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exported equivalent COPI_0000377
Wellhead
IRI: https://www.inf.ufrgs.br/ontologies/copi/COPI_0000377
Generated onGerado em 2026-04-15
Natural Language DefinitionDefinição em Linguagem Natural
EN
A wellhead is an assembly that bears a well surface control function and provides the structural and control interface between a wellbore and surface equipment.
PT-BR
Um cabeçal de poço é um conjunto que porta uma função de controle superficial do poço e fornece a interface estrutural e de controle entre um poço e os equipamentos de superfície.
Formal AxiomsAxiomas Formais
Semi-formal (Aristotelian)Semi-formal (Aristotélico)
Every wellhead is an assembly that bears a well surface control function and has component parts including casing hangers and connection to wellbore
First-Order Logic TheoryTeoria em Lógica de Primeira Ordem
[Definition]∀x (Wellhead(x) ↔ Assembly(x) ∧ ∃f (WellSurfaceControlFunction(f) ∧ bearerOf(x,f)) ∧ ∃bearerOf.WellSurfaceControlFunction ⊓ ∃hasComponentPartAtAllTimes.CasingHanger ⊓ ∃hasConnectionTo.Wellbore) — Steps 1–3: genus + identity-giving function [Function axiom: WellSurfaceControlFunction]∀f (WellSurfaceControlFunction(f) → ∀p (realizedIn(f,p) → WellSurfaceControlProcess(p)) ∧ ∃p (WellSurfaceControlProcess(p) ∧ realizedIn(f,p))) — Step 1: ∀ preserves type-type identity; ∃ rules out vacuous functions never realised [Necessary part: WellheadSpool]∀x (Wellhead(x) → ∃p (WellheadSpool(p) ∧ hasComponentPartAtAllTimes(x,p))) — Step 4: mereological commitment — every instance must have this part [Process participation signature]∀x ∀f ((Wellhead(x) ∧ WellSurfaceControlFunction(f) ∧ bearerOf(x,f)) → ∃m (WellFluid(m) ∧ participatesIn(m,f)) ∧ ∃e (WellFluid(e) ∧ participatesIn(e,f)) ∧ processType(f,FlowRegulation)) — Step 5: typed participants in the realising process
OWL 2 / Turtle
@prefix copi: <https://www.inf.ufrgs.br/ontologies/copi/> . @prefix : <https://www.inf.ufrgs.br/ontologies/copi/> . @prefix owl: <http://www.w3.org/2002/07/owl#> . @prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> . @prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> . @prefix xsd: <http://www.w3.org/2001/XMLSchema#> . @prefix bfo: <http://purl.obolibrary.org/obo/> . @prefix iof-core: <https://spec.industrialontologies.org/ontology/construct/> . @prefix iof-av: <https://spec.industrialontologies.org/ontology/annotation/> . @prefix skos: <http://www.w3.org/2004/02/skos/core#> . @prefix qudt: <http://qudt.org/schema/qudt/> . @prefix dcterms: <http://purl.org/dc/terms/> . @prefix foaf: <http://xmlns.com/foaf/0.1/> . @prefix apv: <http://inf.ufrgs.br/ontologies/apv#> . ### COPI — Core Ontology for Petroleum Installations ### Class module: Wellhead <https://www.inf.ufrgs.br/ontologies/copi> rdf:type owl:Ontology ; dcterms:title "Core Ontology for Petroleum Installations (COPI)"@en ; dcterms:title "Ontologia Core para Instalações de Petróleo (COPI)"@pt-br ; dcterms:description "BFO/IOF-Core conformant ontology of equipment classes for petroleum production plants, developed using the five-step RDL enrichment method."@en ; skos:scopeNote "Material artifacts (bfo:material_entity) that (i) are part of a petroleum production plant, and (ii) bear at least one function whose realization involves the transport (e.g. production and injection), processing (separation and other processes), control, monitoring, measurement, containment or offloading of material or energy."@en ; skos:scopeNote "Artefatos materiais (bfo:material_entity) que (i) fazem parte de uma planta de produção de petróleo, e (ii) possuem ao menos uma função cuja realização envolve o transporte (p. ex. produção e injeção), processamento (separação e outros processos), controle, monitoramento, medição, contenção ou escoamento de material ou energia."@pt-br ; skos:scopeNote "COPI provides high-level equipment categories defined by function to demonstrate the defined-class mechanism. Equipment subtypes are annotated with references to CFIHOS and PCA RDL terms. COPI is not a reference data library; organizations should use CFIHOS, PCA RDL, or ISO 14224 for comprehensive equipment classification."