Finished lug-brazed steel bicycle frame manufacturing

1. Scope and Applicability

Manufacture of a new standalone finished diamond frame for a nonmotorized bicycle, using identified cold-worked non-stainless chrome-moly steel tube members, supplied steel socket lugs/bottom-bracket shell/rear dropouts, qualified uncoated copper-zinc filler and formulated brazing flux. Scope starts at received manufactured tubes and components, includes local cut/trim/miter/fit/alignment and lug brazing, specified braze-ons, actual cleaning/surface preparation, spray-applied metal etch primer and solvent-borne alkyd colour stove-enamel with actual electric baking, conditional clear enamel, final interface/geometry/finish acceptance and independent frame-only dispatch. Actual matched grade/butt profile/socket/joining/finish qualification and released drawings govern; no universal material recipe or Mercian brand specification is mandated.

Exclude complete bicycles and riding/service outputs, frame-and-fork sets, forks/headsets/bottom-bracket cartridges/wheels/brakes/transmission, wheelchair components, motorized/e-bike/motorcycle frames, aluminium/titanium/carbon/stainless frames, suspension/step-through/folding/tandem structures, TIG-welded or lugless fillet-only frames, uncoated intermediate-only outputs, bought-complete-frame finishing-only routes, repair/restoration and upstream tube butting/steelmaking/lug casting. Heat-treated or joining-sensitive grades requiring different qualified filler/thermal practice are outside this cold-worked brass-lug subroute. Customer complete-bike assembly, use/maintenance and end of life excluded. Attributable actual factory inspection/type/sample testing included; foreground alone is not full cradle-to-gate or proof of riding performance/life.

Overlap decision: the current material scan has no independent bicycle-frame method; retained complete-cycle/parts/carriage leaves are scaffolds. A complete bicycle may contain the same frame production steps, but this output is independently accepted finished frame, excludes fork/wheel/brake/drive assembly and needs member butt/trim, socket joining, frame-datum/interface control and frame-only net mass. Reuse shared manufacturing evidence and generic normalization/allocation, not whole-cycle reference or riding-service tests. Scientific review and methodology approval remain pending.

2. Product Category Identity

Field	Value
canonical_pcr_id	pcr.metal-products-machinery-and-equipment.transport-equipment.bicycle-structural-parts
classification_refs	CPC:3.0:49942; narrower; category context, no accepted mapping
covered_products	Manufacture of a new standalone finished diamond frame for a nonmotorized bicycle, using identified cold-worked non-stainless chrome-moly steel tube members, supplied steel socket lugs/bottom-bracket shell/rear dropouts, qualified uncoated copper-zinc filler and formulated brazing flux. Scope starts at received manufactured tubes and components, includes local cut/trim/miter/fit/alignment and lug brazing, specified braze-ons, actual cleaning/surface preparation, spray-applied metal etch primer and solvent-borne alkyd colour stove-enamel with actual electric baking, conditional clear enamel, final interface/geometry/finish acceptance and independent frame-only dispatch. Actual matched grade/butt profile/socket/joining/finish qualification and released drawings govern; no universal material recipe or Mercian brand specification is mandated.
excluded_products	Exclude complete bicycles and riding/service outputs, frame-and-fork sets, forks/headsets/bottom-bracket cartridges/wheels/brakes/transmission, wheelchair components, motorized/e-bike/motorcycle frames, aluminium/titanium/carbon/stainless frames, suspension/step-through/folding/tandem structures, TIG-welded or lugless fillet-only frames, uncoated intermediate-only outputs, bought-complete-frame finishing-only routes, repair/restoration and upstream tube butting/steelmaking/lug casting. Heat-treated or joining-sensitive grades requiring different qualified filler/thermal practice are outside this cold-worked brass-lug subroute. Customer complete-bike assembly, use/maintenance and end of life excluded. Attributable actual factory inspection/type/sample testing included; foreground alone is not full cradle-to-gate or proof of riding performance/life.
representative_product	One finished standalone steel diamond bicycle frame in one declared geometry, specified tube/lug/dropout/bridge/braze-on configuration, accepted coated state. Mercian/Reynolds are process/material examples, no mandatory model or supplier.
production_route	Received tube inspection, butt-aware cutting and miter preparation; Lugged frame alignment, brazing and braze-on completion; Surface preparation, metal primer and electric-baked enamel; Frame-only geometry/interface acceptance, weighing and dispatch
market_state	New complete finished frame alone at frame maker dispatch; wheels/fork/headset/bottom-bracket cartridge and loose parts/packaging outside M. Permanently retained filler, fittings and dry finish included.

