exported
necessary
shaft
IRI:
http://www.inf.ufrgs.br/ontologies/copi#Shaft
Generated on 2026-05-04
Natural Language Definition
EN
An Assembly that bears a PowerTransmissionFunction and that has component parts including shaft keys for torque transmission and shaft seals for leakage prevention, serving as the core rotating element in rotating machinery.
PT-BR
Um Assembly que porta uma PowerTransmissionFunction e que possui partes componentes incluindo chavetas de eixo para transmissão de torque e vedações de eixo para prevenção de vazamento, servindo como o elemento rotativo central em máquinas rotativas.
Formal Axioms
Semi-formal (Aristotelian)
Every shaft is an assembly that transmits power through rotation and has shaft keys, shaft seals, and shaft sleeves as essential components.
First-Order Logic Theory
Loading…
▸ Stored override
∀x(Shaft(x) → Assembly(x) ∧ ∃f(PowerTransmissionFunction(f) ∧ bearerOf(x,f)) ∧ ∃k(ShaftKey(k) ∧ hasComponentPartAtAllTimes(x,k)) ∧ ∃s(ShaftSeal(s) ∧ hasComponentPartAtAllTimes(x,s)) ∧ ∃l(ShaftSleeve(l) ∧ hasComponentPartAtAllTimes(x,l)))
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: Shaft
<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" ;
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 "2026-10-08"^^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
:COPI_0000192 rdf:type owl:Class ; # PowerTransmissionFunction
rdfs:subClassOf iof-core:DesignedFunction ;
rdfs:subClassOf [
rdf:type owl:Restriction ;
owl:onProperty bfo:BFO_0000054 ; # realizedIn
owl:allValuesFrom :COPI_0000604 # PowerTransmissionProcess
] ;
rdfs:subClassOf [
rdf:type owl:Restriction ;
owl:onProperty bfo:BFO_0000054 ; # realizedIn
owl:someValuesFrom :COPI_0000604 # PowerTransmissionProcess
] ;
rdfs:label "power transmission function"@en ;
rdfs:label "função de transmissão de potência"@pt-br ;
iof-av:naturalLanguageDefinition "A DesignedFunction that is realized in a PowerTransmissionProcess and that consists in the capacity to transmit mechanical energy from a prime mover through rotational motion or to generate energy when acting as a driven element."@en ;
skos:definition "A DesignedFunction that is realized in a PowerTransmissionProcess and that consists in the capacity to transmit mechanical energy from a prime mover through rotational motion or to generate energy when acting as a driven element."@en .
### Process type
:COPI_0000604 rdf:type owl:Class ; # PowerTransmissionProcess
rdfs:subClassOf iof-core:PlannedProcess ;
rdfs:label "power transmission process"@en ;
rdfs:label "processo de transmissão de potência"@pt-br ;
iof-av:naturalLanguageDefinition "A PlannedProcess in which mechanical energy is transmitted through rotational motion from one component to another via a rotating shaft, enabling the transfer of torque and angular velocity to mounted components."@en ;
skos:definition "A PlannedProcess in which mechanical energy is transmitted through rotational motion from one component to another via a rotating shaft, enabling the transfer of torque and angular velocity to mounted components."@en .
