1、Designation: D4296 83 (Reapproved 2015)1Standard Practice forSampling Pitch1This standard is issued under the fixed designation D4296; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parenthes
2、es indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTESI units formatting was corrected editorially in May 2015.1. Scope1.1 This practice covers procedures for sampling pitch atpoints of manufacture, storage, and de
3、livery.1.2 The values stated in SI units are to be regarded asstandard. The values in parentheses are for information only.1.3 This standard does not 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
4、-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific warningstatements are given in 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 ma
5、terial.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 material.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
6、 whole material.2.1.5 representative samplea part of a homogeneousmaterial, or a part of the composited and mixed portions of amaterial, which carries all the true properties and physicalcharacteristics of the whole material.2.1.6 samplea part taken as representative of a wholematerial.3. Summary of
7、 Practice3.1 Samples of liquid pitches are taken from process lines,storage, and shipment containers in increments required toprepare a representative sample for testing.3.2 Samples of solid pitches are taken from loadingsystems, storage, and shipment containers in increments re-quired to prepare a
8、representative sample for testing.4. Significance and Use4.1 Sampling is as important as testing. If the sampling isimproperly done, the sample of 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 takean
9、other sample; whereas, if the sample is properly taken andthe analysis is in error, another analysis can readily be made ofthe original sample.4.2 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
10、.2.2 To ascertain the maximum variation in characteristicswhich the material possesses.4.3 A good sampling plan has the following characteristics: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 mat
11、erial.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 cost of sampling, inspection oftesting, and administration.4.3.6 It provides information concerning the quality of theproduct.4.4 Sampling IntegrityWhen on
12、e takes a sample, one isattempting to represent a batch or lot of material with thatsample. Different forms of pitch, and pitch in different types ofcontainers, need to have different sampling plans and appro-priate sampling equipment. Each sampling plan should bedesigned so that it accomplishes its
13、 objective, which is toascertain the characteristics or quality of a batch or lot ofmaterial.5. Selection of Samples5.1 Pitches shall be sampled by the producer at the point ofmanufacture or storage, and at such time as to allow the tests1This practice is under the jurisdiction of ASTM Committee D02
14、 on PetroleumProducts, Liquid Fuels, and Lubricantsand is the direct responsibility of Subcom-mittee D02.05 on Properties of Fuels, Petroleum Coke and Carbon Material.Current edition approved April 1, 2015. Published May 2015. Originallyapproved in 1983. Last previous edition approved in 2009 as D42
15、96 83(2009).DOI: 10.1520/D4296-83R15E01.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1controlling acceptance or rejection of quality, as specified bythe consumer, to be made in advance of a shipment.5.2 Samples of pitches shall be t
16、aken by the consumer fromthe shipment containers immediately upon delivery and receiptand tests controlling acceptance or rejection of quality, asdescribed by the consumers specifications, shall be made assoon as possible.6. Size of Samples6.1 The sample size of liquid materials shall be as follows:
17、6.1.1 From process lines, 1 L (1 qt).6.1.2 From bulk storage, 1 L (1 qt) or 1 L aliquot of com-posite sample.6.1.3 From bulk shipment containers, 1 L (1 qt) or 1 Laliquot of composite sample.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 ma
18、terials 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 barrels or drums, 0.5 L (1 pt) or 0.5 L aliquot ofcomposite sample.7. Collection of Gross Sample7.1 A collection o
19、f 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 pitch sampled will be representedproportionately in the gross sample, and with such frequencythat a gross sample of t
20、he 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. When samples are collected from the surface of loadedshipments, the gross sample shall consist of nine increments ofa
21、pproximately 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 quantity.9. Protection and Preservation of Samples9.1 Sample containers shall be new or reusable containerswhich can
22、 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 liquid samplecontainers shall be positively covered, but not tightly sealed.Containers of solid materials shall be tight
23、ly 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 Immediately after filling and sealing, the samplingcontainers shall be properly marked for identification with asuita
24、ble 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 valves installed in the lines or up the side of thetanks. A typical tank valve is shown in Fig. 1, and suitable linevalv
25、es 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 pipe and unloading line.10.1.3 A weighted sample bottle similar to those shown inFig. 4 and Fig. 5, or a “thief sa
26、mpler” 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” sampler may be used to samplematerials in drums or barrels.10.2 Sampling Equipment for Solid Materials:10.2.1 Samples fr
27、om 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 trucks.10.2.3 A sampling spear as shown in Fig. 8 may be used tosample materials in drums, barrels, bags, and silos.10.