3. Reference Flow

Field	Value
What	Manufacture and acceptance of one declared finished frame-only structural part.
How much	1kg accepted net frame output from actual M kg per complete same-configuration finished frame. An accepted unit is one complete frame, not complete bicycle, frameset, rider load or tube kit.
How well	Current released geometry/grade/butt/lug/thermal/finish specification, frame alignment and shell/head/seat/dropout interfaces, actual contract-defined inspection and attributable sample/type testing. No universal rider load or fatigue cycle prescribed.
How long or cycle	One manufacturing acceptance and dispatch cycle, not a service life or distance output.
reference_flow_link	finished_machine

Field	Value
Reference amount	1
Reference product flow	Complete finished lug-brazed steel diamond bicycle frame
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	model/drawing revision/frame serial/size; nonmotorized diamond geometry and frame-only delivery; actual grade/heat/seam or seamless supply route/member part/butt profile and trim ends; lugs/shell/dropout material/angles/socket gaps; braze-on and bridge configuration; integral right hanger; qualified filler/flux batch/SDS/joint thermal practice and inspection; actual hearth fuel/energy and extraction; actual blast media/thin-wall compatibility, metal primer/colour/clearcoat formulations/electric bake/masking; complete finished frame net M kg/retained filler/finish and original calibrated weighing/independent stock mass closure; site/period/accepted frame count/rework/type/sample test allocation; current geometry/interface/test contract and upstream/identity gaps

4. Measurement and Unit Rules

rule_id	Applies to	Required property	Required unit	Rule
reference_mass	reference product	Mass 93a60a56-a3c8-11da-a746-0800200b9a66	kg	M = accepted net mass of one complete unit of the same configuration in kg; collect using cp_mass.
electricity_energy	cut_power; join_power; finish_power; inspection_power	Energy 93a60a56-a3c8-11da-a746-0800200c9a66	MJ	Meter actual kWh and multiply by3.6MJ/kWh; no rated power or assumed duty.
hearth_energy	hearth_gas	Energy 93a60a56-a3c8-11da-a746-0800200c9a66	MJ	Use contemporaneous measured site supplied fuel calorific value on a stated lower/higher heating-value basis with actual delivered volume/reference conditions and uncertainty. No generic gas density/LHV or2012Jiangsu project conversion.

5. System Boundary

Boundary Abstraction

Field	Value
declared_starting_condition	Received identified manufactured frame-member tubing, supplied lugs/shell/dropouts/bridge/fittings and actual filler/flux/coating/utility inputs; local member preparation, brazed frame build, actual finishing, interface acceptance and frame-only dispatch.
starting_condition_role	foreground_start
product_classification_scope	CPC3.0:49942; narrower standalone lug-brazed steel diamond frame
recursive_input_rule	Purchased tube butting/drawing/heat treatment and lug casting upstream. Bought complete frame cannot also be charged with its tubes/lugs or local joint work; finishing-only outside this route. Whole-cycle wheel/brake/drive/fork assembly is downstream, not frame material.
upstream_dataset_requirement	Compatible actual tube grade/profile/supply process, finished lug/shell/dropout parts, exact filler/flux/coating, utility/fuel, transport and treatment datasets with composition/property/state disclosures before extending foreground.
disclosure	Site/period and supplier scope, drawing/member/joining/finish/acceptance state, actual in-house versus bought operations, rework/sample-test attribution, missing upstream/support/transport/treatment; no automatic full cradle-to-gate.

rule_id	applies_to	rule	source_ids
boundary_tubing	prepare	Record each actual member grade/profile/length/end as one physical stock. Tubing may be supplied by different routes; do not infer seamless supply from butted geometry. At frame maker only actual trims/miter/forms included, not mandrel butting/smelting.	butting-frame-method; joining-frame-method
boundary_fittings	join	Exact upper/lower/seat lug, shell, distinct left/right dropout and each bridge/boss content declared. Whole purchased parts pool not a selected exchange; actual other cable guides/eyelets/pins/seat-clamp screws need separate specified rows if not contained.	mercian-frame-method
boundary_finish	finish	Include actual received wet primer/colour/clear formulation once including contained solvents; only separately added thinner/cleaner additional input. Retained dry film contributes M; actual solvent release/wet residue outside it. Metallic/candy/powder or gas-oven variants need new specific records, not alternative labels on this selected row.	mercian-frame-method
boundary_test	acceptance	Actual frame-only production checks and attributed type/sample tests with fixtures/support demand/rejects included. Fork/rider/running gear used temporarily in a test is support apparatus, not retained frame output; actual burden and reusable support allocation declared. Customer complete-cycle compliance not established by this frame foreground.

6. Process Inventory Structure

Process Map

process_id	process_name	inclusion	inclusion_condition	role	quantitative_reference
prepare	Received tube inspection, butt-aware cutting and miter preparation	required	Verify actual member grade/heat/profile and trim allowance; cut/miter/shape/drill and dry-fit to released geometry. Received tube butting is not local frame manufacture.	foreground_manufacturing	1kg accepted finished frame; conditional exchanges only where actual
join	Lugged frame alignment, brazing and braze-on completion	required	Fit actual supplied upper/lower/seat lugs, shell and distinct rear dropouts; align/pin/qualify gaps and braze with actual thermal/filler/flux procedure; add specified bridge/bosses and inspect joints/alignment.	foreground_manufacturing	1kg accepted finished frame; conditional exchanges only where actual
finish	Surface preparation, metal primer and electric-baked enamel	required	Actual flux removal, compatible conditional blasting, masking/primer/colour enamel/electric baking and conditional clear enamel; verify film/interface cleanliness. Exact chemicals and actual additions per supplier records, no universal duration or recipe.	foreground_manufacturing	1kg accepted finished frame; conditional exchanges only where actual
acceptance	Frame-only geometry/interface acceptance, weighing and dispatch	required	Record current frame serial/configuration, datum alignment/dropout spacing/thread-seat/braze/finish checks and actual attributable sample/type tests; independently weigh complete finished frame without fork/running gear.	foreground_manufacturing	1kg accepted finished frame; conditional exchanges only where actual

Process: Received tube inspection, butt-aware cutting and miter preparation (prepare)

Verify actual member grade/heat/profile and trim allowance; cut/miter/shape/drill and dry-fit to released geometry. Received tube butting is not local frame manufacture.