@en ; skos:scopeNote "COPI fornece categorias de alto nível de equipamentos definidas por função para demonstrar o mecanismo de classe definida. Os subtipos de equipamentos são anotados com referências aos termos do CFIHOS e do PCA RDL. COPI não é uma biblioteca de dados de referência; organizações devem utilizar o CFIHOS, o PCA RDL ou a ISO 14224 para classificação abrangente de equipamentos."@pt-br ; owl:versionInfo "1.1.0-104-g4d16eff" ; owl:imports <https://spec.industrialontologies.org/ontology/core/Core/> ; owl:imports <http://purl.obolibrary.org/obo/bfo/2020/bfo.owl> ; dcterms:creator "Nicolau Oyhenard dos Santos"@en ; dcterms:contributor "Cauã Antunes" ; dcterms:contributor "Haroldo Rojas" ; dcterms:contributor "Rafael Petry" ; dcterms:contributor "Régis Romeu" ; dcterms:contributor "Mara Abel" ; dcterms:isPartOf <https://inf.ufrgs.br/projetos/OntoKG> ; dcterms:publisher "Universidade Federal do Rio Grande do Sul (UFRGS)"@en ; dcterms:license <https://creativecommons.org/licenses/by/4.0/> ; dcterms:created "2026-04-08"^^xsd:date ; dcterms:modified "2026-07-13"^^xsd:date ; apv:GlobalMinLanguageCoverage "en pt-br" ; apv:ClassURIFormationRule "https://www[.]inf[.]ufrgs[.]br/ontologies/copi/(COPI_[0-9]{7}|[A-Z][A-Za-z0-9]*)" ; apv:ClassMinAnnotationCoverage "rdfs:label https://spec.industrialontologies.org/ontology/annotation/naturalLanguageDefinition" . iof-av:naturalLanguageDefinition rdf:type owl:AnnotationProperty ; apv:MinAnnotationLength 20 . ### Identity-giving function :WellSurfaceControlFunction rdf:type owl:Class ; rdfs:subClassOf iof-core:DesignedFunction ; rdfs:subClassOf [ rdf:type owl:Restriction ; owl:onProperty bfo:BFO_0000054 ; # realizedIn owl:allValuesFrom :WellSurfaceControlProcess ] ; rdfs:subClassOf [ rdf:type owl:Restriction ; owl:onProperty bfo:BFO_0000054 ; # realizedIn owl:someValuesFrom :WellSurfaceControlProcess ] ; rdfs:label "well surface control function"@en ; rdfs:label "função de controle de superfície do poço"@pt-br . ### Process type :WellSurfaceControlProcess rdf:type owl:Class ; rdfs:subClassOf iof-core:PlannedProcess ; rdfs:label "well surface control process"@en ; rdfs:label "processo de controle de superfície do poço"@pt-br . :WellSurfaceControlProcess rdfs:subClassOf [ rdf:type owl:Restriction ; owl:onProperty iof-core:hasInput ; owl:someValuesFrom :WellFluid ] ; rdfs:subClassOf [ rdf:type owl:Restriction ; owl:onProperty iof-core:hasSpecifiedOutput ; owl:someValuesFrom :WellFluid ] . ### Equipment universal: Wellhead :Wellhead rdf:type owl:Class ; owl:equivalentClass [ rdf:type owl:Class ; owl:intersectionOf ( iof-core:Assembly [ rdf:type owl:Restriction ; owl:onProperty iof-core:hasFunction ; # Object branch (MaterialArtifact/Assembly/Object/FiatObjectPart) owl:someValuesFrom :WellSurfaceControlFunction ] [ rdf:type owl:Restriction ; owl:onProperty iof-core:hasComponentPartAtAllTimes ; owl:someValuesFrom :WellheadSpool ] ) ] ; rdfs:label "wellhead"@en ; rdfs:label "cabeçal de poço"@pt-br ; iof-av:naturalLanguageDefinition "A wellhead is an assembly that bears a well surface control function and provides the structural and control interface between a wellbore and surface equipment."@en ; skos:definition "A wellhead is an assembly that bears a well surface control function and provides the structural and control interface between a wellbore and surface equipment."@en ; iof-av:naturalLanguageDefinition "Um cabeçal de poço é um conjunto que porta uma função de controle superficial do poço e fornece a interface estrutural e de controle entre um poço e os equipamentos de superfície."@pt-br ; iof-av:semiFormalNaturalLanguageAxiom "Every wellhead is an assembly that bears a well surface control function and has component parts including casing hangers and connection to wellbore"@en ; iof-av:firstOrderLogicAxiom "∀x(Wellhead(x) ↔ Assembly(x) ∧ ∃f(WellSurfaceControlFunction(f) ∧ bearerOf(x,f)) ∧ ∃h(CasingHanger(h) ∧ hasComponentPartAtAllTimes(x,h)) ∧ ∃w(Wellbore(w) ∧ hasConnectionTo(x,w)))"@en ; :WellheadSpool rdf:type owl:Class ; rdfs:subClassOf iof-core:MaterialArtifact ; rdfs:label "spool de cabeçal de poço"@pt-br ; rdfs:label "wellhead spool"@en . # Disjointness: Wellhead and Separator [] rdf:type owl:AllDisjointClasses ; owl:members ( :Wellhead :Separator ) . # Disjointness: Wellhead and HeatExchanger [] rdf:type owl:AllDisjointClasses ; owl:members ( :Wellhead :HeatExchanger ) . # Disjointness: Wellhead and Compressor [] rdf:type owl:AllDisjointClasses ; owl:members ( :Wellhead :Compressor ) .
