1、Designation: D 4296 83 (Reapproved 2004)An American National StandardStandard Practice forSampling Pitch1This standard is issued under the fixed designation D 4296; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers procedures for sampling pitch atpoints of manufacture, storage, and delivery.1.2 This standard does no
3、t purport 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. Specific warningstatements are given in
4、 Section 11.2. Terminology2.1 Definitions:2.1.1 bulk samplea large sample, either from one place ormade up of several incremental samples of the same material.2.1.2 composite samplea thoroughly mixed gross sample.2.1.3 gross samplea large sample made up of severalportions (increments) of a mass of m
5、aterial.2.1.4 incrementa portion of a material to be combinedwith other portions of the same material to provide a largersample which will represent the whole material.2.1.5 representative samplea part of a homogeneous ma-terial, or a part of the composited and mixed portions of amaterial, which car
6、ries all the true properties and physicalcharacteristics of the whole material.2.1.6 samplea part taken as representative of a wholematerial.3. Summary of Practice3.1 Samples of liquid pitches are taken from process lines,storage, and shipment containers in increments required toprepare a representa
7、tive sample for testing.3.2 Samples of solid pitches are taken from loading sys-tems, storage, and shipment containers in increments requiredto prepare a representative sample for testing.4. Significance and Use4.1 Sampling is as important as testing. If the sampling isimproperly done, the sample of
8、 the material will be in error,and the analysis will not represent the true properties of thematerial, and it may be impossible or impracticable to takeanother sample; whereas, if the sample is properly taken andthe analysis is in error, another analysis can readily be made ofthe original sample.4.2
9、 Samples may be taken for either of the following twopurposes:4.2.1 To represent as nearly as possible an average of thebulk of the materials sampled, or4.2.2 To ascertain the maximum variation in characteristicswhich the material possesses.4.3 A good sampling plan has the following characteristics:
10、4.3.1 It protects the consumer against the acceptance of abad batch of material.4.3.2 It protects the producer against the rejection of a goodbatch of material.4.3.3 It gives long-range protection to the consumer.4.3.4 It encourages the producer to keep his process incontrol.4.3.5 It minimizes the c
11、ost of sampling, inspection oftesting, and administration.4.3.6 It provides information concerning the quality of theproduct.4.4 Sampling IntegrityWhen one takes a sample, one isattempting to represent a batch or lot of material with thatsample. Different forms of pitch, and pitch in different types
12、 ofcontainers, need to have different sampling plans and appro-priate sampling equipment. Each sampling plan should bedesigned so that it accomplishes its objective, which is toascertain the characteristics or quality of a batch or lot ofmaterial.5. Selection of Samples5.1 Pitches shall be sampled b
13、y the producer at the point ofmanufacture or storage, and at such time as to allow the testscontrolling acceptance or rejection of quality, as specified bythe consumer, to be made in advance of a shipment.1This practice is under the jurisdiction of ASTM Committee D02 on PetroleumProducts and Lubrica
14、nts and is the direct responsibility of Subcommittee D02.05 onProperties of Fuels, Petroleum Coke and Carbon Material.Current edition approved Nov. 1, 2004. Published November 2004. Originallyapproved in 1983. Last previous edition approved in 1999 as D 4296 83 (1999).1Copyright ASTM International,
15、100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2 Samples of pitches shall be taken by the consumer fromthe shipment containers immediately upon delivery and receiptand tests controlling acceptance or rejection of quality, asdescribed by the consumers specificat
16、ions, shall be made assoon as possible.6. Size of Samples6.1 The sample size of liquid materials shall be as follows:6.1.1 From process lines, 1 L (1 qt).6.1.2 From bulk storage, 1 L (1 qt) or 1-L aliquot ofcomposite sample.6.1.3 From bulk shipment containers, 1 L (1 qt) or 1-Laliquot of composite s
17、ample.6.1.4 From barrels or drums, 0.5 L (1 pt) or 0.5-L aliquot ofcomposite sample.6.2 The sample size of solid materials shall be as follows:6.2.1 From storage area, 4 L (1 gal) or 4-L aliquot ofcomposite sample.6.2.2 From bulk shipment containers, 4 L (1 gal) aliquot ofcomposite sample.6.2.3 From
18、 barrels or drums, 0.5-L (1 pt) or 0.5-L aliquot ofcomposite sample.7. Collection of Gross Sample7.1 A collection of gross sample represents a lot or batch ofmaterial and is composed of a number of increments.7.1.1 Collect the increments regularly and systematically, sothat the entire quantity of pi
19、tch sampled will be representedproportionately in the gross sample, and with such frequencythat a gross sample of the required amount will be collected.8. Size of Increments8.1 To collect samples, use a shovel or specially designedtool or mechanical means for taking equal portions or incre-ments. Wh