Inputs

Product flows

Supplied cold-worked chrome-moly steel bicycle top tube (top_tube)

One actual top tube grade/heat/part number/shape/end and wall profile, received kg and issue/return records. Trace butt location and trim allowance before local mitering; different grades/left-right specifications separate. Purchased tube forming/butting is upstream.

• Selected flow: Supplied cold-worked chrome-moly steel bicycle top tube
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_prepare.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_prepare
• Sources:

Supplied cold-worked chrome-moly steel bicycle down tube (down_tube)

One actual down tube grade/heat/part number/shape/end and wall profile, received kg and issue/return records. Trace butt location and trim allowance before local mitering; different grades/left-right specifications separate. Purchased tube forming/butting is upstream.

• Selected flow: Supplied cold-worked chrome-moly steel bicycle down tube
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_prepare.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_prepare
• Sources:

Supplied cold-worked chrome-moly steel bicycle seat tube (seat_tube)

One actual seat tube grade/heat/part number/shape/end and wall profile, received kg and issue/return records. Trace butt location and trim allowance before local mitering; different grades/left-right specifications separate. Purchased tube forming/butting is upstream.

• Selected flow: Supplied cold-worked chrome-moly steel bicycle seat tube
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_prepare.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_prepare
• Sources:

Supplied cold-worked chrome-moly steel bicycle head tube (head_tube)

One actual head tube grade/heat/part number/shape/end and wall profile, received kg and issue/return records. Trace actual constant-wall profile; different grades/left-right specifications separate. Purchased tube forming/butting is upstream.

• Selected flow: Supplied cold-worked chrome-moly steel bicycle head tube
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_prepare.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_prepare
• Sources:

Supplied cold-worked chrome-moly steel bicycle chainstay tube (chainstay)

One actual chainstay tube grade/heat/part number/shape/end and wall profile, received kg and issue/return records. Trace butt location and trim allowance before local mitering; different grades/left-right specifications separate. Purchased tube forming/butting is upstream.

• Selected flow: Supplied cold-worked chrome-moly steel bicycle chainstay tube
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_prepare.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_prepare
• Sources:

Supplied cold-worked chrome-moly steel bicycle seatstay tube (seatstay)

One actual seatstay tube grade/heat/part number/shape/end and wall profile, received kg and issue/return records. Trace butt location and trim allowance before local mitering; different grades/left-right specifications separate. Purchased tube forming/butting is upstream.

• Selected flow: Supplied cold-worked chrome-moly steel bicycle seatstay tube
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_prepare.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_prepare
• Sources:

Alternating current (cut_power)

Actual below1kV cut/miter/shape/drill/filing/fixture preparation demand, not tube-making energy charged locally.

• Selected flow: Alternating current 50657322-939c-4829-a87b-47c093bfa6a7
• Flow property / unit: Energy 93a60a56-a3c8-11da-a746-0800200c9a66 / MJ
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_prepare.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_prepare
• Sources:

Waste flows

Elementary flows

Outputs

Product flows

Waste flows

Low-alloy steel scrap (tube_scrap)

Actual separately collected clean low-alloy tube offcuts to recycling, measured kg after internal reuse; not mixed brazed/painted frame rejects.

• Selected flow: Low-alloy steel scrap ff8a3b67-c882-4ecb-9d95-bd7c8002497e
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_prepare.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_prepare
• Sources:

Elementary flows

Process: Lugged frame alignment, brazing and braze-on completion (join)

Fit actual supplied upper/lower/seat lugs, shell and distinct rear dropouts; align/pin/qualify gaps and braze with actual thermal/filler/flux procedure; add specified bridge/bosses and inspect joints/alignment.

Inputs

Product flows

Finished steel upper-head bicycle frame lug (upper_lug)

One actual supplied upper-head socket geometry/grade kg, angular fit and capillary-gap qualification; locally filed lug counted as supplied material plus actual work, not raw casting again.

• Selected flow: Finished steel upper-head bicycle frame lug
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Finished steel lower-head bicycle frame lug (lower_lug)

One supplied lower-head lug model/angle/interface kg; not interchangeable with upper lug, distinct grade or geometry separately recorded.

• Selected flow: Finished steel lower-head bicycle frame lug
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Finished steel bicycle seat-cluster lug (seat_lug)

One actual seat-cluster lug grade/socket/clamp interface kg; declare included seat-clamp hardware and do not add it twice.

• Selected flow: Finished steel bicycle seat-cluster lug
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Finished steel bicycle bottom-bracket shell (bb_shell)

One actual supplied shell material/thread/diameter/socket geometry kg. Bottom-bracket bearing/cartridge not part of frame-only output.

