1、Designation: F 1888 09An American National StandardStandard Test Method forCompression-Displacement of Baseballs and Softballs1This standard is issued under the fixed designation F 1888; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisi
2、on, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method describes a comparative measurementmethod for baseballs and softballs as defined by a
3、 staticcompression displacement test.1.2 This test method is based on a slow rate force-displacement measurement.1.3 This procedure is for baseballs and softballs meetingstandards established by the sports governing bodies.NOTE 1Since the compression-displacement of baseballs and soft-balls can infl
4、uence the performance characteristics, this test provides asimple method to compare and categorize such balls based on force levelsin a standardized compression-displacement test.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematical
5、conversions to SI units that are provided for information onlyand are not considered standard.1.5 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 pra
6、ctices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E 177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Term
7、inology3.1 Definitions of Terms Specific to This Standard:3.1.1 baseballs and softballs, nany such ball defined bythe rules of the game as published by the sports governingbodies.3.1.2 compression-displacement, nthe reduction in balldiameter under a specified compressive load between two flatplates.
8、 Synonymous with compression-deflection.3.1.3 force, nthe resistance to displacement. The interac-tion between test machine and ball during compression.3.1.4 four seams, nplane passing through the middle ofthe ball intersecting four stitch lines.3.1.5 two seams, nplane passing through the middle of
9、theball intersecting two stitch lines.4. Summary of Test Method4.1 The baseball or softball is placed between two flat-platesurfaces of a compression machine and then compressed to astandard displacement of 6.35-mm (0.25-in.). The compressionload (force) applied at the standard displacement is recor
10、ded.5. Significance and Use5.1 The static compression-displacement of a baseball orsoftball is a mechanical property which can correlate todynamic properties.5.2 This test method is suitable for obtaining data inresearch and development, quality control, and classifyingballs by the compression-displ
11、acement.5.3 Sports associations can use compression-displacementstandards in specifications for official baseballs and softballsstandards in specifications for official baseballs and softballsfor purposes of consistency of performance.5.4 This same test procedure can be utilized with othercompressiv
12、e forces and the specified force is not necessarilythe same as experienced in actual use.6. Apparatus6.1 Compression Device, to compress the test ball betweentwo flat plates to 0.25 in. (6.35 mm) displacement. Compres-sive force to 800 lb (3560 N) is sufficient.Ameans of centeringthe test ball so th
13、at the vertical axis of the ball aligns with thevertical axis of the compression device piston.1This test method is under the jurisdiction of ASTM Committee F08 on SportsEquipment and Facilities and is the direct responsibility of Subcommittee F08.26 onBaseball and Softball Equipment.Current edition
14、 approved June 1, 2009. Published July 2009. Originally approvedin 1998. Last previous edition approved in 2002 as F 1888 02.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
15、refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 Compression Force Gauge, to measure the compressiveload in newtons or pounds. Device must be able to measure atleast
16、1000 lb (4448 N).6.3 Compression-Displacement Gauge, to measure the dis-placement at the prescribed level of 0.25 in. (6.35 mm).6.4 Motor, Drive, and Speed Control, to drive the compres-sion device to 0.25 in. (6.35 mm) displacement in a time of 12to 18 s at a constant rate.6.5 A Steel Tape, 0.25 in
17、. (6.35 mm) wide, suitable formeasuring lengths to the nearest 0.0625 in. (1.5875 mm).7. Conditioning7.1 Ball Conditioning and Test Room Conditions:7.1.1 Test balls shall be stored in an environmentallycontrolled space for at least 14 days immediately beforetesting.7.1.2 Temperature is to be maintai
18、ned at 72 6 4F (22 62C).7.1.3 Relative humidity is to be maintained at between 40and 60 %.7.1.4 Temperature and humidity are to be measured andrecorded hourly within 60.5F (60.3C) and 62 % RH overconditioning and test duration.8. Procedure8.1 Wrap the steel tape around the middle of the ball tomeasu