20、en samples are collected from the surface of loadedshipments, the gross sample shall consist of nine increments ofapproximately equal quantity. When sampling from piles,conveyer belts, and so forth, the gross sample shall consist ofnot less than 25 nor more than 50 increments of approximatelyequal q
21、uantity.9. Protection and Preservation of Samples9.1 Sample containers shall be new or reusable containerswhich can be thoroughly cleaned with a solvent and wiped drywith a clean dry cloth.9.2 Care shall be taken to prevent the sample from becom-ing contaminated. Immediately after filling, hot liqui
22、d samplecontainers shall be positively covered, but not tightly sealed.Containers of solid materials shall be tightly and positivelysealed.9.3 While sampling during inclement weather, attentionshall be paid to prevent water from dropping into the hot liquidsample or samples of solid materials.9.4 Im
23、mediately after filling and sealing, the samplingcontainers shall be properly marked for identification with asuitable pencil on the container itself, not on the lid.10. Apparatus10.1 Sampling Equipment for Liquid Materials:10.1.1 If so equipped, pipe lines and storage tanks may besampled from valve
24、s installed in the lines or up the side of thetanks. A typical tank valve is shown in Fig. 1, and suitable linevalves are illustrated in Fig. 2 and Fig. 3.10.1.2 For sampling tank trucks, a pipe connection withattached sample valve similar to the one shown in Fig. 2 maybe inserted between the outlet
25、 pipe and unloading line.10.1.3 A weighted sample bottle similar to those shown inFig. 4 and Fig. 5, or a “thief sampler” as shown in Fig. 6,ora“dip sampler” similar to that shown in Fig. 7, may be used tosample production and storage tanks, tank cars, and tanktrucks.10.1.4 A “tube” or “thief” sampl
26、er may be used to samplematerials in drums or barrels.10.2 Sampling Equipment for Solid Materials:10.2.1 Samples from loading systems may be taken with ashovel, metal or plastic scoop, or metal can.10.2.2 A shovel may be used to sample storage bins, pitchpiles, pitch bays, hopper cars, and dump truc
27、ks.10.2.3 A sampling spear as shown in Fig. 8 may be used tosample materials in drums, barrels, bags, and silos.10.3 Sampling Containers:10.3.1 Containers for liquid materials shall be wide-mouthcans with line screw caps or triple-seal friction-top cans.10.3.2 Containers for formed pitches or crushe
28、d solid pitchshall be triple-seal friction-top cans, sealable plastic or papercartons with inert inside coating, plastic sacks placed in othercontainers suitable for handling, or substantial strength paperbag which can be stapled closed.10.4 Mixing Equipment for Solid Materials:10.4.1 Section of cle
29、an canvas or plastic sheet of sufficientsize to contain a large bulk sample which is to be reduced bymixing and quartering.10.4.2 A “riffle” as shown in Fig. 9 may be used forreducing gross samples to smaller sizes for testing.10.4.3 A “shovel” may be used to reduce gross samples tosmaller sizes by
30、mixing and quartering as shown in Fig. 10.10.5 Mixing Equipment for Liquid Materials:FIG. 1 Typical Submerged Sampling DeviceD 4296 83 (2004)210.5.1 Sample sizes of 4 L (1 gal) or less can be mixed bythorough stirring with a metal rod or wide blade metal paddle.10.5.2 A heavy duty electric stirrer i
31、s recommended forsample volumes over 4 L (1 gal) to 20 L (5 gal) in size.FIG. 2 In-Line Sampling DeviceFIG. 3 Pipeline SamplerD 4296 83 (2004)311. Hazards11.1 The sampler shall wear protective clothing, goggles,and rubber or heat-resistant gloves to protect oneself fromaccidental contact with hot li
32、quid pitch.11.2 For prolonged exposure to the presence of pitch vaporsor pitch dust, a suitable respirator mask should be worn toavoid inhalation of pitch vapors or dust. It is recommended thatan appropriate barrier cream be applied to exposed areas of theskin.11.3 Sampling from rail cars shall be a
33、voided when there isa possibility of shunting operations taking place. It is recom-mended that flags be placed on both ends of the car to preventaccidental movement during sampling.11.4 It is recommended that no fewer than two persons bepresent when samples are taken from hot bulk vessels such assto
34、rage tanks, tank cars, and tank trucks.12. Sampling Liquid Pitch12.1 The following three sampling methods are recom-mended for sampling vertical tanks not capable of beingagitated:12.1.1 Sample-Valve MethodLocate valves, with easy andsafe access provided, on the side of the tank with the first in th
35、etop third of the tank, but no higher than 1 m (3 ft) from the top;the second in the middle of the tank; and the third in the bottomthird of the tank, but no lower than 1.1 m(312 ft) from thebottom. A recommended design of the sample valve is shownin Fig. 1. Draw a minimum of 4 L (1 gal) of the prod
36、uct fromeach sample valve for test or composite.12.1.2 Thief Sampling MethodTake samples at the top,middle and lower sections of the tank by lowering a thiefsampler into the material. A satisfactory type with instructionsFIG. 4 Weighted Sampling CanD 4296 83 (2004)4for use is shown in Fig. 6. The sa
37、mples may be testedseparately or combined and mixed thoroughly for a compositeanalysis.12.1.3 Weighted Sample Bottle MethodTake samples atthe top, middle, and lower sections of the tank by lowering thebottle into the material. Two types of weighted samplingbottles are illustrated in Fig. 4 and Fig.