• Selected flow: Finished steel bicycle bottom-bracket shell
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Finished steel bicycle left rear dropout (left_dropout)

One actual left dropout grade/slot/interface kg; specified rear axle alignment to frame datum; right derailleur-hanger dropout separate.

• Selected flow: Finished steel bicycle left rear dropout
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Finished steel bicycle right rear dropout with integral derailleur hanger (right_dropout)

One actual right dropout grade/slot/hanger geometry kg; removable separate hangers outside this integral-hanger subset.

• Selected flow: Finished steel bicycle right rear dropout with integral derailleur hanger
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Finished steel bicycle rear brake bridge (brake_bridge)

One actual specified supplied bridge geometry kg and frame brake/mudguard interfaces. Whole brake assembly or building bridge not substitute.

• Selected flow: Finished steel bicycle rear brake bridge
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Finished steel threaded bicycle bottle-mount boss (bottle_boss)

Conditional one actual boss thread/grade kg, individually supplied and positioned to drawing. Cable guides/rack eyelets are distinct rows when installed, not a braze-on pool.

• Selected flow: Finished steel threaded bicycle bottle-mount boss
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Brass (brazing_rod)

One actual supplied uncoated copper-zinc brazing rod alloy/diameter/SDS kg qualified for these actual tubes/lugs. Public brass rod-material identity establishes no filler grade, recipe or temperature. Not silver solder, bronze or copper substituted.

• Selected flow: Brass e422cfbf-5444-43ab-a68a-22be82e2ad47
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Supplied borate-based bicycle-frame brazing flux powder (brazing_flux)

One actual dry formulated flux with identified SDS/chemistry and issue/return kg, supplier-qualified temperature range and residues; no universal borax purity assumed.

• Selected flow: Supplied borate-based bicycle-frame brazing flux powder
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Site-supplied gaseous natural gas for brazing hearth (hearth_gas)

Conditional actual gas-fired hearth only; independently meter delivered fuel energy MJ from actual volume/reference conditions and contemporaneous measured supplier calorific value. Source does not mandate this fuel; electric/other-fuel joins need distinct rows and actual records.

• Selected flow: Site-supplied gaseous natural gas for brazing hearth
• Flow property / unit: Energy 93a60a56-a3c8-11da-a746-0800200c9a66 / MJ
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Alternating current (join_power)

Actual below1kV joining support/alignment/fume-extraction energy; thermal fuel separate and actual outsourced supplied lugs upstream.

• Selected flow: Alternating current 50657322-939c-4829-a87b-47c093bfa6a7
• Flow property / unit: Energy 93a60a56-a3c8-11da-a746-0800200c9a66 / MJ
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Waste flows

Elementary flows

Outputs

Product flows

Waste flows

Elementary flows

Particulate matter, particle size unspecified (brazing_particle_air)

Only actual post-control immediate unspecified-air brazing/filing particulate sampling, unspecified size; exact Cu/Zn species or size fractions need separate identified atomic records, not this assumed PM quantity.

• Selected flow: Particulate matter, particle size unspecified 0ce3dedb-caca-407b-a856-a90470eb8ec0
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

carbon dioxide (fossil) (fossil_co2_air)

Only actual fossil hearth-fuel combustion evidenced by post-control measurement or current site fuel-carbon balance with fossil origin, retained carbon/incomplete combustion and actual exhaust boundary; immediate air unspecified. No borrowed gas emission factor.

• Selected flow: carbon dioxide (fossil) 08a91e70-3ddc-11dd-923d-0050c2490048
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_join.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_join
• Sources:

Process: Surface preparation, metal primer and electric-baked enamel (finish)

Actual flux removal, compatible conditional blasting, masking/primer/colour enamel/electric baking and conditional clear enamel; verify film/interface cleanliness. Exact chemicals and actual additions per supplier records, no universal duration or recipe.

Inputs

Product flows

Supplied cast-steel shot for bicycle-frame surface preparation (blast_media)

Conditional actual one shot grade/size distribution kg of makeup only, compatible thin-wall treatment; circulating shot transfer not fresh input. Alternative grit or sanding abrasive separate.

• Selected flow: Supplied cast-steel shot for bicycle-frame surface preparation
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_finish.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_finish
• Sources:

Supplied solvent-borne metal etch-primer formulation (etch_primer)

One actual specific metal etch primer SDS/binder/acid/solvent/colour kg, qualified to substrate/topcoat; not wall/cosmetic primer, no universal phosphoric-acid fraction.

• Selected flow: Supplied solvent-borne metal etch-primer formulation
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_finish.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_finish
• Sources:

Paint (Solvent-based) (colour_enamel)

One actual supplied solvent-borne alkyd colour stove-enamel formulation with supplier SDS/bake compatibility, issues/returns/retained dry film. No generic drying-rate or environmental-benefit claim from public comment adopted.

• Selected flow: Paint (Solvent-based) d8cbeec3-56d9-4b41-a5f6-6a754958182c
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_finish.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_finish
• Sources:

Paint (Solvent-based) (clear_enamel)

Conditional one actual separately supplied solvent-borne alkyd clear stove-enamel formulation kg; different from colour product with separate supplier/SDS/issue/film records. Contained solvent not also input separately.

