1、Designation: D 1838 07An American National StandardStandard Test Method forCopper Strip Corrosion by Liquefied Petroleum (LP) Gases1This standard is issued under the fixed designation D 1838; the number immediately following the designation indicates the year oforiginal adoption or, in the case of r
2、evision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the detection of the presence ofcomponents in liquefied petroleum gases
3、 which may be corro-sive to copper.NOTE 1For an equivalent copper strip test applicable to less volatilepetroleum products, see Test Method D 130.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not pu
4、rport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specificwarning statements, see 6.1, 9.
5、3.1, and Annex A1.2. Referenced Documents2.1 ASTM Standards:2D 130 Test Method for Corrosiveness to Copper fromPetroleum Products by Copper Strip TestE1 Specification for ASTM Liquid-in-Glass ThermometersD 1265 Practice for Sampling Liquefied Petroleum (LP)Gases, Manual MethodD 3700 Practice for Obt
6、aining LPG Samples Using a Float-ing Piston Cylinder2.2 ASTM Adjuncts:ADJD0130, ASTM Copper Strip Corrosion Standard forPetroleum33. Summary of Test Method3.1 A polished copper strip is immersed in approximately100 mL of the sample and exposed at a temperature of 37.8C(100F) for1hinacylinder of suit
7、able working pressure. Atthe end of this period, the copper strip is removed and rated asone of the four classifications of the ASTM Copper CorrosionStandards.4. Significance and Use4.1 Copper corrosion limits provide assurance that difficul-ties will not be experienced in deterioration of the coppe
8、r andcopper-alloy fittings and connections that are commonly usedin many types of utilization, storage, and transportation equip-ment.5. Apparatus5.1 Corrosion Test Cylinder, constructed of stainless steelwith an O-ring removable top closure according to the dimen-sions given in Fig. 1. Provide a fl
9、exible inert hose, such as onecomposed of aluminum or stainless steel, which permitsinverting the test cylinder as required in the procedure (seeNote 2). The whole assembly, including the corrosion testcylinder, shall be constructed to withstand a minimum hydro-static test pressure of 6900 kPa (1000
10、 psig). No leak shall bediscernible when tested at 3450 kPa (500 psig) with gas.NOTE 2Swivel connections with an adapter to fit a 6.4 mm (14 in.)pipe may be used.5.1.1 The assembly shall be tested for compliance with theminimum pressure rating of 6900 kPa (1000 psig) by hydro-static testing, or alte
11、rnative testing protocol acceptable to thelocal authority having jurisdiction, prior to first use. Additionaltesting can be required by the local authority having jurisdic-tion.5.1.2 The assembly shall be verified for gas tightness byleak testing at 3450 kPa (500 psig) with inert gas prior to firstu
12、se, whenever pressure-containing components of the assem-bly are replaced, or otherwise on an annual basis.5.1.3 Note the presence and length (about 60 mm) of theoutage tube shown in Fig. 1, to provide adequate ullage forsafety. A safety pressure relief device may also be incorporatedinto the design
13、 of the corrosion test cylinder, if desired. If apressure relief device is incorporated, ensure that the materialsof its construction will not affect the test results.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibilit
14、y of SubcommitteeD02.H0 on Liquefied Petroleum Gas.Current edition approved Nov. 1, 2007. Published November 2007. Originallyapproved in 1961. Last previous edition approved in 2006 as D 183806.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at s
15、erviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from ASTM International Headquarters. Order Adjunct No.ADJD0130.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM Internatio
16、nal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2 Water Bath, capable of being maintained at 37.8 60.5C (100 6 1F). Incorporate suitable supports to hold thetest cylinder in an upright position. Make the bath deep enoughso that the entire cylinder and valve
17、s will be covered during thetest.5.3 Temperature Sensing Device (TSD)Capable of moni-toring the desired test temperature in the bath to within anaccuracy of 60.5C (1F) or better. TheASTM 12C (12F) totalimmersion thermometer has been found suitable to use in thetest (see Specification E1). If used, n
18、o more than 25 mm (1 in.)of the mercury should extend above the surface of the bath atthe test temperature.5.4 Strip Polishing Vise, to hold the copper strip firmlywithout marring the edges. For convenient vises see TestMethod D 130.6. Materials6.1 Wash SolventUse acetone or knock test grade2.2.4 tr
