ASTM D4178-82(2012)

Standard Practice for Calibrating Moisture Analyzers

SIGNIFICANCE AND USE
This practice is intended to provide a method to calibrate moisture analyzers used on-stream or in the laboratory.
SCOPE
1.1 This practice covers a calibration technique based on the preparation of standards of known water content. This technique is applicable to the production of standards between 20 and 2000 cm3/m3 water.
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 14-Apr-2012
• ICS: 71.040.10 - Chemical laboratories. Laboratory equipment
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.D0 - Hydrocarbons for Chemical and Special Uses

Relations

• Replaced By: ASTM D4178-82(2017) - Standard Practice for Calibrating Moisture Analyzers
• Effective Date: 01-Oct-2017

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D4178 − 82 (Reapproved 2012)
Standard Practice for
Calibrating Moisture Analyzers
This standard is issued under the fixed designation D4178; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Significance and Use
1.1 Thispracticecoversacalibrationtechniquebasedonthe 3.1 This practice is intended to provide a method to cali-
preparation of standards of known water content. This tech-
brate moisture analyzers used on-stream or in the laboratory.
nique is applicable to the production of standards between 20
3 3
and 2000 cm /m water.
4. Apparatus
1.2 The values stated in SI units are to be regarded as
4.1 IceBathPrimaryStandardMoistureApparatus—Fig.1
standard. The values given in parentheses are for information
illustrates a typical system.
only.
4.2 Wet Test Meter, 1-L divisions.
1.3 This standard does not purport to address all of the
4.3 Bubble Meter, graduated in cubic centimetres.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
4.4 Pressure Gauge—A Bourdon-type spring gauge of test
priate safety and health practices and determine the applica-
gauge quality, 100 to 250 mm in diameter, with a scale range
bility of regulatory limitations prior to use. from 0 to 400 kPa (0 to 60 psi), maximum intermediate
graduations of 1.5 kPa (0.25 psi).
2. Summary of Practice
4.5 Wet Mole Sieve 5A, 60/80 mesh (other mesh sizes may
2.1 The practice is based on the principle that ice has a
be used, except powder).
vapor pressure of 0.611 kPa at 0°C. Therefore, when a carrier
gas at a constant gauge pressure of 207 kPa (30 psig) is passed
5. Preparation of Apparatus
throughamolecularsievesaturatedwithwaterandheldat0°C,
5.1 Saturate mole sieve with water.
the total pressure is equal to 207 kPa plus 98 kPa (one
5.1.1 Coverinbeakerenoughmolesievetofillthewetmole
atmosphere) and the water concentration of the gas leaving the
6 sieve container. Add water to cover mole sieve. Let stand
molecular sieve is [0.611/(207+98)]×10 ppm or 2000 ppm
overnight.
volume water, regardless of flow.
5.1.2 Drain the excess water by pouring the mole sieve
2.1.1 Acarrier gas at a constant gauge pressure of 207 kPa
slurry into a filtering funnel and letting all the free water drain
is passed through a molecular sieve drier and then routed over
out.
amolecularsievesupportsaturatedwithwaterandequilibrated
at 0°C.
NOTE 1—The useful lifetime of the wet mole sieve is not known. It is
2.1.2 By blending different volumes of the wet carrier gas recommended that the procedure described in 5.1.1 and 5.1.2 be followed
prior to each calibration.
with dried carrier gas, gas standards of known water concen-
tration can be prepared.
6. Procedure
2.2 Themoistureanalyzertobecalibratedisthenconnected
6.1 Fill the ice bath bucket for the primary standard appa-
tothesourceofthegasstandardofknownwaterconcentration.
ratus one third full of water; then add ice to bring the level to
full.
1 6.2 Close the wet flow and the diluent flow needle values.
This practice is under the jurisdiction ofASTM Committee D02 on Petroleum
Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcom-
6.3 Turn on the carrier gas supply (nitrogen or air) and
mittee D02.D0 on Hydrocarbons for Chemical and Special Uses.
adjust the regulator to 207 kPa (30 psig).
Current edition approved April 15, 2012. Published May 2012. Originally
approved in 1982. Last previous edition approved in 2005 as D4178–82(2005).
6.4 Open the diluent flow needle valve to obtain a carrier
DOI: 10.1520/D4178-82R12.
gas flow of 1 L/min, as measured with a wet test meter.
For a more complete discussion of this procedure, see Mator, R. T., “ Trace
Moisture Analyzers and Their Calibration,” Proceedings of the 20th Annual ISA
6.5 Allow the apparatus to equilibrate for 1 h. This allows
Analysis Instrumentation Symposium, May 12-15, 1974, Pittsburgh, PA, “Session:
Sampling a
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