• Selected flow: Paint (Solvent-based) d8cbeec3-56d9-4b41-a5f6-6a754958182c
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_finish.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_finish
• Sources:

Tap water (wash_water)

Conditional actual purchased municipal makeup product kg for flux removal/preparation. Actual cleaner/flux-contaminated outgoing wastewater separately identified; no water-resource exchange substituted.

• Selected flow: Tap water d1e0e36c-07f0-4a75-bdcb-efb5d9e2ac36
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_finish.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_finish
• Sources:

Alternating current (finish_power)

Actual below1kV shot/clean/spray/extraction/electric oven demand for this actual electric-bake subroute; gas oven/purchased heat must be added separately if actual.

• Selected flow: Alternating current 50657322-939c-4829-a87b-47c093bfa6a7
• Flow property / unit: Energy 93a60a56-a3c8-11da-a746-0800200c9a66 / MJ
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_finish.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_finish
• Sources:

Waste flows

Elementary flows

Outputs

Product flows

Waste flows

Waste paint (paint_residue)

Actual separated wet solvent-based colour-enamel overspray residue to declared treatment, measured kg and composition. Other primer/clearcoat/filter/cleaner residues separately recorded, not pooled.

• Selected flow: Waste paint 877e5a04-76c8-4c5b-ac4c-062f5beeb2bd
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_finish.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_finish
• Sources:

Spent steel-shot blasting residue (spent_shot)

Only actual spent steel-shot residue after internal recovery, identified oxide/flux/coating contamination and destination kg. Captured dust not air emission.

• Selected flow: Spent steel-shot blasting residue
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_finish.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_finish
• Sources:

Elementary flows

xylene (all isomers) (xylene_air)

Only actual post-control immediate-air total xylene CAS1330-20-7 species mass where current SDS and release sampling support it; all isomers, not p-xylene only, no presumed xylene constituent or VOC factor.

• Selected flow: xylene (all isomers) fe0acd60-3ddc-11dd-ad91-0050c2490048
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_finish.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_finish
• Sources:

Process: Frame-only geometry/interface acceptance, weighing and dispatch (acceptance)

Record current frame serial/configuration, datum alignment/dropout spacing/thread-seat/braze/finish checks and actual attributable sample/type tests; independently weigh complete finished frame without fork/running gear.

Inputs

Product flows

Alternating current (inspection_power)

Actual below1kV alignment/interface/finish inspection, attributed sample/type tests and complete-frame calibrated weighing equipment demand. No riding power.

• Selected flow: Alternating current 50657322-939c-4829-a87b-47c093bfa6a7
• Flow property / unit: Energy 93a60a56-a3c8-11da-a746-0800200c9a66 / MJ
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_acceptance.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_acceptance
• Sources:

Low-density polyethylene foil (PE-LD) (film)

Conditional actual noncellular nonadhesive protective film kg outside M; cartons/end protectors/fixtures individually added if present.

• Selected flow: Low-density polyethylene foil (PE-LD) 2cecd3a7-d90e-44b4-aec5-1d9dfb907477
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: Apply normalize_mass to q_item; reference_mass; cp_acceptance.
• Value mode: foreground_record
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow; collected per one accepted finished unit
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_acceptance
• Sources:

Waste flows

Elementary flows

Outputs

Product flows

Complete finished lug-brazed steel diamond bicycle frame (finished_machine)

1kg complete accepted frame-only output with specified brazed lugs/shell/dropouts/bridges/braze-ons and retained finish; actual net M excludes fork/headset/bottom-bracket cartridge/wheels/rider/packaging.

• Selected flow: Complete finished lug-brazed steel diamond bicycle frame
• Flow property / unit: Mass 93a60a56-a3c8-11da-a746-0800200b9a66 / kg
• Amount rule: 1 kg
• Value mode: fixed_value
• Specificity: site_specific
• Normalization basis: per 1 kg reference flow
• Basis kind: reference_flow
• Evidence kind: collected_record
• Collection protocol: cp_mass
• Sources:

Waste flows

Elementary flows

7. Allocation and Co-product Handling

rule_id	applies_to	rule	source_ids
allocation_direct	all processes	Attribute actual member/part issue-return-stock and measured utility demand to drawing/size/grade/finish-specific work orders and matched accepted frame count. Include actual rework/rejects and sample-test burden. Different frame sizes/configurations not mixed under one mean M without disclosed stratification.
allocation_shared	shared operations	Separate operations first. If inseparable, document causal actual cutting/joining/fixture occupancy, sprayed area/bake rack occupancy and inspection/test demand. Reconcile totals and assess alternative drivers; fixed frame setup/inspection not automatically proportional to net frame kg.
allocation_scrap	waste	Separate internal stock/shot reuse, outgoing clean offcuts, brazed/painted rejects, flux/wet-paint residues and genuine co-products. No automatic avoided steel/paint credit or3% assumed scrap factor. Economic allocation only with actual co-product and no causal physical basis, actual price period and sensitivity.

