Standard Svensk standard · SS-EN ISO 6145-7:2019

Gasanalys - Framställning av kalibreringsgasblandningar med dynamisk volymetrisk metod - Del 7: Termiska massflödesregulatorer (ISO 6145-7:2018)

Status: Gällande

Köp denna standard

Standard Svensk standard · SS-EN ISO 6145-7:2019

Gasanalys - Framställning av kalibreringsgasblandningar med dynamisk volymetrisk metod - Del 7: Termiska massflödesregulatorer (ISO 6145-7:2018)
Prenumerera på standarden - Läs mer Dölj
Pris: 755 SEK
standard ikon pdf

PDF

Pris: 755 SEK
standard ikon

Papper

Pris: 1 208 SEK
standard ikon pdf + standard ikon

PDF + papper

Fler alternativ Färre alternativ
Omfattning
ISO 6145 is a series of documents dealing with various dynamic methods used for the preparation of calibration gas mixtures. This document specifies a method for continuous preparation of calibration gas mixtures, from nominally pure gases or gas mixtures by use of thermal mass-flow controllers. The method is applicable to preparation of mixtures of non-reacting species, i.e. those which do not react with any material of construction of the flow path in the thermal mass-flow controller or the ancillary equipment.
If this method is employed for preparation of calibration gas mixtures the optimum performance is as follows: the relative expanded measurement uncertainty U, obtained by multiplying the standard uncertainty by a coverage factor k = 2, is not greater than 2 %.
If pre-mixed gases are used instead of pure gases, mole fractions below 10-6 can be obtained. The measurement of mass flow is not absolute and the flow controller requires independent calibration.
The merits of the method are that a large quantity of the calibration gas mixture can be prepared on a continuous basis and that multi-component mixtures can be prepared as readily as binary mixtures if the appropriate number of thermal mass-flow controllers is utilized.
NOTE Gas blending systems, based upon thermal mass-flow controllers, and some including the facility of computerization and automatic control, are commercially available.

Ämnesområden

Kemisk analys (71.040.40)


Köp denna standard

Standard Svensk standard · SS-EN ISO 6145-7:2019

Gasanalys - Framställning av kalibreringsgasblandningar med dynamisk volymetrisk metod - Del 7: Termiska massflödesregulatorer (ISO 6145-7:2018)
Prenumerera på standarden - Läs mer Dölj
Pris: 755 SEK
standard ikon pdf

PDF

Pris: 755 SEK
standard ikon

Papper

Pris: 1 208 SEK
standard ikon pdf + standard ikon

PDF + papper

Fler alternativ Färre alternativ

Produktinformation

Språk: Engelska

Framtagen av: Gasanalys, SIS/TK 423/AG 02

Internationell titel: Gas analysis - Preparation of calibration gas mixtures using dynamic methods - Part 7: Thermal mass-flow controllers (ISO 6145-7:2018)

Artikelnummer: STD-80009257

Utgåva: 2

Fastställd: 2019-01-08

Antal sidor: 28

Ersätter: SS-EN ISO 6145-7:2011