ASTM_F_780_-_93a_2012.pdf

Designation:F78093a(Reapproved 2012)Standard Test Method forLinear Deformation and Breaking Strength of Alpine Skis1This standard is issued under the fixed designation F780;the number immediately following the designation indicates the year of originaladoption or,in the case of revision,the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of lineardeformation load and breaking load for Alpine skis.21.2 This test method is applicable to all Alpine skis.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-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3D2240 Test Method for Rubber PropertyDurometer Hard-nessF472 Terminology for Geometry of Alpine Skis3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 breaking load(FB)the maximum load applied inaccordance with Sections 6 and 7(that is,the maximum loadwhich the ski can sustain).3.1.2 deformation load(FD)the load applied in accor-dance with Section 6 that causes a permanent deformation of 1mm at the load application point of the ski.4.Significance and Use4.1 This test method provides information concerning theresistance of a ski to permanent bending and an indication of itsbasic strength.It is not intended to evaluate the data withregard to the quality of the ski.5.Apparatus5.1 This test method shall be conducted on a device(seeFig.1)equipped with adjustable supports,a load(F)applica-tion system(1)with a range of at least 20 000 N and readingaccuracy of 650 N,and with an instrument(2)for readingbending deformation(d)with an accuracy of 0.01 mm.Thesystem must have a controlled deflection rate.A standarduniversal tension/compression testing machine with X Yrecorder(3)is typical of such a system.5.2 The test method is made with the ski in its normalhorizontal position,and the overhanging portions of the ski areleft free to deflect.5.3 The test system shall be set up in accordance with Fig.1(Section A)with a 250-mm distance between supports andone support made with a 25-mm diameter,low-friction roller atpoint of contact with the ski.The end support shall be sodesigned as to have a hinged clamp which prohibits lineardisplacement,yet permits rotation about the support.The loadis applied through a plate as shown in Fig.1(Section B),25mm wide and of length equal to or slightly greater than thewidth of the ski,made up of a steel plate(5)and a hard rubber(95 6 5 ShoreAdurometer;see Test Method D2240)layer(4).The plate must be free to rotate under loading ram.6.Determination of Load Application Point6.1 In order to obtain comparable values,the test shall beconducted at the load application point with a separationbetween the supports of 250 6 0.5 mm.Determine the loadapplication point by moving the ski in a longitudinal directionon the supports until a deflection is obtained under a load of600 6 5 N in accordance with the table shown below:Ski Length,LN,mm(see Terminology F472)Deflection,mmTolerance,mm1700#LN20.031400#LN 170040.031000#LN 140060.030750#LN 100080.037.Procedure7.1 Condition the ski for 24 h minimum at a temperature of23 6 5C.Place the ski as shown in Fig.1,and set up thesystem to apply the load midway between the supports.Thestiffness of the ski at point of loading must be within the 3%1This test method is under the jurisdiction of ASTM Committee F27 on SnowSkiing and is the direct responsibility of F27.30 on Skis and Boots.Current edition approved March 1,2012.Published April 2012.Originallyapproved in 1982.Last previous edition approved in 2006 as F780 93a(2006).DOI:10.1520/F0780-93AR12.2This test method is meant to conform in all meaningful ways to the ISOstandard ISO/DIS 6265,available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 tolerance under a load of 600 6 5 N;noncomparable informa-tion will result otherwise.Load the ski at a rate sufficient toincrease the deflection by 25 6 5 mm/min,until the loaddeflection curve changes to a negative slope indicating failureof the ski.8.Interpretation of Results8.1 The test data obtained from a load-deflection diagram isshown in Fig.2.The deformation load,FD,is determined bydrawing a straight line parallel to the linear portion of theload-deflection diagram through that point on the abscissawhich equals a