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_mass	acceptance	accepted complete output	measurement	model; configuration; serial number; accepted net mass M	Use traceable weighing records for the accepted complete unit of the same configuration.	kg	every accepted finished frame	matched manufacturing/acceptance period	actual complete frame weighing station	accepted net mass per unit	calibrated complete frame readings/tare; no fork/running gear/support load/packaging; independent retained-member/filler/finish mass balance
cp_prepare	prepare	independent atomic exchanges	foreground_record	drawing/grade/heat/member/butt profile/trim end; received and issued-returned kg; cut/miter geometry; meters; low-alloy offcuts	Record each actual exchange separately with identified supplier issues/returns and independent stock/part kg, calibrated utility meters, actual site supplied fuel calorimetry/reference volume, or post-control species sampling/exhaust/time. Record model/drawing/size/grade/finish configuration, work orders, stock/rework, matched same-configuration accepted count and waste destination.	kg; MJ	per batch/unit/test and full period	same configuration manufacturing/acceptance cycle	actual manufacturing/test site and declared subcontractors	attributable process exchange / accepted units	supplier grade/profile/part/SDS contents; calibration/sampling/calorimetry uncertainty; stock/accepted count closure
cp_join	join	independent atomic exchanges	foreground_record	lug/shell/left-right dropout/bridge/boss fit-list and supplier contents; actual kg; socket gap/datum/pin; filler/flux/SDS and thermal procedure; current fuel calorimetry/meter; joint/alignment and actual exhaust samples	Record each actual exchange separately with identified supplier issues/returns and independent stock/part kg, calibrated utility meters, actual site supplied fuel calorimetry/reference volume, or post-control species sampling/exhaust/time. Record model/drawing/size/grade/finish configuration, work orders, stock/rework, matched same-configuration accepted count and waste destination.	kg; MJ	per batch/unit/test and full period	same configuration manufacturing/acceptance cycle	actual manufacturing/test site and declared subcontractors	attributable process exchange / accepted units	supplier grade/profile/part/SDS contents; calibration/sampling/calorimetry uncertainty; stock/accepted count closure
cp_finish	finish	independent atomic exchanges	foreground_record	exact media/cleaner/primer/colour/clear SDS and issue-return-stock/film; actual water/meter/electric bake; species/exhaust/time and distinct waste masses	Record each actual exchange separately with identified supplier issues/returns and independent stock/part kg, calibrated utility meters, actual site supplied fuel calorimetry/reference volume, or post-control species sampling/exhaust/time. Record model/drawing/size/grade/finish configuration, work orders, stock/rework, matched same-configuration accepted count and waste destination.	kg; MJ	per batch/unit/test and full period	same configuration manufacturing/acceptance cycle	actual manufacturing/test site and declared subcontractors	attributable process exchange / accepted units	supplier grade/profile/part/SDS contents; calibration/sampling/calorimetry uncertainty; stock/accepted count closure
cp_acceptance	acceptance	independent atomic exchanges	foreground_record	serial/drawing/size/complete frame-only inclusion; original geometry/interface/test results and accepted/reject/tested count/period; calibrated net readings/tare and independent finished frame mass balance	Record each actual exchange separately with identified supplier issues/returns and independent stock/part kg, calibrated utility meters, actual site supplied fuel calorimetry/reference volume, or post-control species sampling/exhaust/time. Record model/drawing/size/grade/finish configuration, work orders, stock/rework, matched same-configuration accepted count and waste destination.	kg; MJ	per batch/unit/test and full period	same configuration manufacturing/acceptance cycle	actual manufacturing/test site and declared subcontractors	attributable process exchange / accepted units	supplier grade/profile/part/SDS contents; calibration/sampling/calorimetry uncertainty; stock/accepted count closure

Calculation Rules

rule_id	Applies to	Formula or rule	Inputs	Output	source_ids
normalize_mass	top_tube; down_tube; seat_tube; head_tube; chainstay; seatstay; cut_power; tube_scrap; upper_lug; lower_lug; seat_lug; bb_shell; left_dropout; right_dropout; brake_bridge; bottle_boss; brazing_rod; brazing_flux; hearth_gas; join_power; brazing_particle_air; fossil_co2_air; blast_media; etch_primer; colour_enamel; clear_enamel; wash_water; finish_power; paint_residue; spent_shot; xylene_air; inspection_power; film	q_ref = q_item / M; q_item = exchange amount per one accepted finished unit; q_ref = exchange amount per 1 kg reference flow.	q_item; M; cp_mass	q_ref

q_item is actual attributed process exchange after measured issues/returns/stock/reclaim/rework divided by matched complete accepted frame count. M is independently measured for the same finished frame-only configuration. Preserve kg or MJ numerator; actual supplied lugs/shell/dropouts/rods kg, with counts supplementary. Count/area/volume conversions need contemporaneous same-part physical mass/profile or actual gas state/calorimetry and uncertainty. No catalogue frame/frame-plus-fork mass, density, tube-kit theoretical mass, rider load, assumed gas LHV or percentage scrap.

