compressor
Enable an AI agent to recognise a compressor, assess whether it can safely deliver its required gas-compression duty, and determine which operating or maintenance actions are permitted.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
Researched by: Codex + Grok
Purpose and description
Enable an AI agent to recognise a compressor, assess whether it can safely deliver its required gas-compression duty, and determine which operating or maintenance actions are permitted.
A machine that raises the pressure of a gas by reducing its volume or by transferring momentum to it, typically to store, transport, or drive a process stream.
It can be Match a required gas-compression duty to the installed machine and its documented limits.; Compare pressure, flow, temperature and power observations with an applicable performance baseline.; Identify mechanism-specific abnormal behaviour and request targeted inspection or measurement.; Evaluate a proposed start, stop or capacity adjustment against prerequisites and control authority.; Determine whether protective conditions require holding operation or invoking an approved response.; Plan isolation and maintenance using documented pressure boundaries, stored-energy hazards and access requirements..
Distinguishing features
Its intended working medium at the compression inlet is gas or vapour; a machine intended primarily to pressurise liquid belongs to a pump model.
It actively raises gas or vapour pressure; a receiver stores pressurised gas without performing compression.
Its documented duty identifies compression service; distinguish it from a fan or blower using the applicable equipment classification and operating duty, without assuming a universal pressure-ratio threshold.
Its intended energy transfer is into the gas to raise pressure; an expander primarily extracts energy as gas pressure falls.
Scope
+ Compression mechanism, stages and physical machine boundary
+ Gas or vapour service and material compatibility
+ Pressure, flow, power and temperature behaviour within the applicable operating envelope
+ Condition of compression elements, bearings, seals and internal lubrication where applicable
+ Capacity controls, protective functions and prerequisites for operation or maintenance
- Plant-wide process objectives and production scheduling
- Distribution piping and downstream gas users
- Standalone receivers and pressure-vessel integrity programmes
- The complete refrigeration or heat-pump cycle
- Detailed models of separately managed motors, turbines and electrical supplies
Characteristics
- Compression mechanism
- Reciprocating, rotary screw, rotary vane, scroll, centrifugal, axial, other documented mechanism, unknown Determines which performance limits, failure modes and control methods are applicable.
- Machine and package boundary
- Included stages and auxiliaries; links to separately modelled driver, coolers, separators and receiver Prevents package capabilities or faults from being incorrectly attributed to the compressor itself.
- Working-fluid specification
- Gas or vapour identity, composition range, moisture and contaminant limits, with specification reference Establishes compatibility and the conditions under which performance and protective limits apply.
- Suction pressure
- Pa or bar absolute, with measurement location and time Defines inlet conditions and supports calculation of the actual compression duty.
- Discharge pressure
- Pa or bar absolute, with measurement location and time Shows delivered pressure and proximity to applicable pressure limits.
- Delivered flow
- kg/s or m³/s; volumetric values require actual or reference pressure, temperature and composition basis Allows capacity comparisons without confusing inlet, discharge and reference-volume measurements.
- Gas temperatures
- °C or K at identified suction, interstage and discharge locations Supports assessment of compression heating, cooling effectiveness and temperature limits.
- Input power
- kW, identifying shaft or electrical measurement boundary Supports load and performance assessment against comparable operating conditions.
- Speed and capacity setting
- rpm and mechanism-specific setting such as load fraction, guide-vane angle or unloader position Explains delivered capacity and constrains permissible adjustments.
- Operating mode
- Stopped, starting, loaded, unloaded, stopping, tripped, maintenance-isolated, unknown; applicability documented Distinguishes production readiness from merely being stationary or powered.
- Applicable operating envelope
- Versioned manufacturer or approved engineering limits and maps for the installed configuration and fluid Provides evidence for deciding whether an operating point or proposed action is acceptable.
- Condition evidence
- Timestamped vibration, leakage, lubricant, inspection and performance observations with locations and operating context Makes condition judgements traceable and separates observations from suspected causes.
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.compressor-artifact
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 18 findings · 28 questions.
Compression identity and service Establishes what performs compression, what fluid it handles and where the machine boundary lies.
A compressor cannot be assessed correctly from its name alone because mechanism, fluid and package boundary change the applicable evidence and constraints.
Mechanism and boundary
Identifies the compression principle and included equipment.
Installed compression configuration
Record the documented mechanism, stage arrangement and distinction between the compressor and its surrounding package.
- Which compression mechanism and stage arrangement are installed, and what nameplate, drawing or manual establishes this? provenance
- Which driver, cooler, separator, lubrication and control components belong inside this compressor's recorded boundary? boundary
Fluid and duty
Defines the intended compression service and admissible inlet medium.