38、5.12.1.3.1 The essential feature of the method is to drop thestoppered bottle into the material to the desired depth, and thenpull the stopper by means of an attached chain. When thematerial fills the bottle, lift out of the liquid and empty into aclean container. Drain the bottle as completely as p
39、ossible,re-insert the stopper, lower into the material to the nextsampling depth.12.1.3.2 Normally, there is not enough undrained residuefrom the first sample to affect the properties of the next sampletaken from a different level. However, if substantial materialdifference is suspected at various l
40、evels of the material, discardthe first of successive samples to rinse the bottle and thenreturn the bottle to the same level for another sample.12.1.3.3 The three samples may be tested separately forconsistency to detect stratification or they may be combined,thoroughly mixed, anda1to4-L(14 to 1-ga
41、l) aliquot of thecomposite taken for determining the average characteristics ofthe material.12.2 Sampling Bulk Storage Tanks Equipped with Mechani-cal Agitators or Recirculating PumpsWhen the tank isequipped with operating mechanical agitators or recirculatingpumping systems which are performing ade
42、quate mixing of thetank contents, take a single sample by any of the methodsdescribed in 12.1.1, 12.1.2,or12.1.3 to use for test purposes.12.3 Sampling Tank Cars and Tank Trucks:12.3.1 Samples of hot liquid materials may be taken by thedip method using a clean wide-mouth or friction-top can in asuit
43、able holder or firmly attached to a metal rod. One such dipapparatus is shown in Fig. 7. Quickly lower the dip sampleabout 0.3 m (1 ft) below the surface of the liquid and carefullyremove. Use a clean container to take each sample, and thentransfer the material sampled to another clean container for
44、retention and testing.NOTEThis type sampler is lowered into the tank with the stopper in place. When the desired depth is reached, the stopper is removed by means ofthe attached wire, cord, or chain and the container allowed to fill. Complete filling is indicated by the cessation of bubbles of air f
45、rom the can at the surfaceof the liquid. The sampler is then withdrawn from the tank and the contents poured into the clean sampler container. A clean can (bottle) must be usedfor each sample taken.FIG. 5 Throw-Away Container SamplerD 4296 83 (2004)512.3.2 If incremental samples are required for sub
46、sequentcomposite, samples may be taken as described in 12.1.2 or12.1.3.12.3.3 When tank cars or tank trucks are being loaded orunloaded, samples may conveniently be taken from the pipeline through which material is flowing by insertion of asampling pipe into the rising section of the pipe line on th
47、edischarge side of the pump, or in a completely filled line inwhich gravity creates the materials flow.12.3.3.1 A suitable in-line sampling pipe is shown in Fig. 2and Fig. 3. Turn the opening of the sampling pipe to face theflow of the liquid. Provide the pipe with a valve or plug cockand discharge
48、into a sample receiver. Before the sample istaken, draw 4 L (1 gal) of the material from the pipe valve anddiscard.12.3.3.2 Take samples of 1 L (1 qt) at such frequency duringthe loading or unloading to providea4to8-L(1to2-gal)composite of the material. At the completion of the loading orunloading,
49、thoroughly mix the collected sample and take a 0.5to 4-L (18 to 1-gal) portion for testing.12.4 Sampling from Drums or Barrels:12.4.1 High-softening point pitches poured into drums forstorage and shipment will solidify at ambient temperatures andsampling should be made in accordance with the procedure in12.5.12.4.2 Some soft pitches stored or shipped in drums orbarrels will be semi-solid at ambient temperatures, and willpermit the insertion of drum heaters. Drum “Band Heaters” arealso useful in heating materials in semisolid condition. Afterthorough heating, the
