochloric acid solution consumed by pickling
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_surface_chemicals
• Sources:

Special high grade zinc metal (input_zinc_metal)

Record this flow only when special-high-grade zinc metal is added to an on-site hot-dip galvanizing bath. Record total supplied metal mass, not zinc-content mass from an ore or concentrate flow.

• Selected flow: Special High Grade zinc metal 2d8ff1bd-e128-4c74-a99d-b8734c99bbd2
• Flow property / unit: Mass / kg
• Amount rule: measured mass of special-high-grade zinc metal charged to the galvanizing bath and attributable to the product
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_surface_chemicals
• Sources:

Waste flows

Elementary flows

Outputs

Product flows

Conforming finished steel fitting (output_reference_product)

Record only finished fittings that pass the declared dimensional, material, heat-treatment, surface, and quality checks. Rejected fittings are not part of this output.

• Selected flow: Tube or pipe fittings, of steel other than cast-steel 927f577f-735f-45ce-915c-5cac28802501
• Flow property / unit: Mass / kg
• Amount rule: measured mass of conforming unpackaged finished fittings at the factory gate
• Value mode: Foreground record (foreground_record)
• Specificity: Product-specific (product_specific)
• Normalization basis: 1 kg reference product output
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_product_output
• Sources: bsi-bs-en-10253-2-2021-a1-2025

Waste flows

Post-industrial steel scrap (output_postindustrial_steel_scrap)

Record separately collected steel offcuts, machining chips, forging flash, and rejected steel generated by the plant. Keep alloy grades and contaminated scrap separate in the underlying records and declare the receiving treatment route.

• Selected flow: Post-industrial steel scrap c143745d-be4f-4d8f-b403-2dcbfe685349
• Flow property / unit: Mass / kg
• Amount rule: measured mass of post-industrial steel scrap leaving the foreground process
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_waste_dispatch
• Sources:

Spent hydrochloric-acid pickling liquor (output_spent_pickling_acid)

Record this concrete waste only when a hydrochloric-acid pickling bath is removed from service and crosses the plant boundary. Record its mass, acid concentration, dissolved-metal content, and treatment destination; the exact Tiangong waste UUID remains unresolved.

• Selected flow: Spent hydrochloric-acid steel pickling liquor
• Flow property / unit: Mass / kg
• Amount rule: measured mass of spent hydrochloric-acid pickling liquor dispatched off site
• Value mode: Foreground record (foreground_record)
• Specificity: Technology-specific (technology_specific)
• Normalization basis: per 1 kg conforming finished fitting produced over the bath service period
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_waste_dispatch
• Sources:

Elementary flows

Direct fossil carbon dioxide (output_fossil_carbon_dioxide)

Record only direct fossil carbon dioxide emitted by on-site combustion assigned to fitting manufacture. Do not include upstream electricity, natural-gas supply, or purchased-material emissions in this elementary-flow row.

• Selected flow: carbon dioxide (fossil) 08a91e70-3ddc-11dd-923d-0050c2490048
• Flow property / unit: Mass / kg
• Amount rule: measured or independently verified site record of direct fossil carbon dioxide assigned to the process
• Value mode: Foreground record (foreground_record)
• Specificity: Site-specific (site_specific)
• Normalization basis: per 1 kg conforming finished fitting
• Basis kind: Reference flow (reference_flow)
• Evidence kind: Collected record (collected_record)
• Collection protocol: cp_direct_emissions
• Sources:

7. Allocation and Co-product Handling

rule_id	Applies to	Rule	source_ids
allocation_subdivide_first	separately metered routes, lines, or batches	Subdivide fitting routes, lines, and batches and assign their directly measured steel, energy, chemical, water, waste, and emission records before applying allocation.
allocation_shared_operations	shared operations producing several fitting products	If subdivision is not practicable, use a documented physical driver that reflects consumption, such as machine time, furnace load, metered energy, or processed mass; use mass allocation only when no more representative measured driver exists.
allocation_scrap	post-industrial steel scrap	Treat steel scrap leaving the process as a waste flow at the foreground boundary; do not apply an avoided-production credit inside this process. A downstream recycling model may represent subsequent treatment separately.