Working fluid and inlet quality
Record intended gas or vapour service and documented restrictions on composition, contamination and liquid presence.
- What gas or vapour composition and inlet-condition range define the required compression duty? definition
- What evidence establishes allowable moisture, particles and liquid carryover for this particular compressor? provenance
Compression duty and performance Connects observed pressure, capacity and energy demand to a comparable compression duty.
Pressure or flow alone cannot establish whether a compressor is meeting duty or losing performance.
Measured operating point
Makes inlet, outlet and capacity observations mutually interpretable.
Pressure, flow and temperature basis
Record a time-aligned operating point with explicit pressure references, flow basis and sensor locations.
- What are the simultaneous suction and discharge absolute pressures and temperatures at identified measurement points? measurement
- What flow is delivered, and is it mass flow or volumetric flow stated at explicitly defined conditions? measurement
Performance comparison
Assesses delivered duty and energy demand against evidence applicable to the installed machine.
Applicable capacity and power baseline
Associate measured performance with a manufacturer curve, acceptance test or justified historical baseline.
- Which baseline applies to this fluid, speed, capacity setting and inlet condition, and what corrections does it require? provenance
- How do delivered flow and measured input power differ from that baseline after accounting for measurement uncertainty and the power boundary? measurement
Operating envelope and capacity control Defines allowable operating points and the means available to move between them.
Different compression mechanisms require different capacity controls and operating restrictions; a generic running state is insufficient.
Mechanism-specific limits
Selects the limits relevant to the installed compression mechanism.
Admissible compression region
Record applicable pressure, temperature, speed, load and stability limits without importing restrictions from an unrelated compressor type.
- Which approved limits constrain this machine, including surge or choke boundaries where applicable and mechanical loading limits where applicable? provenance
- Where does the current operating point lie relative to those limits, and what uncertainty affects the assessed margin? measurement
Capacity actuation
Identifies the installed methods and prerequisites for changing compression output.
Permitted capacity transitions
Record available speed, unloading, recycle or other capacity controls and their approved transition conditions.
- Which installed actuators change capacity, and how do their settings affect delivered flow and machine loading? definition
- What prerequisites, sequencing, rate limits and authority govern a proposed start, loading change, unloading or stop? action
Compression-element condition Connects physical condition evidence to the compressor's mechanism and operating context.
The same symptom can have different implications across compressor mechanisms, so diagnosis must retain location, load and evidential uncertainty.
Mechanical and sealing condition
Tracks deterioration of the parts that compress, support and contain the gas.
Mechanism-specific degradation evidence
Record observations concerning installed compression elements, bearings, valves and seals while keeping suspected causes distinct from confirmed defects.
- What vibration, noise, leakage, inspection or capacity-loss evidence exists, and at what location, speed and load was it observed? measurement
- Which inspection or diagnostic procedure can distinguish the suspected compression-element, bearing, valve or seal fault? action
Lubrication and heat removal
Assesses installed lubrication and cooling provisions that sustain compression.
Lubrication and cooling adequacy
Record the lubrication arrangement and cooling evidence, distinguishing compression-chamber oil exposure from separately lubricated components.
- Which parts require lubrication, can lubricant contact the process gas, and which documented lubricant and cooling requirements apply? definition
- What lubricant pressure, temperature, condition and cooling measurements demonstrate adequacy at the current duty? measurement
Containment, protection and intervention Records protection coverage and conditions for intervening on a machine containing pressurised gas.
Stopping rotation does not establish depressurisation, isolation or readiness for restart or maintenance.
Protective coverage
Identifies the protective functions and external safeguards on which compressor operation depends.
Compression-hazard safeguards
Record applicable alarms, trips, pressure protection, reverse-flow prevention and mechanism-specific protective controls, including dependencies outside the machine boundary.
- Which safeguards address the documented compressor hazards, and where are their settings, coverage and verification status established? provenance
- What approved response applies when a safeguard activates, is bypassed or is unavailable? action
Isolation and return to service
Establishes intervention boundaries and evidence required before maintenance or restart.
Verified pressure and drive isolation
Record how the compressor is isolated from its driver and connected pressure sources, how trapped gas is managed and how readiness is re-established.
