Home>ASTM Standards>ASTM G9-07(R2020) pdf free download

ASTM G9-07(R2020) pdf free download

ASTM G9-07(R2020) pdf free download.Standard Test Method for Water Penetration into Pipeline Coatings
1. Scope
1.1 This method covers the determination of the apparent rate of depth of water penetration into insulating coatings applied to pipe. 1.2 The values stated in SI units are to be regarded as the 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 appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
5. Apparatus
5.1 Immersion Cell—Any suitable nonmetallic vessel to contain the test specimens. Dimensions of the vessel shall permit the following requirements: 5.1.1 Test specimens shall be suspended vertically with at least 25 mm (1.0 in.) clearance from the sides and bottom. 5.1.2 Test specimens shall be separated by not less than 25 to 40 mm (1 to 1.5 in.) and a vertically suspended anode shall be placed at an equal distance from each specimen not less than the separation of distance. 5.1.3 The test vessel shall be deep enough to allow for immersion of the samples in the electrolyte to the level specified in 8.1. N OTE 1—Commercially available, glass battery jars in 2-L (0.55-gal) and 10-L (2.7-gal) sizes can be conveniently used with 19-mm (0.75-in.) and 51-mm (2.0-in. nominal) diameter specimens, respectively. 5.1.4 A suitable sample support plate fabricated from a material having a low dielectric constant shall be used to suspend the samples and anode above the immersion cell. The support plate shall contain an access hole for the reference electrode. A typical test cell is illustrated in Fig. 1. 5.2 Electrolyte, consisting of tap water with the addition of 1 weight % ofeach ofthe following technical-grade anhydrous salts: sodium chloride, sodium sulfate, and sodium carbonate. N OTE 2—Add 10 g of each for each litre (0.26 gal) of water. 5.2.1 The electrolyte in the immersion cell shall be main- tained at the proper level by regular additions of tap water. The electrolyte shall not be reused after completion of the test. 5.3 Voltage Source—A direct current power supply, capable of supplying low ripple voltage shall be used to maintain a potential difference of 6.0 6 0.1 V dc between each of the test specimens and a common electrode. 5.4 Connectors—Wiring connections from the anode to the specimen shall be of No. 18 AWG insulated copper. Attach- ment to the anode shall be sealed and kept above the level of the electrolyte. Attachment to the specimen shall be made by a method that will allow disconnection from the anode when the measuring bridge is in use. A convenient means for accom- plishing this is through the use of insulated pin-type jacks. 5.5 Capacitance Bridge—Measurements of equivalent specimen capacitance and coating dissipation factor shall be made with a low-voltage a-c, resistive-ratio-arm type measur- ing bridge having the following characteristics: 5.5.1 Oscillator frequency, 1 kHz 6 2 %, 5.5.2 Series capacitance range, 1 to 1100 pF 6 1 %, 5.5.3 Series capacitance sensitivity, 0.5 pF, 5.5.4 Dissipation factor range, 0.001 to 1.0 at 1 kHz, and 5.5.5 Dissipation factor sensitivity, 0.001 at 1 kHz. 5.6 Measuring Circuit—Measurements of specimen capaci- tance and coating dissipation factor shall be made using a circuit that places the sample unknown in series with the comparison circuit of the measuring bridge. Connection of the unknown to the measuring bridge shall be made in such a manner as to eliminate the introduction of stray capacitance into the measuring circuit. A diagram for connecting the test cell to the bridge is shown in Fig. 2. In this arrangement, both the test leads are shielded and the chassis of the bridge is grounded. The immersion cell shall also be shielded to avoid capacitance effects from surrounding objects. N OTE 3—A shield for the test cell can conveniently be fabricated from most commercially-available tin or aluminum foils of approximately 0.0382-mm (0.0015-in.) thickness and formed around the container. 5.7 Thickness Gage—Measurements of coating thickness will be required for this test. Any instrument suitable for use with Test Method G12 can be used.

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