19、imethylpentane. (WarningExtremely flammable.See Annex A1.)6.2 Copper Strip, approximately 12.5 mm (12 in.) wide, 1.5to 3.0 mm (116 to18 in.) thick, cut approximately 75 mm(3 in.) long from smooth-surfaced, hard-temper, cold-finishedcopper of 99.9 + % purity; electrical bus bar stock is generallysuit
20、able. Drill a 3.2 mm (18 in.) hole approximately 3.2 mm(18 in.) from one end in the center of the strip. The strips maybe used repeatedly but should be discarded if surfaces becomedeformed.6.3 Surface Preparation/Polishing Materials00 grade orfiner steel wool; silicon carbide grit paper or cloth of
21、varyingdegrees of fineness including 65-m (240-grit) grade; also asupply of 105-m (150-mesh) size silicon carbide grain orpowder and absorbent cotton. A commercial grade is suitable,but pharmaceutical grade cotton wool is most commonlyavailable and is acceptable.6.4 Copper Corrosion Standard Plaques
22、 are available.3Their care and inspection for stability are described in detail inTest Method D 130.7. Preparation of Strips7.1 Surface PreparationRemove all surface blemishesfrom all six sides of the strip obtained from a previous analysis.One way to accomplish this is to use 00 grade or finer stee
23、lwool or silicon carbide paper or cloth of such degrees offineness as are needed to accomplish the desired resultsefficiently. Finish with 65-m (240-grit) silicon carbide paperor cloth, removing all marks that may have been made by othergrades of paper used previously. Ensure the prepared copperstri
24、p is protected from oxidation prior to final preparation, suchas by immersing the strip in wash solvent from which it can bewithdrawn immediately for finish preparation (polishing) or inwhich it can be stored for future use.7.1.1 As a practical manual procedure for surface prepara-tion, a sheet of s
25、ilicon carbide paper may be placed on a flatsurface and then moisten the paper with wash solvent beforerubbing the strip against the silicon carbide paper or cloth witha circular motion. Protect the strip from contact with thefingers, such as by using ashless filter paper. Alternatively, thesurface
26、of the strip can be prepared by use of motor-drivenmachines using appropriate grades of dry paper or cloth.7.2 Final PreparationFor strips prepared in 7.1 or newstrips being used for the first time, remove a strip from itsprotected location, such as by removing it from the washsolvent. Polish first
27、the ends and then the sides with the105m (150m mesh) silicon carbide grains picked up witha pad of absorbent cotton moistened with wash solvent, makingsure that the surface is protected from coming in contact withthe fingers, such as by using ashless filter paper. Wipevigorously with fresh pads of a
28、bsorbent cotton and subse-quently handle without touching the surface of the strip withthe fingers. Padded forceps (to prevent the scratching of thesurface) have been found suitable to use. Secure the copperstrip in a vise or suitable holder and polish the main surfaceswith silicon-carbide grains on
29、 absorbent cotton. Do not polishin a circular motion. Rub in the direction of the long axis of thestrip, carrying the stroke beyond the end of the strip beforereversing the direction. Clean all metal dust from the strip byrubbing vigorously with clean pads of absorbent cotton until afresh pad remain
30、s unsoiled. When the strip is clean, withminimal delay, attach to the dip tube and lower into theprepared corrosion test cylinder (see Fig. 1).7.2.1 It is important to polish the whole surface of the stripuniformly to obtain a uniformly stained strip. If the edges showwear (surface elliptical) they
31、will likely show more corrosionthan the center. The use of a vise will facilitate uniformpolishing.Metric Equivalentsin. mm in. mm18 3.2 3 7614 6.4 6 152112 38.1FIG. 1 Copper Strip Corrosion Test CylinderD18380727.2.2 It is important to follow the order of preparation withthe correctly sized silicon
32、 carbide material as described in 7.1and 7.2. The final preparation is with 105-m silicon carbidegrain. This is a larger grain size than the 65-m paper used inthe surface preparation stage. The reason for this use of largersilicon carbide grains in the final preparation is to produceasperities (cont
33、rolled roughness) on the surface of the copper,which acts as sites for the initiation of corrosion reactions.8. Sampling8.1 Obtain a sample from a point in the LPG system thatwill give a representative sample of the volume being tested,such as from a dynamic flowing stream or from a well mixedcontai
34、ner, as appropriate. Preferably, collect the sample di-rectly into the corrosion test cylinder (5.1) after it has beenprepared for testing (9.1). Pay particular attention to safety andwarning notes in Practices D 1265 and D 3700.8.2 Alternatively, collect a sample in accordance with Prac-tices D 126