- Which suction, discharge, interstage and auxiliary connections can retain or reintroduce pressure, and which drive sources can cause movement? boundary
- What approved procedure and verification evidence are required for depressurisation, fluid-specific gas handling, maintenance access and subsequent return to service? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Kinds and varieties
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- reciprocating (piston) compressor
- rotary screw compressor
- centrifugal (dynamic) compressor
- axial compressor
- scroll compressor
- rotary vane compressor
- liquid-ring compressor
- diaphragm (membrane) compressor
- Which of these kinds and varieties hold for the sense of compressor this model covers, and on what evidence? provenance
Identifiers and schemes
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Wikidata - Q23586 - Item 'gas compressor'; distinct from Q178048 (audio compressor) and from Q178361 (clothing garment).
- ISO 3857 vocabulary - compressor (machine that increases the pressure of a gas) - ISO 3857-1 general term; later parts distinguish pneumatic tools and machines.
- UNSPSC - 401515xx (compressors) - Commodity family under industrial pumping and compression equipment; exact leaf codes split by type (reciprocating, rotary, centrifugal).
- CPC / HS - HS 8414 (air or vacuum pumps, air or other gas compressors and fans) - Trade heading that also covers fans and vacuum pumps; compressor-specific subheadings sit under 8414.80 / 8414.40.
- Which of these identifiers and schemes hold for the sense of compressor this model covers, and on what evidence? provenance
Standards and regulation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- ISO 1217:2009 Displacement compressors - Acceptance tests (ISO)
- ISO 5389:2005 Turbocompressors - Performance test code (ISO)
- ISO 7183 Compressed-air dryers - Specifications and testing (ISO) - adjacent when treating a compressed-air plant
- ASME PTC 10 Performance Test Code on Compressors and Exhausters (ASME)
- API 617 Axial and Centrifugal Compressors and Expander-compressors (American Petroleum Institute)
- API 618 Reciprocating Compressors for Petroleum, Chemical, and Gas Industry Services (API)
- API 619 Rotary-Type Positive-Displacement Compressors for Petroleum, Petrochemical, and Natural Gas Industries (API)
- ASME BPV Code Section VIII (pressure vessels / receivers that store the compressed gas) (ASME)
- PED 2014/68/EU Pressure Equipment Directive, for vessels and piping in the EU compressed-air/gas plant (European Union)
- OSHA 29 CFR 1910.169 Air receivers (United States)
- Which of these standards and regulation hold for the sense of compressor this model covers, and on what evidence? provenance
Real-world use
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Factory compressed-air plants driving pneumatic tools, actuators, and blow-off, usually with a rotary-screw package, dryer, and receiver.
- Process gas compression in refineries, LNG, and chemical plants (API 617 centrifugal or API 618 reciprocating trains).
- Refrigeration and HVAC vapour-compression cycles (hermetic scroll or reciprocating compressors in the refrigerant circuit).
- Pipeline and underground-storage gas transmission (large centrifugal or reciprocating units at compressor stations).
- Vehicle air brakes, suspension, and tyre inflation (engine-driven or electric reciprocating/vane units).
- SCUBA and industrial breathing-air filling (oil-free or filtered high-pressure reciprocating stages).
- Turbochargers and aircraft gas-turbine compressors as rotating stages that raise inlet air pressure before combustion.
- Which of these real-world use hold for the sense of compressor this model covers, and on what evidence? provenance
Typical measurements
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- discharge (gauge) pressure - 7-10 bar(g) shop air; 20-40 bar high-pressure industrial; 200-300 bar breathing-air; process gas from near-atmospheric to >100 bar - bar or MPa (gauge or absolute, stated)
- inlet volume flow (FAD, free-air delivery) - 0.1-1 m³/min small workshop; 5-50 m³/min plant screw packages; hundreds of m³/min large centrifugals - m³/min or m³/s, referred to stated inlet conditions
- shaft / package power - 0.75-15 kW portable; 15-250 kW industrial screw; MW-class process and pipeline machines - kW
- specific energy (power per unit FAD) - about 5.5-13 kW per m³/min at 7-10 bar(g) for oil-injected screws, depending on control and unload - kW/(m³/min) or kWh/m³
- pressure ratio (discharge/inlet absolute) - 2-4 per centrifugal stage; 3-12 per reciprocating stage; overall plant ratios from ~2 to >200 - dimensionless
- rotational speed - 500-1800 min⁻¹ industrial reciprocating; 1500-3600 min⁻¹ screws; 5 000-50 000+ min⁻¹ centrifugals and turbochargers - min⁻¹ (rpm)
- discharge temperature - 80-200 °C typical after a stage before cooling; limited by oil, seals, and gas stability - °C
- sound pressure level at 1 m - 60-85 dB(A) packaged/enclosed; >90 dB(A) unenclosed industrial machines - dB(A)
- Which of these typical measurements hold for the sense of compressor this model covers, and on what evidence? provenance
Failure modes and hazards
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Overpressure of the discharge system or receiver if the pressure-relief valve or unload control fails.
