1、Designation: D 6715 01 (Reapproved 2007)Standard Practice forSampling and Preparation of Salt Preserved (Cured) Hidesand Skins for Chemical and Physical Tests1This standard is issued under the fixed designation D 6715; the number immediately following the designation indicates the year oforiginal ad
2、option or, in the case of revision, 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. Scope1.1 This practice covers the sampling and preparation ofsalt-preserved (c
3、ured) hides for physical and chemical tests.The hides or skins to be tested are grouped into lots. Each lotis randomly sampled in such a manner as to produce arepresentative sample of that lot. This lot sample may be usedto determine compliance of the lot with applicable specificationrequirements, a
4、nd on the basis of results, the lot may beaccepted or rejected in its entirety.1.2 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-priate safety and health practices and dete
5、rmine the applica-bility of regulatory limitations prior to use.2. Terminology2.1 Definitions:2.1.1 brine-curingpreserving by immersing flayed hidesinto concentrated/saturated salt (sodium chloride) solutionuntil sufficient salt has been absorbed by the hide, thus makingit temporarily resistant to b
6、acterial action (cured).2.1.2 curecommonly used industry reference to salt pres-ervation.2.1.3 cured hides (salted hides)commonly used industryterm for salt-preserved hides.2.1.4 laboratory termsany laboratory terms and defini-tions employed within this practice are commonly used innormal laboratory
7、 practice and require no special comment.2.1.5 lot (or batch)units of products from a single type,grade, class, size, and composition, manufactured under essen-tially the same conditions and time.2.1.5.1 DiscussionSalt-preserved hides in formed lotsshould be produced from:(1) Units of product of sim
8、ilar size and type,(2) Salt-preserved hides obtained from the same producer (function-ally equivalent),(3) A single product method, or(4) Sequential production batches.2.1.6 salt preservation (cure)is defined as the action ofapplying salt (typically sodium chloride) to flayed hides inorder to make t
9、hem temporarily resistant to degradation bybacterial (enzymatic) action. Typically, this is achieved byeither brine-curing or wet-salting (salt-packing).2.1.7 salt-preserved (cured) hidesare defined as hides thathave been processed into a condition that makes them tempo-rarily resistant to degradati
10、on by bacterial (enzymatic) action.This is achieved by the application of adequate salt (typicallysodium chloride) to the hide.2.1.8 unitan item of salt-preserved hide in the form inwhich it is purchased, such as a single hide, skin, or any partthereof.2.1.9 wet-salting (salt-pack)the action of appl
11、ying suffi-cient granular salt (sodium chloride) to flayed hides (normallyupon the flesh side) over sufficient time, in order to have thesalt absorbed by the hide, making it temporarily resistant tobacterial action (cured).3. Significance and Use3.1 The sampling procedures described in this practice
12、 havebeen designed to ensure random sampling of salt-preservedhides and skins for physical and chemical tests. Salt-preservedhides are natural products and as such are subject to extensivevariability. The physical and chemical properties vary consid-erably depending on location on that specific hide
13、, side, or skinfrom which the test sample is taken. Random sampling ofspecimens from a predefined location and orientation mini-mizes test bias and variability. This practice defines theseparameters.3.2 In general, tests carried out upon salt-preserved hidesrequire composite lot samples generated us
14、ing the preparationmethods described within this practice. Subsequent tests typi-cally require those composite samples to be in two forms:3.2.1 Expressed Hide Fluidwhere residual hide fluid ispressed from each de-haired and cleaned individual hidesample, then equal volumes of each extracted fluid ar
15、e blendedtogether to create the composite sample.1This practice is under the jurisdiction ofASTM Committee D31 on Leather andis the direct responsibility of Subcommittee D31.02 on Wet Blue.Current edition approved Sept. 1, 2007. Published September 2007. Originallyapproved in 2001. Last previous edi
16、tion approved in 2001 as D 6715-01.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.2 Hide Material Samplewhere equal quantities ofde-haired and cleaned hide material are blended together tocreate a representative composite sample
17、.4. Conditioning4.1 Since many tests performed upon salt preserved hidesinvolve the assessment of bacterial action, conditioning of thehide samples should be avoided. When possible, samplepreparation should be performed immediately followingcompletion of sampling.4.2 Chemical and physical tests of s
18、alt-preserved hides,unless otherwise specified in the applicable test method,specification, or procurement document, shall be performedunder laboratory standard atmospheric conditions, which is 506 4 % relative humidity at a temperature of 23 6 1C (73.4 62F). If testing conditions vary from this sta
19、ndard, the actualconditions shall be included in the report of all such tests.5. Sampling Procedure5.1 Prior to sampling, identify the product properly as a lotor batch.5.2 Select units from locations scattered throughout the lot,not from the same portion of the lot, such as a single carton,layer, a
20、nd so forth. Take units without regard to quality.5.2.1 The number of samples taken depends on the reliabil-ity of the test results, the deviation of the properties, and theerror of the testing procedure. The number of samples takenmay be at the discretion of the user and the related test methodand