Axiomatization Decision LogRegistro de Decisões
1 Identity-Giving FunctionFunção Identitária
Function class
WellSurfaceControlFunction ⊑ DesignedFunction
Realized in
WellSurfaceControlProcess ⊑ PlannedProcess
The wellhead's identity-giving function is to provide surface control of well operations - pressure control, flow control, mounting for other equipment like Christmas trees, and serving as the interface between subsurface and surface systems. This is distinct from the WellFluidControlFunction of Christmas trees which focuses on production flow control.
2 Genus DeterminationDeterminação do Gênero
Assemblybfo:Object (BFO_0000030)
Wellhead is clearly an assembly of multiple physically connected components (spools, valves, adapters, hangers, housings) that function as a causally unified unit with a single maintainable boundary. It's more complex than a simple MaterialArtifact but exists as one integrated Object. No domain-specific superclass exists in the parent candidates that would be more appropriate.
3 Differentia SpecificaDiferença Específica
∃bearerOf.WellSurfaceControlFunction ⊓ ∃hasComponentPartAtAllTimes.CasingHanger ⊓ ∃hasConnectionTo.Wellbore

A wellhead bears a well surface control function, incorporates casing hangers for wellbore termination, and provides connection to the wellbore.

The functional differentia (WellSurfaceControlFunction) captures the primary identity-giving role. The structural differentia (casing hangers) and relational differentia (connection to wellbore) are essential characteristics that distinguish wellheads from other assemblies - all wellheads must interface with the wellbore and incorporate hangers for casing/tubing.
4 Necessary PartsPartes Necessárias
Part classParentRelation
WellheadSpoolMaterialArtifacthasComponentPartAtAllTimes
These parts represent the minimal necessary components for any wellhead to fulfill its surface control function - wellbore interface (casing hanger), structural integrity (spool/body), and safety (pressure containment).
Process Participation SignatureAssinatura de Participação em Processo
InputsEntradas
{'type': 'WellFluid', 'count': 1, 'constraints': 'from wellbore, various phases and pressures'}
OutputsSaídas
{'type': 'WellFluid', 'count': 1, 'constraints': 'controlled pressure and flow to surface equipment'}
TransformationTransformação
pressure and flow control without phase change
Wellhead receives well fluids from the wellbore and provides controlled interface to surface equipment. The transformation is control-based rather than thermodynamic or chemical.
Disjoint WithDisjunto com
Separator HeatExchanger Compressor
C2: Compressor. C4: Separator, HeatExchanger. Wellhead provides well control interface function which is incompatible with separation processes, heat transfer processes, or compression processes that change fluid properties
MetadataMetadados
COPI IDCOPI IDCOPI_0000377
IRIIRIhttps://www.inf.ufrgs.br/ontologies/copi/COPI_0000377
StatusStatusexported
Axiom modeModoequivalent
CreatedCriado2026-04-15
UpdatedAtualizado2026-06-28
LLM modelModelo LLMclaude-sonnet-4-20250514
VersionVersão2026-07-13
Quick factsDados rápidos
GenusGêneroAssembly
Root classClasse raizAssembly
Axiom modeModoequivalent
FunctionFunçãoWellSurfaceControlFunction
ProcessProcessoWellSurfaceControlProcess
PartsPartes1
Source DefinitionsDefinições nas Fontes 4 sources
ISO 15926-4 WELLHEAD
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CFIHOS wellhead
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SLB Glossary wellhead
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ONEPETRO_GLOSSARY Wellhead
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