8. Foreground Data Collection, Calculation, and Quality Rules

Data Collection Protocols

protocol_id	process_id	flow_role	record_type	raw_fields	collection_method	unit	frequency	temporal_coverage	site_scope	aggregation_rule	quality_evidence
cp_steel_feedstock	steel_fitting_manufacture	each declared steel feedstock card	receiving scale, purchase, and production issue records	material identity; heat or lot; steel grade; product form; dimensions; received mass; issued mass; supplier dataset	reconcile calibrated scale tickets and material issues to production lots	kg	per receipt and production lot	complete reporting period	all lines producing the declared fitting	sum only the applicable steel-form row and normalize by conforming output mass	scale calibration; heat certificates; purchase documents; lot reconciliation
cp_energy_metering	steel_fitting_manufacture	purchased electricity and natural gas	utility meters and invoices	meter id; opening and closing readings; unit; reference conditions for gas; allocation driver; downtime	read dedicated meters or allocate a reconciled plant meter with a documented physical driver	kWh; m3	continuous or at least monthly	complete reporting period	all included equipment and shared utilities	subtract verified non-production use and normalize to conforming output mass	meter calibration; invoices; reconciliation; allocation worksheet
cp_process_gases	steel_fitting_manufacture	industrial oxygen	flow meter, cylinder, or tank delivery records	gas identity; purity; pressure; reference temperature; reference pressure; delivered and closing inventory	reconcile meters or deliveries and stock change to consumed gas	m3	per delivery and reporting period	complete reporting period	oxy-fuel operations for the declared route	consumed volume equals deliveries plus opening stock minus closing stock, converted to declared conditions	supplier certificate; meter calibration; stock reconciliation
cp_process_water	steel_fitting_manufacture	process water	water meter and make-up records	meter readings; source; treatment; recirculation; make-up volume or mass; discharge linkage	meter net make-up crossing the process boundary	kg	continuous or at least monthly	complete reporting period	cooling, cleaning, rinsing, pickling, and galvanizing systems in scope	exclude internal recirculation and normalize net input to conforming output mass	meter calibration; water balance; invoice or abstraction record
cp_surface_chemicals	steel_fitting_manufacture	sodium hydroxide, 30% hydrochloric acid, and SHG zinc	purchase, batch-charge, bath-analysis, and stock records	chemical identity; concentration or grade; delivered mass; charged mass; opening and closing stock; bath id; applicable lots	reconcile deliveries, charges, and stock change for each separate chemical	kg	per charge and reporting period	complete bath service periods overlapping the reporting period	all cleaning, pickling, and galvanizing baths used for the declared product	attribute each chemical separately by measured product throughput through the bath	supplier certificate; concentration analysis; calibrated scale; stock reconciliation
cp_product_output	steel_fitting_manufacture	conforming reference product	final scale, inspection, and release records	product id; fitting type; connection; dimensions; grade; heat treatment; coating; mass; inspection result; release date	weigh and release only conforming unpackaged fittings	kg	per lot	complete reporting period	all declared fitting production lines	sum conforming mass by homogeneous declared product and route	scale calibration; inspection report; material certificate; release record
cp_waste_dispatch	steel_fitting_manufacture	post-industrial steel scrap and spent pickling acid	waste scale tickets, manifests, and bath replacement records	waste identity; alloy or contamination; mass; bath id; acid concentration; dissolved metals; date; destination; treatment	reconcile internal collection with off-site dispatch documents for each waste	kg	per dispatch and bath replacement	complete reporting period and complete bath service period	all included operations	sum each waste separately and attribute shared bath waste by product throughput through that bath	calibrated scale; waste manifest; bath analysis; licensed receiver record
cp_direct_emissions	steel_fitting_manufacture	direct fossil carbon dioxide	CEMS, stack-test-supported records, or verified facility emissions records	source id; fuel linkage; measured mass or verified reported mass; operating period; allocation driver	use direct measurement where available and reconcile the covered combustion sources to the natural-gas record	kg	continuous or reporting-period record	complete reporting period	on-site fossil combustion assigned to fitting manufacture	subtract excluded sources and normalize the assigned mass to conforming output	instrument QA records; emissions report; fuel-to-emission reconciliation

Calculation Rules

rule_id	Applies to	Formula or rule	Inputs	Output	source_ids
calc_reference_normalization	every inventory row	normalized amount = reporting-period row total divided by reporting-period conforming unpackaged fitting mass	row total; conforming product mass	amount per 1 kg reference product
calc_gas_condition_conversion	natural gas and industrial oxygen	convert reported gas volume to the single declared reference temperature and pressure using the documented meter or supplier correction method before normalization	reported volume; temperature; pressure; compressibility method if used	m3 at declared reference conditions
calc_steel_yield_check	steel-bearing inputs and outputs	compare total applicable steel feedstock mass with conforming fitting mass plus steel scrap and other separately documented steel-bearing stock changes or residues	steel feedstock; conforming fitting; steel scrap; stock changes; separately documented residues	disclosed steel mass-balance difference

Data Quality Requirements

requirement_id	Applies to	Requirement	Evidence
dq_product_identity	reference product	Fitting type, connection, dimensions, steel grade, manufacturing route, heat-treatment state, coating state, and conformance specification are complete and internally consistent.	release record; drawing; material certificate; inspection report
dq_temporal_match	all inventory rows	Input, output, waste, and direct-emission records cover the same declared reporting period; bath-service allocations state any period mismatch.	reporting-period reconciliation and bath-service worksheet
dq_metering	energy, gases, water, and mass records	Meters and scales have current calibration or a documented accuracy check; estimated substitutions are flagged and justified.	calibration certificates; invoice reconciliation; uncertainty note
dq_route_completeness	conditional operations	Every forming, forging, welding, heat-treatment, pickling, and galvanizing operation is declared present or absent, and all applicable atomic rows are completed.	route sheet; process flow diagram; production traveller
dq_upstream_links	purchased inputs	Each applicable purchased-input row links to a representative upstream dataset or reports the identity, geography, technology, and substitution gap.	dataset references and substitution log
dq_mass_balance	steel-bearing flows	Investigate and explain the steel mass-balance difference rather than forcing it to zero or hiding stock changes and residues.	signed reconciliation; inventory-change record; corrective-action note