19、re the circumference twice over two seams (each mea-surement taken 90 apart) and once over four seams. Recorddata to the nearest 0.0625 in. (1.5875 mm). Average the threemeasurements to obtain the final size measurement.8.2 Orient the ball in the compression press to align thevertical axis of the ba
20、ll with the vertical axis of the compress-ing piston, and orient the ball so that compression occursbetween ball seams.8.3 Activate the compression press until the upper plate is incontact with the ball with a 1-lb (4.45-N) preload for expectedcompression values less than 150 lb (667.5 N) 6 5 % and
21、a4-lb (17.8-N) preload for expected compression values greaterthan 150 lb (667.5 N) 6 5 % applied to the ball.8.4 Set the compression displacement gage reading to zero.8.5 Compress the ball to a displacement of 0.25 in. (6.35mm) in 12 to 18 s at a constant rate and record the peak forceapplied at th
22、at level of displacement.8.6 Release the applied load, rotate the ball 90 and repeat8.2-8.4.NOTE 2Depending on the materials of construction, the compression-displacement may change with repeated compressions. For this reason, theprocedure is limited to two compressions, on two different axis of the
23、 testballs.9. Calculation9.1 Ball compression is calculated as the average of the twomeasured forces required to compress the test ball 0.25 in.(6.35 mm) on two different axis of the ball.10. Report10.1 Report the following information:10.1.1 Name of the test facility and test operator,10.1.2 Test d
24、ate,10.1.3 Hourly measurements of test conditions, including:10.1.3.1 Relative humidity and temperature of the ballconditioning and test room environments,10.1.3.2 Number of hours ball was in conditioning environ-ment.10.1.4 Test equipment used for this test method,10.1.5 Test ball information, mode
25、l, weight tested, and anyother pertinent data such as condition of the ball,10.1.6 Average ball compression in accordance with Section9 of this standard.10.1.7 Any and all unique observations, including but notexclusively, any damage to the ball, and10.1.8 Calibration certificate numbers for measure
26、ment de-vices.11. Precision and Bias311.1 The precision of this test method is based on aninterlaboratory study conducted in 2008. Each of six laborato-ries tested ten different baseballs. Every “test result” representsan individual determination. Each laboratory reported threereplicate test results
27、 for the analyses. Practice E 691 wasfollowed for the design and analysis of the data; the details aregiven in the research report footnoted above.11.1.1 Repeatability Limit (r)Two test results obtainedwithin one laboratory shall be judged not equivalent if theydiffer by more than the “r” value for
28、that material; “r”istheinterval representing the critical difference between two testresults for the same material, obtained by the same operatorusing the same equipment on the same day in the samelaboratory.11.1.1.1 Repeatability limits are listed in Table 1.11.1.2 Reproducibility Limit (R)Two test
29、 results shall bejudged not equivalent if they differ by more than the “R” valuefor that material; “R” is the interval representing the criticaldifference between two test results for the same material,obtained by different operators using different equipment indifferent laboratories.11.1.2.1 Reprod
30、ucibility limits are listed in Table 1.11.1.3 The terms repeatability limit and reproducibility limitare used as specified in Practice E 177.11.1.4 Any judgment in accordance with statements 11.1.1and 11.1.2 would have an approximate 95 % probability ofbeing correct.12. Keywords12.1 baseballs; compr
31、ession-displacement; softballs3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: F08-1009.F1888092ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin t
32、his 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 the responsible technical committee and must
33、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 receive careful consideration at a meeting of there
34、sponsible 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 International, 100 Barr Harbor Drive, PO Box C700,
35、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).TABLE 1 Compr
36、ession (lb)BallAverage,xRepeatabilityStandardDeviation, SrReproducibilityStandardDeviation, SRRepeatabilityLimit, rReproducibilityLimit, RBall 1 206.65 11.95 22.36 33.45 62.61Ball 2 205.40 13.27 20.52 37.17 57.45Ball 3 206.50 14.68 27.38 41.11 76.68Ball 4 203.47 14.30 19.42 40.05 54.37Ball 5 213.07 14.38 20.01 40.26 56.03Ball 6 211.52 11.04 25.40 30.92 71.11Ball 7 225.49 16.86 27.46 47.20 76.88Ball 8 222.92 12.18 21.43 34.11 60.01Ball 9 220.54 13.63 26.70 38.18 74.76Ball 10 219.45 12.50 25.19 35.01 70.52Average 213.50 13.48 23.59 37.75 66.04F1888093
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