28、3 Sampling Containers:10.3.1 Containers for liquid materials shall be wide-mouthcans with line screw caps or triple-seal friction-top cans.FIG. 1 Typical Submerged Sampling DeviceD4296 83 (2015)1210.3.2 Containers for formed pitches or crushed solid pitchshall be triple-seal friction-top cans, seala
29、ble plastic or papercartons with inert inside coating, plastic sacks placed in othercontainers suitable for handling, or substantial strength paperbag which can be stapled closed.FIG. 2 In-Line Sampling DeviceFIG. 3 Pipeline SamplerD4296 83 (2015)1310.4 Mixing Equipment for Solid Materials:10.4.1 Se
30、ction of clean 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 tosmall
31、er sizes by mixing and quartering as shown in Fig. 10.10.5 Mixing Equipment for Liquid Materials:10.5.1 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 is recommended forsample volumes over 4 L (1 g
32、al) to 20 L (5 gal) in size.11. Hazards11.1 The sampler shall wear protective clothing, goggles,and rubber or heat-resistant gloves to protect oneself fromaccidental contact with hot liquid pitch.11.2 For prolonged exposure to the presence of pitch vaporsor pitch dust, a suitable respirator mask sho
33、uld 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 avoided when there isa possibility of shunting operations taking place. It is recom-mended that flags be placed on b
34、oth 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 asstorage tanks, tank cars, and tank trucks.12. Sampling Liquid Pitch12.1 The following three sampling methods are recom
35、-mended for sampling vertical tanks not capable of beingagitated:FIG. 4 Weighted Sampling CanD4296 83 (2015)1412.1.1 Sample-Valve MethodLocate valves, with easy andsafe access provided, on the side of the tank with the first in thetop third of the tank, but no higher than 1 m (3 ft) from the top;the
36、 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 product fromeach sample valve for test or composite.12.1.2 Thief Sampling
37、 MethodTake samples at the top,middle and lower sections of the tank by lowering a thiefsampler into the material. A satisfactory type with instructionsfor use is shown in Fig. 6. The samples may be testedseparately or combined and mixed thoroughly for a compositeanalysis.12.1.3 Weighted Sample Bott
38、le 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. 5.12.1.3.1 The essential feature of the method is to drop thestoppered bottle into the material to the desired dep
39、th, 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 possible,re-insert the stopper, lower into the material to the nextsampling depth.12.1.3.2 Normally, there is not e
40、nough 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 levels of the material, discardthe first of successive samples to rinse the bottle and thenreturn the bottle to the
41、 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, and a 1 L to 4 L (14 gal to 1 gal) aliquot ofthe composite taken for determining the average characteristicsof the material.12.2 Sampli
42、ng Bulk Storage Tanks Equipped with Mechani-cal Agitators or Recirculating PumpsWhen the tank isequipped with operating mechanical agitators or recirculatingNOTE 1This type sampler is lowered into the tank with the stopper in place. When the desired depth is reached, the stopper is removed by meanso
43、f the attached wire, cord, or chain and the container allowed to fill. Complete filling is indicated by the cessation of bubbles of air from the can at thesurface of the liquid. The sampler is then withdrawn from the tank and the contents poured into the clean sampler container. A clean can (bottle)
44、 mustbe used for each sample taken.FIG. 5 Throw-Away Container SamplerD4296 83 (2015)15pumping systems which are performing adequate 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 Tr
45、ucks:12.3.1 Samples of hot liquid materials may be taken by thedip method using a clean wide-mouth or friction-top can in asuitable 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 c
46、arefullyremove. Use a clean container to take each sample, and thentransfer the material sampled to another clean container forretention and testing.12.3.2 If incremental samples are required for subsequentcomposite, samples may be taken as described in 12.1.2 or12.1.3.12.3.3 When tank cars or tank
47、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 thedischarge side of the pump, or in a completely filled line inwhich gravity creates the materials flo
48、w.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 into a sample receiver. Before the sample istaken, draw 4 L (1 gal) of the material from the pipe val
49、ve anddiscard.12.3.3.2 Take samples of 1 L (1 qt) at such frequency duringthe loading or unloading to provide a 4 L to 8 L (1 gal to 2 gal)composite of the material. At the completion of the loading orunloading, thoroughly mix the collected sample and take a0.5Lto4L(18 gal 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 shi
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