### Equipment universal: Shaft
:COPI_0000346 rdf:type owl:Class ; # Shaft
rdfs:subClassOf iof-core:Assembly ;
rdfs:subClassOf [
rdf:type owl:Restriction ;
owl:onProperty iof-core:hasFunction ; # Object branch (MaterialArtifact/Assembly/Object/FiatObjectPart)
owl:someValuesFrom :COPI_0000192 # PowerTransmissionFunction
] ;
rdfs:label "shaft"@en ;
rdfs:label "eixo"@pt-br ;
iof-av:naturalLanguageDefinition "An Assembly that bears a PowerTransmissionFunction and that has component parts including shaft keys for torque transmission and shaft seals for leakage prevention, serving as the core rotating element in rotating machinery."@en ;
skos:definition "An Assembly that bears a PowerTransmissionFunction and that has component parts including shaft keys for torque transmission and shaft seals for leakage prevention, serving as the core rotating element in rotating machinery."@en ;
iof-av:naturalLanguageDefinition "Um Assembly que porta uma PowerTransmissionFunction e que possui partes componentes incluindo chavetas de eixo para transmissão de torque e vedações de eixo para prevenção de vazamento, servindo como o elemento rotativo central em máquinas rotativas."@pt-br ;
iof-av:isPrimitive "true"^^xsd:boolean ;
iof-av:primitiveRationale "Constructive classification based on physical structure. Under OWA, sufficient conditions for shaft identity could lead to false positives - any assembly with a shaft key and rotational motion might be classified as a shaft rather than a more specific equipment type that contains a shaft. The structural differentia provides necessary conditions while allowing domain experts to validate sufficiency."@en ;
rdfs:subClassOf [ rdf:type owl:Restriction ; owl:onProperty bfo:BFO_0000196 ; owl:someValuesFrom :COPI_0000059 ] ;
skos:definition "[ISO 15926-4] A <SHAFT> is an <ENGINE COMPONENT> that is the core rotating element on which the rotating parts are mounted and through which energy is either transmitted from the prime mover or generated in case of a driver."@en .
Axiomatization Decision Log
1
Identity-Giving Function
Function class
PowerTransmissionFunction
⊑ DesignedFunction
Realized in
PowerTransmissionProcess
⊑ PlannedProcess
The shaft's identity-giving function is power transmission - it is designed to transmit energy 'from the prime mover or generated in case of a driver'. This is the fundamental purpose that makes a shaft a shaft rather than just any rotating component. PowerTransmissionFunction already exists in the ontology (used by gearbox) and captures this essential function.
2
Genus Determination
Assembly
bfo:Object (BFO_0000030)
Causally unified material artefact composed of physically connected,
separable MaterialComponent parts. Satisfies
Assembly ⊑ MaterialArtifact ⊑ bfo:Object.
A shaft is a single causally unified mechanical component with subparts (bearings, seals, keys, sleeves, spacers as evidenced in the Known Component Terms). It has physically connected removable/maintainable subcomponents and forms a single functional unit. While 'ENGINE COMPONENT' appears in the parent candidates, this is too specific - shafts exist in many types of rotating machinery beyond engines (pumps, compressors, turbines). Assembly is the most appropriate BFO-grounded genus.
3
Necessary Parts
No necessary parts recorded (concept may be primitive at this level).
These components are universally necessary for shaft operation: keys for torque transmission, seals for leakage prevention, and sleeves for proper mounting of other components. Spacers and extensions are subtype-specific rather than universal requirements.
4
Process Participation Signature ⟨I, O, T⟩
Inputs (I)
—
Outputs (O)
—
Transformation (T)
rotational mechanical energy transmitted through the shaft from input to output with minimal energy loss
Shaft receives mechanical power input and transmits it to mounted components (impellers, gears, etc.). The transformation is pure mechanical power transmission through rotation - no change in energy type, just spatial/mechanical transmission from one location/component to another.
5
Axiom Mode Decision
Necessary conditions only
— modelled as a primitive universal
(⊑, SubClassOf). Identity is grounded in designed
function and cannot be reduced to a property checklist.
Constructive classification based on physical structure. Under OWA, sufficient conditions for shaft identity could lead to false positives - any assembly with a shaft key and rotational motion might be classified as a shaft rather than a more specific equipment type that contains a shaft. The structural differentia provides necessary conditions while allowing domain experts to validate sufficiency.
Cross-Standard Observations
Only one source definition available. The definition from ISO 15926-4 clearly establishes the shaft as an engine component, but the extensive subtype list shows shafts are used across many rotating equipment types beyond engines.
