1、September 2013Translation by DIN-Sprachendienst.English price group 9No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).IC
2、S 97.220.20!%( b) in Subclauses 6.1, 6.2, 6.3 and 6.4, requirements for the load application have been extended and it is now allowed for certain models to change the load application points; c) the standard has been editorially revised. Previous editions DIN 7886: 1978-11 DIN ISO 5902: 1981-12 3DIN
3、 ISO 5902:2013-09National Annex NA (informative) Bibliography DIN ISO 6289, Skis Vocabulary 4DIN ISO 5902:2013-091 ScopeThis International Standard specifies laboratory measurement methods to determine the elastic properties of alpine skis. Its purpose is to calculate the resistance of defined parts
4、 of the ski to bending and torsion.The standard measurement procedures are recommended in order to ensure comparability between laboratory measurement data determined and published by ski manufacturers, institutions and others. In this International Standard no attempt is made to relate the measurem
5、ent data to the quality of the ski.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the refere
6、nced document (including any amendments) applies.ISO 6289, Skis Vocabulary3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1spring constantcratio of the force F applied to the ski, to the corresponding deflection f:cFf= Note 1 to entry: Depending
7、on the individual parts of the ski on which the force F is applied, one can define: the centre spring constant, cM; the shovel spring constant, cS; the rear spring constant, cR; the afterbody spring constant, cA; the forebody spring constant, cB.Note 2 to entry: See Figure 1.Alpine skis Determinatio
8、n of elastic properties 5DIN ISO 5902:2013-09KeyA afterbody spring bending lineB forebody spring bending lineM centre spring bending lineR rear spring bending lineS shovel spring bending lineFigure 1 Indices for spring constants3.2spring constant balanceBratio of the afterbody spring constant, cA, t
9、o the forebody spring constant, cBBcc=AB3.3torsional spring constantcTratio of the torque applied to the ski to the corresponding torsion angle cMT=4 Apparatus4.1 The apparatus for measuring the centre spring constant shall consist of the following items.4.1.1 Two adjustable supports with low-fricti
10、on rollers of 20 mm diameter and wide enough to ensure that the test ski can be supported on its whole width. One of the supports with low-friction rollers has a device for clamping the end of the ski.4.1.2 A load application device with an accuracy of 2 N for application of the test force FMmid-way
11、 between the supports, which are placed at a distance that is adjustable between 1 200 and 1 720 mm, by means of a contact ram with a radius of 10 mm and a width touching the whole width of the test ski.4.1.3 A linear measuring device for measuring the deflection f with an accuracy of 0,5 mm.6DIN IS
12、O 5902:2013-094.2 The apparatus for measuring the shovel, rear, afterbody and forebody spring constants shall consist of the following items.4.2.1 A clamping device, consisting of a flat jaw and three clamps, ensuring that the whole width of the ski can be clamped (see Figure 2).4.2.2 A load applica
13、tion device with an accuracy of 2 N for application of the test forces FS, FR, FAor FBat a distance that is adjustable between 330 mm and 860 mm from the edge of the flat jaw of the clamping device by means of a low-friction roller of 20 mm diameter and wide enough to touch the whole width of the te
14、st ski.4.2.3 A linear measuring device as specified in 4.1 c).Dimensions in millimetres123 Key1 clamps2 test ski3 flat jawFigure 2 Clamping device for bending and torque tests of alpine ski Minimal dimensions4.3 The apparatus for measuring the torsional spring constant shall consist of the following
15、 items.4.3.1 A clamping device as specified in 4.2 a) and shown in Figure 2.4.3.2 A torsion head of low friction with an accuracy of 2 Nm for application of the torque M at a distance, adjustable between 610 mm and 860 mm from the edge of the flat jaw of the clamping device. The clamping device of t
16、he torsion head holds the running surface at the same level as the clamping device of the centre of the ski (see Figure 3).4.3.3 A scale to read the torsion angle with an accuracy of 0,5.7DIN ISO 5902:2013-0912Key1 test ski2 ski axis3 width of skiFigure 3 Torsion head for the torque test of alpine s
17、ki5 Sampling and conditioningAll measurements according to this International Standard shall be taken from a finished ski without any mounted parts.lt is recommended that one of the following sizes of ski be used:150, 180 or 200 cm.From these three sizes shall be selected the size that is nearest in
18、 length to the model that is submitted for testing.Before testing, the test ski shall be conditioned for at least 2 h at a temperature of 23 C 5 C.6 Procedure6.1 Determination of centre spring constant, cMDetermine the nominal length, LN, in accordance with ISO 6289. Place the ski on two supports se