- Oil-flooded screw or reciprocating units contaminating process or breathing air; oil-fire or explosion in the discharge if oil coke/ignites in hot high-pressure air.
- Liquid slugging in reciprocating and screw machines when condensate or process liquid enters the compression chamber, causing rod/valve or rotor damage.
- Surge (flow reversal) in centrifugal and axial compressors, with vibration, overheating, and possible impeller damage.
- Loss of cooling water or aftercooler fouling, raising discharge temperature and degrading oil and seals.
- Receiver or piping rupture; stored compressed-gas energy is a blast/fragmentation hazard.
- Noise-induced hearing loss and vibration injury at unenclosed machines.
- Asphyxiation or toxic exposure if a process-gas compressor leaks into a confined space; oxygen enrichment fire risk from oxygen compressors.
- Stall and rotating stall in axial compressors (aero engines), leading to thrust loss or mechanical damage.
- Which of these failure modes and hazards hold for the sense of compressor this model covers, and on what evidence? provenance
Regional variation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- North America commonly quotes pressure in psig and flow in scfm; ISO/metric practice uses bar(g) or kPa and m³/min FAD referred to ISO 1217 inlet conditions.
- EU plants fall under PED for receivers and often ISO 8573 air-quality classes; US general industry uses OSHA air-receiver rules and ASME Section VIII stamping.
- API 617/618/619 dominate oil-and-gas procurement worldwide; general manufacturing more often buys ISO 1217-rated packaged screws.
- UK/Ireland 'compressor' in everyday speech often means the workshop air compressor; the same word in broadcast/audio means a dynamics processor (different thing).
- China GB and EU Ecodesign / energy-label rules set minimum package efficiencies for standard air compressors that the US does not match one-for-one.
- Which of these regional variation hold for the sense of compressor this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- fan / blower - A fan or blower moves gas against a small pressure rise (typically well below 1 bar); a compressor is specified when the discharge pressure or pressure ratio is high enough that density change and gas work dominate. ISO and trade practice put fans in the same HS heading but treat them as a different machine class.
- vacuum pump - A vacuum pump reduces pressure below atmosphere on the inlet side; a compressor raises pressure above the inlet, usually discharging above atmosphere. The same positive-displacement geometry can be either, distinguished by duty and porting, not by the rotor shape alone.
- pump (liquid) - A pump is built for incompressible liquid; a compressor is built for gas. Cavitation vs. surge, and the presence of a significant density change, separate the duties.
- turbocharger / supercharger - These are compressors applied to an engine intake. The neighbour is the application name; the test is whether the machine is an engine-boosting stage (driven by exhaust turbine or mechanically) versus a standalone process or plant compressor.
- audio dynamic-range compressor - An electronic or software signal processor that reduces dynamic range. Not a gas machine; Wikidata Q178048 versus Q23586. If it has no gas path, it is not this object.
- pressure regulator / reducer - A regulator drops pressure from a stored high-pressure source without adding shaft work; a compressor adds work to raise pressure.
- expander / turbine - An expander extracts work while gas pressure falls; a compressor consumes work while pressure rises. Same family of turbomachines, opposite energy sign.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of compressor this model covers, and on what evidence? provenance
Sources
- ISO 3857-1:1977 Compressors, pneumatic tools and machines - Vocabulary - Part 1: General - Establishes the general vocabulary that treats a compressor as a machine for raising gas pressure.
- ISO 1217:2009 Displacement compressors - Acceptance tests - Defines how displacement compressors are typed and performance-tested (volume flow, power, specific energy).
- ISO 5389:2005 Turbocompressors - Performance test code - Performance-test code for dynamic (turbo) compressors, separating them from positive-displacement machines.
- ASME PTC 10-2022 Performance Test Code on Compressors and Exhausters - North American performance-test practice for centrifugal and axial compressors.
- gas compressor (Q23586) - Canonical identifier and aliases for the mechanical gas compressor as a class of machine.
What the second pass must settle
- Does the registry intend this entry to cover every gas and vapour compressor mechanism, including refrigeration and vacuum-service applications, or are some assigned to neighbouring entries?
- Which classification authority should govern ambiguous compressor, blower and fan boundaries in this catalogue?
- Should packaged coolers, separators, lubrication equipment and controls be owned here or linked as independent registered things?
- Which manufacturer documents and applicable engineering requirements will establish mechanism-specific operating limits and permissible actions for each instance?
- What minimum instrumentation and evidence quality are required to distinguish degraded performance from changed inlet conditions, control settings or measurement error?