21、should also be recorded on the test report. It is recom-mended that 12 samples be taken for every 50 000 ft2of hidesor skins. These 12 shall be considered a lot or batch.NOTE 1By reason of possible high moisture contents of salt-preserved hides, samples should be taken and immediately sealed inairti
22、ght (non-absorbent) plastic wrap or bags, followed by storage in a coolplace until used.5.3 The standard location for sampling salt-preserved hidesis the kidney area (designated as Test Area A in Fig. 1).Sampling in the belly or shoulder area is only applicable if thatis the end product being sold o
23、r purchased.5.3.1 Skins (Fig. 1)Cut the test piece to the size and shaperequired for the tests to be made, with one edge parallel to and1 in. (25.4 mm) from the backbone line, beginning 4 in. (101mm) from the root of the tail. Pieces shall be cut from only oneside of the backbone of each skin. The t
24、est area for skinscorresponds to area A for cattlehides.5.3.2 CattlehidesThe location and size of cutting shall beas follows:5.3.2.1 Hides, Sides, Crops, Backs, and Bends (Fig. 1)Cutthe test piece to the size and shape required for the test to bemade, with one edge parallel to and 2 in. (51 mm) from
25、 thebackbone line beginning 7 in. (178 mm) from the root of thetail. In most instances, test piece A may be cut 4 by 4 in. (101by 101 mm). Sample double bends, belting butts, and hides ononly one side of the backbone (see Test Area A).5.3.2.2 Bellies (Fig. 1)Cut the test piece, X, 3-in. (76-mm)wide
26、and 5-in. (127-mm) long with one long edge parallel toand 1 in. (25.4 mm) from the belly line, DF. Locate the middleof the piece midway between D and F.5.3.2.3 Double Shoulders (Fig. 1)Cut the test piece, Y,3by 5 in. (76 by 127 mm) with a long edge parallel to and 1 in.(25.4 mm) from the shoulder li
27、ne, BE. Locate the middle of thepiece midway between B and E.5.3.3 Cut each specimen for test with its long dimensionperpendicular to the backbone line unless otherwise specifiedin the corresponding test method.5.3.4 When several specimens are required from each piece,cut them in order of their corr
28、esponding method, beginning atthe edge nearest the tail.5.3.5 When cutting specimens for physical tests, areasselected shall be free from visible defects such as cuts,scratches, and other obvious flaws.FIG. 1 Location of Test AreaD 6715 01 (2007)26. Sample Preparation6.1 Time is crucial in the prepa
29、ration of salt-preserved hidesfor chemical testing. The following procedures should beexecuted with a minimum of hide exposure to both the air andmoisture- or salt-absorbent materials (including human skin).Ensuring this will prevent or minimize any significant moistureor salt loss from the samples.
30、6.2 During all stages of preparation, samples shall always becut on a non-porous, non-absorbing hard surface using a cleansharp cutting tool, preferably a new razor or scalpel blade.Avoid excess pressure on the sample that could force liquid(moisture) from the hide sample.6.3 De-hairing and Cleaning
31、:6.3.1 Without damaging the hide surfaces, carefully removeall the hair and manure from each hide sample using appro-priate equipment (clippers, scissors, razor, knife, and so forth).6.3.2 Remove any loose surface salt or residual undesiredmaterial (manure, dirt, and so forth) from each hide sample.
32、NOTE 2Typically the volume of liquid extracted (pressed) from eachindividual hide sample is small and usually requires wringing (squeezing)of almost all the original hide sample to obtain sufficient volume ofexpressed liquid. Therefore it is recommended that after the circular hideplug for the hide
33、material composite (see 6.5) is cut, then the remaininghide sample be used for liquid extraction.6.4 Expressed Liquid Sample:6.4.1 Manually (hand squeezing) or mechanically (vice,clamp, or press) wring each hide sample so that the resultantexpressed fluid is captured in an appropriate clean and dryr
34、eceptacle (glass or plastic Petri dish, beaker, and so forth). Itis advisable to extract at least 2 mL of fluid per sample.6.4.2 Using an appropriate measuring device (such as acalibrated dropping pipette), blend together equal portions ofeach hide sample fluid into an appropriate (airtight) contain
35、er.6.4.3 Carefully mix the composite by gentle agitation, thenseal the container and store it until the liquid is required foruse.6.4.4 Storage of the liquid sample should be avoided, ifpossible. However, where it may be necessary, storage shouldbe kept to an absolute minimum and under refrigeratedc
36、onditions so as to minimize or eliminate any bacterial action.Refrigerated storage should be for no more than 8 h.6.5 Hide Material Sample:6.5.1 Using appropriate equipment (scalpel, single-edgedrazor blade, cutting die, and so forth), cut a 1 in. (25.4 mm)diameter circular plug (disc) from each ori
37、ginal hide sample.6.5.2 Uniformly dice each plug into14 in. (6 mm) cubes.6.5.3 Place all the diced-up samples into a suitably sizedairtight glass or plastic container that has minimal airspaceonce all diced hide samples have been added.6.5.4 Repeat the dicing procedure for each of the individualhide
38、 sample plugs, until the composite sample is complete.6.5.5 Thoroughly mix the composite sample.6.5.6 Storage of the composite hide sample should beavoided, if possible. However, where it may be necessary,storage should be kept to an absolute minimum and underrefrigerated conditions so as to minimiz
39、e or eliminate anybacterial action. Refrigerated storage should be for no morethan 8 h.7. Keywords7.1 chemical tests; cured hides; lot; physical tests; prepara-tion; salt-preservation; salted hides; sampling; unitASTM International takes no position respecting the validity of any patent rights asser
40、ted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by
41、the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receiv
42、e careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM Intern
43、ational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 6715 01 (2007)3