19、t at a distance of LN 280 mm using the apparatus specified in 4.1 and clamp at a distance of 50 mm from the end of the ski (see Figure 4). It is allowed for certain models to change the 50 mm and this shall be mentioned in the test report.8DIN ISO 5902:2013-09Dimensions in millimetresKey1 clamping d
20、eviceFigure 4 Determination of centre spring constant, cMApply a pre-load of 20 N. Load the ski quasi-statically with the rate of deflection less than 20 mm/min, with a test load of FM= 300 N. Read the deflection, fM, in millimetres, caused by the test load, FM, within 2 s to 5 s after the test load
21、 has been applied.6.2 Determination of shovel spring constant, cSClamp the ski in the apparatus specified in 4.2 at a projected distance of 120 mm between ski tip and load application roller, after having set a distance of 0,3 LN 120 mm between the clamping device and the load application roller, as
22、 shown in Figure 5. It is allowed for certain models to change the 120 mm and this shall be mentioned in the test report.Dimensions in millimetresFigure 5 Determination of shovel spring constant, cSApply a pre-load of 20 N. Load the ski quasi-statically, with the rate of deflection less than 20 mm/m
23、in, with a test load of FS= 150 N. If the deflection is more than 50 mm, the load should be reduced to 100 N. Read the deflection, fS, in millimetres, caused by the test load FS, within 2 s to 5 s after the test load has been applied.9DIN ISO 5902:2013-096.3 Determination of rear spring constant, cR
24、Clamp the ski in the apparatus specified in 4.2 at a projected distance of 10 mm between the ski tail and the load application roller, after having set a distance of 0,3 LN 120 mm between the clamping device and the load application roller, as shown in Figure 6. It is allowed for certain models to c
25、hange the 10 mm and this shall be mentioned in the test report. For a ski with high tail turn up, the load application point is found by determining the point of the running surface which is 5 mm above a flat standing surface and 10 mm forward from that point.Dimensions in millimetresFigure 6 Determ
26、ination of rear spring constant, cRApply a pre-load of 20 N. Load the ski quasi-statically with the rate of deflection less than 20 mm/min, with a test load of FS= 150 N. If the deflection is more than 50 mm, the load should be reduced to 100 N. Read the deflection fR, in millimetres, caused by the
27、test load FRwithin 2 s to 5 s after the test load has been applied.6.4 Determination of spring constant balance, B (forebody and afterbody spring constants)Make two bending tests, loading first the afterbody and then the forebody of the ski. Use the apparatus specified in 4.2, setting the clamping d
28、evice and the load application roller at a distance of 0,5 LN 140 mm. The clamping point for the afterbody spring constant as well as for the forebody spring constant shall be 0,5 LN 140 mm + 50 mm from the ski tail (see Figure 7). Mount the ski on the clamping device in such a way that the ski afte
29、rbody or ski forebody can be bent freely from the clamping point. It is allowed for certain models to change the 50 mm and this shall be mentioned in the test report.10DIN ISO 5902:2013-09Dimensions in millimetresFigure 7 Determination of spring constant balance, B (forebody and afterbody spring con
30、stants)Apply a pre-load of 20 N. Load the ski quasi-statically with the rate of deflection less than 20 mm/min, with a test load of FAor FB= 50 N. Read the deflection fAor fScaused by the test load FAor FBwithin 2 s to 5 s after the test load has been applied.6.5 Determination of forebody torsional
31、spring constant, cTB, and afterbody torsional spring constant, cTAUse the apparatus specified in 4.3, setting a distance of 0,5 LN 140 mm between the clamping device and the torsion head. Clamp the ski in the measurement device as shown in Figure 8. The axis of the ski shall be in the centre of the
32、torsion head.11DIN ISO 5902:2013-09Dimensions in millimetresFigure 8 Determination of forebody torsional spring constant, cTB, and afterbody torsional spring constant, cTAApply a torque quasi-statically with the rate of deflection less than 20 mm/min, (in the case of very stiff skis a torque of 20 N
33、m is recommended if the torsion angle is less than 5). Read the torsion angle within 2 s to 5 s after the torque has been applied.7 Expression of resultsFor each property, calculate the single results of three tests, in accordance with Clause 3, recording their mean. Recommended units are given in T
34、able 1.Table 1 Recommended unitsCharacteristic UnitSpring constant, c N/mmTorsional spring constant, cTNm/8 TolerancesIf data are published by the manufacturer with reference to this International Standard, the following tolerances shall be observed: spring constant 10 % torsional spring constant 10
35、 %12DIN ISO 5902:2013-099 Test reportThe test report shall include the following particulars:a) reference to this International Standard, i.e. ISO 5902;b) name or trademark of the manufacturer;c) model designation;d) nominal length;e) manufacturers registration number;f) test results;g) any deviation from this International Standard with an explanation of the reason for the deviation.13DIN ISO 5902:2013-09