Data Quality Requirements

requirement_id	Applies to	Requirement	Evidence
quality_weighing	finished_machine	Weigh the complete accepted finished frame with all permanently retained specified fittings, filler and dry coating using a calibrated appropriate-capacity instrument and controlled support/fixture tare. Exclude fork/headset/BB cartridge/wheels/rider/test loads/loose accessories/packaging; no frame-plus-fork catalogue mass. Retain serial/geometry/finish state, original readings/date/instrument/calibration/repeats/uncertainty. Independently reconcile received retained tube/part masses, trim/filing losses, retained filler and cured coating against M. Missing physical originals block dataset use.	original complete-frame net weighing and independent retained mass balance
quality_members	prepare; join	Trace each member grade/heat/shape/wall/butt profile/end mark and received supply route. Preserve sufficient actual qualified thick-end joint length after trimming; use supplier profile and released drawing, no universal butt length/wall/density/strength. Head tube, front triangle and distinct left/right stays not a mixed tube set. Tube-maker seamless/welded/mandrel/heat treatment not presumed local.	reynolds-frame-method; joining-frame-method; butting-frame-method; actual member drawings
quality_joining	join	Require actual matched tube/lug/shell/dropout geometry, capillary gap, datum/pinning and qualified filler/flux/thermal procedure with traceable temperature/time observations and inspections where required by the released plan. Actual overheating/misalignment/rework recorded. Brass rod identity is not a universal recommendation. Joining-sensitive heat-treated/silver-only grades, TIG wire/flux-cored wire and titanium/stainless not interchangeable. Supplier joining FAQ is grade-specific guidance, not legal certification or numeric factory pass thresholds.	joining-frame-method; mercian-frame-method; current qualified joint procedure/results
quality_geometry	join; acceptance	Verify actual frame-datum geometry and alignment, head/seat tube and shell axes, rear dropout parallelism/spacing, integral hanger alignment, specified bridge/brake and braze-on positions. Inspect actual shell/head/seat thread/fit interfaces and remove coating intrusions without assuming fitted headset/BB. Current contractual frame-only test plan/results, sampled configuration/count/period/instruments/fixtures/reject attribution required; no imported rider load, fatigue cycles, riding life or whole-cycle compliance claim.	mercian-frame-method; current frame geometry and inspection/test originals
quality_finish	finish	Trace actual metal etch primer, one colour enamel and optional one clear enamel chemistry/SDS/supplier batches and actual compatibility/cure schedule with cold-worked substrate/braze. Record masking, dry film/adhesion/appearance and interface cleanliness under current specifications. Blasting only actual approved media/thin-wall method; no presumed steel shot, universal blast pressure, coating thickness, four-week painting duration, recipe or environmental superiority. Received solvents inside paint counted once; actual additions/species separately.	mercian-frame-method; actual SDS/cure/masking and film records
quality_identity	all flows	Actual public property/unit/state retained. Broad bicycle-parts or unfinished/spectacle-frame identity cannot establish exact finished bicycle-frame output. Project-specific2012NGCC gas/density/LHV not frame-maker fuel; flux Volume not powder kg. Brass rod and solvent-based paint qualify one actual formulation/supplied form, not all filler/resin choices. Low-alloy scrap uses actual clean measured offcuts, not3% example. Cast-steel shot/non-ferrous-ore and mixed spent abrasive/non-metal classes remain unresolved, not rewritten.	public flow/property/unit chain and actual supplier qualification
quality_release	elementary	Only actual post-control particulate mass with unspecified size/air subcompartment, actual fossil CO2 origin/site carbon balance, or actual total xylene CAS1330-20-7 immediate-air species supported by current chemical/SDS/exhaust observations. No obligatory emissions, total VOC substituted as xylene, NOx guessed as NO2, fuel upstream emission as factory release or captured dust as air. Any actual metal/boron/fluoride/size species and actual wastewater/sludge separately identified with correct medium/property and measurements.	original post-control sampling/exhaust/time and current fuel/SDS balances
quality_coverage	dataset	Close full actual member/part/chemical/meter/stock/test inventory. Add actual separate cable guides, eyelets, braze-on bosses/pins/clamp hardware, cleaners/added solvents/masking tape/decals/clearcoat or other finishes, captured dust, contaminated flux/shot/sludge/filters and packaging when present and not contained. Different grades/left-right parts/paint formulations each separate atomic row and protocol. Preserve measured/calculated/estimated/missing/excluded/not-applicable status and uncertainty, disclose upstream stock/component/transport/support/treatment gaps; no pooled parts or claim of complete cradle-to-gate.	complete actual frame BOM, supplier SDS/contents and stock/meter closure

9. Validation Rules

rule_id	applies_to	rule	source_ids
validation_reference	finished_machine	Exactly1kg complete accepted finished frame-only output; reference name equals finished_machine name. Candidate blank UUID only with precise registered gap. Require original cp_mass actual M kg and independent retained tube/part/filler/film closure. Formula/schema pass does not establish physical data or scientific approval.
validation_basis	inventory	Verify stable lowercase row/rule/protocol links, same-size/grade/finish accepted frame count, actual kg/MJ numerator and normalize_mass. Reject frameset/whole-bike/rider/mixed configuration denominators and catalogue/density/project gas conversions.
validation_scope	dataset	Verify actual local member preparation and qualified lug-brass joining, declared supplied tube/lug scope, wet electric-baked finish and independent frame-only acceptance/dispatch. Whole bike/fork/suspension/welded/carbon/powered/repair and finishing-only routes require other applicable methodology, not this identity.
validation_release	elementary	Exact measured species/origin/immediate-air medium and conditional quantity. Technosphere tap water, resource abstraction, actual contaminated wastewater, captured solid residue/treatment and direct air species remain separate.

