Pinnakareduse standardid (2)

Surface TextureContour Measuring Instruments
Explanation of Surface CharacteristicsStandards
Definition of Surface texture and Stylus instrument Profile by Stylus and phase correct filter ISO4287: '97 and ISO3274: '96 Total profile Primary profile P Measure perpendicular to lay
X axis Z axis Stylus method Form deviation profile probe P- parameter = Mean line for roughness profile =Waviness profile on old DIN & JIS s profile filter
Real surface c profile filter
f profile filter Traced profile · Stylus deformation Phase correct filter 50% perpendicular · Noise transmission at cutoff to real surface No phase shift / low distortion
rtip Waviness profile W Roughness profile R ( Filtered center line waviness profile)
R-parameter W-parameter
Stylus tip geometry 100% Transmission
= 60° (or 90°) cone rtip = 2m (or 5, 10m) Roughness profile Waviness profile
50%
0 s c Wavelength f Selection of c & Stylus Tip rtip Cutoff (Wavelength) c c (mm) c/s rtip (m) 0.08 30 2 0.25 2.5 100 0.8 2 (5 at RZ > 3m) 2.5 8 300 5 or 2 Surface Texture Contour Measuring Instruments
8 25 10, 5 or 2
Evaluation procedure of roughness ISO4288: '96 1. View the surface and decide whether profile is periodic or non- periodic. Upper limit - the 16% rule (Default) 2. When the tolerance limit is specified, use the table shown on the left Measure on the most critical surface. If not more than 16% of all value for condition . based on sampling length are exceed the limit, surface is acceptable. 3. When the tolerance limit is not specified. - The first value does not exceed 70% of the limit. 3.1 Estimate roughness and measure it in corresponding condition in - The first three values do not exceed the limit. - Not more than one of the first six value exceed the limit. the table. - Not more than two of the first twelve value exceed the limit. 3.2 Change condition according with above result and measure it or when + does not exceed the limit, the result is acceptable. again . 3.3 Repeat "3.2" if the result does not reached the condition. 3.4 When the result reaches the condition, it will be the final value. Lower limit - the 16% rule (shown as L) Check it in shorter sampling length at non-periodic and change it Measure the surface that can be expected the lowest roughness. if it meets. If not more than 16% of all sampling length are less than the limit, 4. Compare the result toward tolerance limit in accordance with following or when - is not less than the limit, the result is acceptable. rule, Max value - the max rule (when "max" suffix is added) The value is acceptable when none of value in entire surface is over the limit.
230 Sampling length and Evaluation length Mean line ISO4287: '97 Primary profile P
Top of profile peak Roughness profile R Profile Mean line peak
Profile valley Sampling length Rr Bottom of Profile element width Xs = Cutoff c profile valley Rr Rr Rr Rr
Evaluation length Rnn×Rr (n: Default 5)
Pre travel Tracing length LtLpLnLp Post travel Rp (c/2) Rp (c/2)
Indication of surface texture Note.: Default item (red) is not indicated. ISO 1302: '02 Additional item (blue) is indicated if necessary.
not allowed Required Manufacturing method Surface parameter and condition
c ground Material removal Example a U 0.008 - 2.5/Rz3max 12.3 e d b 3 L"2RC"0.008 - 0.8/Ra75 0.2
Machining The second surface parameter allowance (mm) Surface lay and orientation and condition ,, X, M, C, R, P
Upper U Filter Phase correct Transmission band No. of S. length Comparison Parameter
Surface Texture Contour Measuring Instruments s - c (mm) Value limit or or n rule (m) Lower L 2RC Default is table below Profile Type (Default 5) 16% or max
U "2RC" 0.008 ­ 2.5/ R z3max 12.3
Measuring condition: R-parameter Measuring condition : P-parameter ISO4288: '96 ISO4288: '96 Non-periodic profile Measuring Condition Stylus No. of S. length E. length Periodic profile s c Rp = n Rp Rn radius Ra,Rq,Rsk,Rku Rz,Rv,Rp,Rc, or RSm or Rq or Rt Sampling Evaluation 2m 2.5m length: length Length of Length of Rr = Rn (mm) = 5m 8m ­ 1 feature feature Ra (m) Rz (m) RSm (mm) CutOff 5 ×Rr 10m 25m ( Plane , Line) Over> Less Over> Less Over> Less c (mm)
