ISO/TC 118/SC 6 - Air compressors and compressed air systems

This document specifies the performance test method of electrically driven low-pressure air compressor packages, where the compression is performed by positive displacement or dynamic compression; utilising atmospheric air as the compression gas. Low-pressure air compressor packages are often referred to as “blowers”. NOTE Throughout this document, the term ‘low-pressure compressor’ is used to describe a low-pressure air compressor (“blower”) package Low-pressure compressors with and without means of controlling flow (control may be electrical (e.g. with a variable frequency drive) or mechanical or both) are covered. This document applies to low-pressure compressors meeting all the following limits: — Atmospheric inlet air pressure between 0,5 bar and 1,1 bar. — Discharge vs inlet pressure differential between 0,1 bar and 2,5 bar. — Discharge vs inlet pressure ratio between 1,1 and 3,5. This document is not applicable to: — positive displacement low-pressure compressors with a liquid in the compression element (such as liquid ring pumps and liquid injected low-pressure compressor of screw type) — multi-stage low-pressure compressors other than multistage centrifugal compressors comprised of multiple, identical or very similar uncooled sections along a single shaft (repeating stages). — single shaft, multistage centrifugal compressors are treated from the point of measurement and calculation as a single stage

This document applies to electrically driven positive displacement and dynamic compressors. This document defines and describes the test method to evaluate the cycle energy requirement.

ISO 18740:2016 applies to any fixed (constant) speed, liquid cooled, packaged centrifugal air compressor which incorporates a centrifugal compression element of any type driven by an electric motor. It defines and describes acceptance tests for electrically driven packaged air compressors of standard types which are constructed to specifications determined by the manufacturer and which are sold against performance data published in the manufacturer's sales documentation. NOTE Items supplied shipped loose for installation at site are not considered to be a part of the compressor package. Such compressors are designed to draw in atmospheric air from their immediate surroundings and the performance data offered by the manufacturer usually relates to a normal ambient air inlet pressure.

ISO 11011:2013 sets requirements for conducting and reporting the results of a compressed air system assessment that considers the entire system, from energy inputs to the work performed as the result of these inputs. ISO 11011:2013 considers compressed air systems as three functional subsystems: supply which includes the conversion of primary energy resource to compressed air energy; transmission which includes movement of compressed air energy from where it is generated to where it is used; demand which includes the total of all compressed air consumers, including productive end-use applications and various forms of compressed air waste. ISO 11011:2013 sets requirements for analysing the data from the assessment, reporting and documentation of assessment findings, and identification of an estimate of energy saving resulting from the assessment process. ISO 11011:2013 identifies the roles and responsibilities of those involved in the assessment activity.

ISO/TR 12942:2012 gives a classification of modern compressor types and their definitions. ISO/TR 12942:2012 presents terms for use in technical and contractual specifications, manufacturer's literature, information searches and data processing systems, patent information, educational publications for students, service and maintenance instructions, industrial statistics and market surveys, as well as in design, quality, safety, testing and other standards, norms, regulations and codes.

ISO 1217:2009 specifies methods for acceptance tests regarding volume rate of flow and power requirements of displacement compressors. It also specifies methods for testing liquid-ring type compressors and the operating and testing conditions which apply when a full performance test is specified.

ISO 2151:2004 specifies methods for the measurement, determination and declaration of the noise emission from portable and stationary compressors and vacuum pumps. It prescribes the mounting, loading and working conditions under which measurements are to be made, and includes measurement or determination of the noise emission expressed as the sound power level under specified load conditions and the emission sound pressure level at the work station under specified load conditions. It is applicable to compressors for various types of gases, oil-lubricated air compressors, oil-flooded air compressors, water injected air compressors, oil-free air compressors, compressors for handling hazardous gases (gas compressors), compressors for handling oxygen, compressors for handling acetylene, high pressure compressors (over 40 bar/4 MPa), compressors for application at low inlet temperatures (i.e. below 0 °C), large compressors (over 1 000 kW input power), portable and skid-mounted air compressors, and rotary positive displacement blowers and centrifugal blowers and exhausters in applications of 2 bar/0,2 MPa or less. It is not applicable to compressors for gases other than acetylene having a maximum allowable working pressure of less than 0,5 bar/0,05 MPa, refrigerant compressors used in refrigerating systems or heat pumps, nor to hand-held portable compressors.

Establishes provisions for the safe design, construction, installation and operation of stationary and skid-mounted compressors. Specifies requirements to help minimizing compressor accidents and defines general safety practices for the field. It does not apply to prime movers. The following types of compressor are excluded: with a shaft input less than 2 kW; with an effective discharge pressure less than 0,5 bar or exceeding 50 bar; supplying air for breathing, diving or surgery, such used for air brake systems; ejektors.

Lays down a series of preferred pressures to be used as reference pressure when presenting performance data for pneumatic equipment. Components for compressed air systems should also be designet to meet the standardized pressures. The stated pressure are effective (gauge) pressures, given in bars.

Establishes basic concepts in English and French as well as symbols and units. Table 1 tabulates symbols and units referred to ISO/R 31 and ISO 3857; table 2 contains letters used as symbols; table 3 comprises letters and figures used as subscripts. An annex gives references.

Establishes terms and definitions in English and French relating to compressors, comprises: general, temperatures, flow rates, pressures, powers, specific energy requirement, efficiencies and related information.

Gives a classification of various types of compressors and some definitions. a list of equivalent English and French terms relating to some of the types is given in an annex, together with explanatory diagramms. Applies to compressors defined as machines for the displacement and compression of gaseous media for any pressure values, with the exeption of fans and vacuum pumps.

Specifies a method of determining the airborne sound and gives precise instructions for conducting the tests and reporting the results. An annex contains a format with tables for test report. Three figures illustrate the description.