ASTM F1888-2002 Test Method for Compression-Displacement of Baseballs and Softballs《棒球和垒球受压位移的试验方法》.pdf

1、Designation: F 1888 02An American National StandardTest 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 revision, the y

2、ear 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 test method describes a comparative measurementmethod for baseballs and softballs as defined by a staticc

3、ompression 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 influence th

4、e performance characteristics, this test provides asimple method to compare and categorize such balls based on force levelsin a standardized compression-displacement test.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility

5、 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.2. Terminology2.1 Definitions of Terms Specific to This Standard:2.1.1 baseballs and softballs, nany such ball defined bythe rules of the game a

6、s published by the sports governingbodies.2.1.2 compression-displacement, nthe reduction in balldiameter under a specified compressive load between two flatplates. Synonymous with compression-deflection.2.1.3 force, nthe resistance to displacement. The interac-tion between test machine and ball duri

7、ng compression.3. Summary of Test Method3.1 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 recorded.4. Significance and

8、 Use4.1 The static compression-displacement of a baseball orsoftball is a mechanical property which can correlate todynamic properties.4.2 This test method is suitable for obtaining data inresearch and development, quality control, and classifyingballs by the compression-displacement.4.3 Sports asso

9、ciations can use compression-displacementstandards in specifications for official baseballs and softballsstandards in specifications for official baseballs and softballsfor purposes of consistency of performance.4.4 This same test procedure can be utilized with othercompressive forces and the specif

10、ied force is not necessarilythe same as experienced in actual use.5. Apparatus5.1 Compression Device, to compress the test ball betweentwo flat plates to 6.35 mm (0.25 in.) displacement. Compres-sive force to 3560 N (800 lb) is sufficient. A means of centeringthe test ball so that the vertical axis

11、of the ball aligns with thevertical axis of the compression device piston.5.2 Compression Force Gage, to measure the compressiveload in newtons or pounds. Device must be able to measure atleast 4448 N (1000 lb).5.3 Compression-Displacement Gage, to measure the dis-placement at the prescribed level o

12、f 6.35 mm (0.25 in.).5.4 Motor, Drive, and Speed Control, to drive the compres-sion device to 6.35 mm (0.25 in.) displacement in a time of 12to 18 s at a constant rate.6. Conditioning6.1 Ball Conditioning:6.1.1 Store test balls at the test environmental conditions forat least 24 h prior to testing.6

13、1.2 Maintain test environment temperature at 22 6 2C(72 6 4F).6.1.3 Maintain test environment relative humidity at 50 610 %.6.2 Test Room Conditions:6.2.1 Maintain test room temperature at 22 6 2C (72 64F).1This test method is under the jurisdiction of ASTM Committee F08 on SportsEquipment and Faci

14、lities and is the direct responsibility of Subcommittee F08.26 onBaseball and Softball Equipment and Facilities.Current edition approved Dec. 10, 2002. Published January 2003. Originallyapproved in 1998. Last previous edition approved in 1998 as F 1888 98.1Copyright ASTM International, 100 Barr Harb

15、or Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2.2 Maintain test room relative humidity between 20 and60 %.7. Procedure7.1 Orient the ball in the compression press to align thevertical axis of the ball with the vertical axis of the compress-ing piston, and orient the ball s

16、o that compression occursbetween ball seams.7.2 Activate the compression press until the upper plate is incontact with the ball with a 4.45-N (1-lb) preload for expectedcompression values less than 667.5 N (150 lb) 6 5 % and a17.8-N (4-lb) preload for expected compression values greaterthan 667.5 N

17、150 lb) 6 5 % applied to the ball.7.3 Set the compression displacement gage reading to zero.7.4 Compress the ball to a displacement of 6.35 mm (0.25in.) in 12 to 18 s at a constant rate and record the peak loadforce applied at that level of displacement.7.5 Release the applied load, rotate the ball

18、 90 and repeat7.1-7.3.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 testballs.8. Calculation8.1 Ball compression is calculated as the ave

19、rage of the twomeasured forces required to compress the test ball 6.35 mm(0.25 in.) on two different axis of the ball.9. Precision and Bias9.1 Precision and bias evaluations have not been conductedfor this test method. When such data are available, a precisionand bias section will be added.10. Keywo

20、rds10.1 baseballs; compression-displacement; softballsASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent r

21、ights, 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 be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either f

22、or 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 theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair heari

23、ng 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, 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).F1888022