35、5 and D 3700.8.2.1 If a sample is first collected in a sampling cylinder,ensure that the interior surfaces are inert and will not react withcorrosive species. Sampling cylinders with protective (inert)internal coatings or surface treatments (such as fused glass)may be used.NOTE 3Some internal coatin
36、gs are porous and can adsorb or releasecontaminants that can affect test results.Also, fresh steel surfaces can reactwith some corrosive sulfur species and potentially remove them, whichcould result in a “false pass” in the copper strip corrosion test.8.3 The time between when the sample is collecte
37、d andwhen the test is begun should be held to a minimum (preferablyonly a few minutes) (see Note 4).8.4 In case of dispute, a sample shall be collected directlyinto a corrosion test cylinder.9. Procedure9.1 With Valve B (Fig. 1), open, place approximately 1 mLof distilled water into a clean test cyl
38、inder and swirl to moistenthe walls; allow the remainder to drain from the cylinder, insertthe freshly polished copper strip suspended from the hook onthe dip tube making sure that the bottom of the strip is at least6.4 mm (14 in.) from the bottom of the cylinder whenassembled.After assembly of the
39、apparatus, close both Valve A(Fig. 1), on closure assembly with outage tube, and Valve B.9.2 Holding the test cylinder upright so as not to wet thecopper strip with water, attach the sample source to the testcylinder Valve A (Fig. 1) by means of a short length of flexibleinert hose that has been pur
40、ged with the sample. Admit somesample to the cylinder by opening the valve at the samplesource and then Valve A.9.3 Close Valve A without disconnecting the test cylinderfrom the sample source. Invert the test cylinder and open ValveB to purge the air from the test cylinder. Return the test cylindert
41、o the upright position and drain any residual liquid through theopen Valve B. Close Valve B with the test cylinder now in itsupright position, open Valve A and fill the test cylinder with thesample. When the test cylinder is full, close Valve A, the valveat the sample source, and disconnect the tubi
42、ng.9.3.1 (WarningSafe means for the disposal of vapors andliquids during this and subsequent procedures must be pro-vided.)9.4 As soon as the flexible inert hose is disconnected, andwith the cylinder in its upright position, open Valve A slightlyso that all liquid above the end of the outage tube wi
43、ll beremoved from the test cylinder. When vapor first emerges fromValve A, close Valve A.9.5 With minimal delay, and as soon as practical after fillingand venting (described in 9.4) the test cylinder (see Note 4),immerse the test cylinder in the water bath maintained at 37.86 0.5C (100 6 1F). Allow
44、the test cylinder to remain in thebath for 1 h 6 5 min.NOTE 4Any delay between preparing the test cylinder, collecting thesample, and immersing the test cylinder in the water bath gives the copperstrip more time in the sample, and thus more time to potentially developincreased discoloration if corro
45、sive species are present in the sample.9.6 At the end of the test period remove the cylinder fromthe bath and, holding the cylinder in a vertical position, openthe bottom valve to a suitable disposal unit (9.3.1) until all ofthe liquid and most of the vapor is discharged.9.7 When only a slight press
46、ure remains in the cylinder,disassemble immediately and compare at once the copper stripthat has been exposed to the liquefied petroleum gases with theASTM Copper Strip Corrosion Standards.9.8 Handling only with stainless steel forceps, compare theexposed strip with the ASTM Copper Strip Corrosion S
47、tan-dards. Hold both the test strip and the standard in such amanner that light reflected from them at an angle of approxi-mately 45 will be observed. In handling the test strip duringthe inspection and comparison, the danger of marking orstaining can be avoided if it is inserted in a flat test tube
48、 whichis then stoppered with absorbent cotton.9.9 The added distilled water frequently causes isolatedbrown spots on the copper strip. The presence of these spotsshould be disregarded or the test should be repeated.9.10 If the copper strip shows any appreciable discoloration,the interior of the cyli
49、nder should be polished with steel wooland washed with wash solvent soon after use so as to be cleanfor another test.10. Report10.1 Report the results in accordance with one of theclassifications listed in Table 1. State the duration of the testand the test temperature.11. Precision and Bias11.1 In the case of ordinal classification data, no generallyaccepted method for determining precision or bias is currentlyavailable.12. Keywords12.1 copper corrosion; copper strip; liquefied petroleumgasesD1838073ANNEX(Mandatory Information)A1. WARNING STATEM