9. Validation Rules

rule_id	Applies to	Rule	source_ids
validate_reference_identity	reference product	Confirm the reference product is the exact non-cast steel fitting flow and not a cast fitting or unconverted tube or pipe.	unsd-cpc-3-0-structure-2025
validate_reference_amount	reference flow	Confirm exactly 1 kg of conforming unpackaged output is the normalization denominator and all rows use the same product and reporting period.
validate_product_qualifiers	product release	Confirm the declared fitting types, steel grades, dimensions, tolerances, inspection and testing requirements, and quality requirements are supported by product records and the applicable specification.	bsi-bs-en-10253-2-2021-a1-2025
validate_route_rows	process inventory	Confirm every route operation is declared and each conditional atomic flow is completed only when that operation occurs.	eu-jrc-sf-bref-2024; eu-jrc-fmp-bref-2022
validate_solution_basis	surface-treatment chemicals	Confirm sodium hydroxide and hydrochloric acid are reported as delivered solution mass with concentration and that the selected hydrochloric-acid flow is used only for a verified 30% solution.
validate_waste_destination	steel scrap and spent pickling acid	Confirm each waste has a measured mass, declared composition or contamination state, and named receiving treatment; do not merge scrap and acid waste.
validate_direct_co2_boundary	direct fossil carbon dioxide	Confirm the row contains only on-site fossil combustion emissions and excludes upstream electricity, natural-gas supply, and purchased-material emissions.
validate_allocation	shared operations	Confirm subdivision was attempted first and any remaining physical allocation driver, basis, and affected rows are disclosed.

10. Published Dataset Profile

Field	Value
dataset_role	Factory-gate foreground production dataset for finished non-cast steel tube or pipe fittings
downstream_use	May be published as a secondary_dataset or background_dataset for declared fitting types and manufacturing routes
allowed_use	Product LCAs and lifecycle models that match the declared steel grade, fitting type, route, dimensions, coating, geography, reporting period, and factory-gate boundary
excluded_use	Cast-iron or cast-steel fittings; unconverted pipe; valves; installation, use, or end-of-life; products with undisclosed route or material state
required_metadata	PCR id and version; product flow UUID; fitting type; connection type; nominal size and wall thickness; steel grade and specification; route; heat treatment; coating; geography; reporting period; upstream datasets; allocation; data quality
required_quality_disclosure	Foreground coverage; measured and estimated shares; meter and scale quality; steel mass-balance difference; conditional-process applicability; unresolved UUID substitutions; upstream dataset representativeness; waste destinations
update_trigger	Change in steel grade or feedstock form, forming or forging technology, heat-treatment fuel, electricity supply, pickling chemistry, galvanizing route, product specification, allocation driver, plant geography, or a material shift in foreground intensity

11. Data Sources

Source id	Type	Reference	Used for
unsd-cpc-3-0-structure-2025	Official guidance (official_guidance)	United Nations Statistics Division, CPC Version 3.0 Structure, 30 June 2025, https://unstats.un.org/unsd/classifications/Econ/Download/In%20Text/CPC_Ver_3.0_Structure_30Jun2025.csv	Exact CPC 41293 product identity and exclusion of cast-steel fittings
bsi-bs-en-10253-2-2021-a1-2025	Standard (standard)	BSI, BS EN 10253-2:2021+A1:2025, Butt-welding pipe fittings — Non-alloy and ferritic alloy steels with specific inspection requirements, https://knowledge.bsigroup.com/products/butt-welding-pipe-fittings-non-alloy-and-ferritic-alloy-steels-with-specific-inspection-requirements-2	Representative butt-welding fitting types and required declaration of steel grade, dimensions, tolerances, inspection, testing, and applicable quality specification
eu-jrc-sf-bref-2024	Official guidance (official_guidance)	European Commission Joint Research Centre, Best Available Techniques Reference Document for the Smitheries and Foundries Industry, 2024, https://bureau-industrial-transformation.jrc.ec.europa.eu/reference/smitheries-and-foundries-industry	Forging-route process decomposition: heating, metal treatment, forging or hammering, machining, cooling or finishing, and heat treatment
eu-jrc-fmp-bref-2022	Official guidance (official_guidance)	European Commission Joint Research Centre, Ferrous Metals Processing Industry BREF, 2022, https://bureau-industrial-transformation.jrc.ec.europa.eu/reference/ferrous-metals-processing-industry	Downstream ferrous-metal boundary and conditional batch-galvanizing sequence of degreasing, pickling, fluxing, galvanizing, and finishing