10. Published Dataset Profile

Field	Value
dataset_role	foreground_manufacturing_module
downstream_use	secondary_dataset; background_dataset
allowed_use	Manufacture of a new standalone finished diamond frame for a nonmotorized bicycle, using identified cold-worked non-stainless chrome-moly steel tube members, supplied steel socket lugs/bottom-bracket shell/rear dropouts, qualified uncoated copper-zinc filler and formulated brazing flux. Scope starts at received manufactured tubes and components, includes local cut/trim/miter/fit/alignment and lug brazing, specified braze-ons, actual cleaning/surface preparation, spray-applied metal etch primer and solvent-borne alkyd colour stove-enamel with actual electric baking, conditional clear enamel, final interface/geometry/finish acceptance and independent frame-only dispatch. Actual matched grade/butt profile/socket/joining/finish qualification and released drawings govern; no universal material recipe or Mercian brand specification is mandated.
excluded_use	Exclude complete bicycles and riding/service outputs, frame-and-fork sets, forks/headsets/bottom-bracket cartridges/wheels/brakes/transmission, wheelchair components, motorized/e-bike/motorcycle frames, aluminium/titanium/carbon/stainless frames, suspension/step-through/folding/tandem structures, TIG-welded or lugless fillet-only frames, uncoated intermediate-only outputs, bought-complete-frame finishing-only routes, repair/restoration and upstream tube butting/steelmaking/lug casting. Heat-treated or joining-sensitive grades requiring different qualified filler/thermal practice are outside this cold-worked brass-lug subroute. Customer complete-bike assembly, use/maintenance and end of life excluded. Attributable actual factory inspection/type/sample testing included; foreground alone is not full cradle-to-gate or proof of riding performance/life.
required_metadata	model/drawing revision/frame serial/size; nonmotorized diamond geometry and frame-only delivery; actual grade/heat/seam or seamless supply route/member part/butt profile and trim ends; lugs/shell/dropout material/angles/socket gaps; braze-on and bridge configuration; integral right hanger; qualified filler/flux batch/SDS/joint thermal practice and inspection; actual hearth fuel/energy and extraction; actual blast media/thin-wall compatibility, metal primer/colour/clearcoat formulations/electric bake/masking; complete finished frame net M kg/retained filler/finish and original calibrated weighing/independent stock mass closure; site/period/accepted frame count/rework/type/sample test allocation; current geometry/interface/test contract and upstream/identity gaps
required_quality_disclosure	Candidate; scientific review pending. Original frame-only net M/uncertainty/retained mass closure, current tube butt/trim/grade/supplier route and qualified joining/geometry/interfaces/finish, actual counts/site/test period/rework/support allocation, chemical/fuel properties and species measurements, unresolved identities/upstream/transport/treatment coverage. Per-kg frame manufacturing not equal riding/service performance or approved cradle-to-gate.
update_trigger	Tube/member/grade/butt/supply, geometry/lugs/thermal/filler/flux/braze-ons/dropout, primer/enamel/cure, site/period/test/accepted state, new identities/evidence.

11. Data Sources

Source id	Type	Reference	Used for
mercian-frame-method	handbook	Mercian, Our Craft, undated official HTML, Skilled Traditional Bespoke / Precision Brazing / Final Frame Details / painting / Crafted Checked Complete; unpaginated. https://www.merciancycles.co.uk/our-craft	Illustrative hand lug-brazing/alignment, specified fittings, preparation/etch-primer/baked finish and final frame interface inspection. No compulsory brand/grade, filler/fuel/alkyd formulation/electric oven, paint duration, life or environmental comparison; actual current supplier/thermal/finish records required.
reynolds-frame-method	handbook	Reynolds Technology, 525 Cold-Worked Chrome-Moly Steel, undated official supplier page, material/use sections; unpaginated. https://www.reynoldstechnology.biz/materials/steel/s-525/	Cold-worked alloy/butted member and cutting/mitering context only; not proof of the illustrated Mercian grade, current stock availability, numeric density/UTS or service-life/fatigue equivalence. Actual member profile/grade supplied records govern.
joining-frame-method	handbook	Reynolds Technology, Welding and Joining supplier FAQ, undated, joining methods/butt-profile trimming/filler supply; unpaginated. https://www.reynoldstechnology.biz/faqs-on-reynolds-steel-tubing/welding-and-joining/	Grade-dependent joining compatibility and butt-aware trim; rejects assuming one filler/thermal method for every steel. Historical531/753 examples limited to stated historical/grade context. No ER70 TIG wire as brazing rod, universal trim length or current conformity inferred.
butting-frame-method	handbook	Reynolds Technology, How is butted tubing made?, undated official supplier description, supply routes and Mandrel Press; unpaginated. https://www.reynoldstechnology.biz/materials/how-butted-tubing-is-made/	Explains supplied profile generation and seamless-versus-welded alternatives upstream; requires actual supply-route/butt tracing. No billet dimensions/heat temperature/density or assumption that these tube-making processes occur at frame site.