0.006 0.02 0.025 0.1 0.013 0.04 0.08 0.4 Measuring condition: W-parameter , ISO1302: 02 0.02 0.1 0.1 0.5 0.04 0.13 0.25 1.25 No. of 0.1 2 0.5 10 0.13 0.4 0.8 4 c f Rw = m S. length Rw E. length Rn 2 10 10 50 0.4 1.3 2.5 12.5 c nc m: specified 10 80 50 200 1.3 4 8 40 (for roughness) (n: specified) f mf
231 Surface TextureContour Measuring Instruments
Explanation of Surface CharacteristicsStandards
Basic surface texture parameters and curves Amplitude parameters (peak and valley) Amplitude average parameters
Rp Rt Ra Pp Maximum profile peak height Pt Total height of profile Pa Arithmetical mean deviation Wp Wt (Pt = Rmax at JIS'82) Wa The largest profile peak height Zp within a Sum of height of the largest profile peak height Arithmetic mean of the absolute ordinate sampling length. Rp and the largest profile valley Rv within an values Z(x) within a sampling length. evaluation length. 1 L Rp, Pp, Wp = max (Z(x)) Rt, Pt, Wt = max (Rpi) + max (Rvi) Ra, Pa, Wa = Z (x) dx L 0
Rp Rp5 Rp2 Zp1 Zp2 Zpi Ra Rt
rr Rv2 Rv4 Sampling length L Sampling length L Evaluation length Rn
Rv Rc Rq Pv Maximum profile valley depth Pc Mean height of profile elements Pq Root mean square deviation Wv Wc Wq The largest profile valley depth Zp within a Mean value of the profile element heights Zt Root mean square value of the ordinate values sampling length. within a sampling length. Z(x) within a sampling length. 1 m Rc, Pc, Wc = Zti Rq, Pq, Wq = 1 L Z2 (x) dx Rv, Pv, Wv = min (Z(x)) m l=1 L 0 Zti Zt1 Zt2 Ztm Zt3
Rq2 Rv
Zv1 Zv2 Zvi Sampling length L Surface Texture Contour Measuring Instruments
Sampling length L
Profile element: Profile peak & the adjacent valley Sampling length L
Rz Rz jis Ten point height of roughness profile Ra75 Center line average Pz Maximum height of profile (Rz at JIS'94) (Old Ra, AA, CLA) Wz (Rz = Ry at ISO4287 '84) Sum of mean value of largest peak to the fifth Arithmetic mean of the absolute ordinate value largest peak and mean value of largest valley to Z(x) in a sampling length of roughness profile Sum of height of the largest profile peak height the fifth largest valley within a sampling length. with 2RC filter of 75% transmission. Rp and the largest profile valley Rv within a sampling length. Rz jis= 1 (Zpj + Zv j) 5 1 rn
Rz = Rp + Rv 5 j=1 Ra75= Z (x) dx rn 0
Zp 1st Zp2nd Zp3rd Zp4th Rp Zp5th Ra75
Rz Rzjis
Rv Zv5th Zv3rd Zv4th Zv2nd Zv1st Sampling length L Sampling length L Sampling length L
Different from Rz at old ISO, ANSI & JIS Annex of JIS only and confirm to JIS'94 Annex of JIS only Different from Rz at JIS'82 Same as Ra at old ISO, ANSI & DIN
232 Spacing parameters Hybrid parameters Height characteristic average parameters
RSm Rq Rsk PSm Mean width of the profile elements Pq Root mean square slope Psk Skewness WSm (RSm = Sm at ISO4287 '84) Wq Wsk Mean value of the profile element width Xs Root mean square value of the ordinate slopes Quotient of mean cube value of the ordinate within a sampling length. dZ/dX within a sampling length. values Z(x) and cube Pq, Rq, Wq respectively, within a sampling length.
1 m Rq 1 1 Rr 3 RSm, PSm, WSm = Xsi 1 L d 2 Rsk = Z (x) dx m i=1 Pq = Z (x) dx Rq3 Rr 0
Wq L 0 dx Xs1 Xs2 Xs3 Xsi Xsm dZ (x) / dx Rsk > 0
Rsk Probability density
Parameter from bearing ratio curve and profile height amplitude curve Rku Pku Kurtosis of profile Material ratio curve of the profile Profile height amplitude curve Wku ( Abbott Firestone curve) Quotient of mean quartic of the ordinate values Curve representing the material ratio of the Sample probability density function of ordinate Z(x) and 4th power of Pq, Rq, Wq respectively, profile as a functional of level c. Z(x) within an evaluation length. within a sampling length.
1 1 Rr 4 Rku = Z (x) dx Rq4 Rr 0 Mr(c) 1 Mr(c) i 0% c
Rt Rku > 3
100% 0% 100% 0 Probability Rku Surface Texture Contour Measuring Instruments Evaluation length Rn density Rmr (c) Profile Bearing ratio curve Profile height amplitude curve Probability density
Rmr Rmr(c) Rc Pmr(c) Material ratio of profile Pc Profile section height difference Pmr Relative material ratio Wmr(c) (Rmr(c) = ex- tp) Wc Wmr Ratio of the material length of the profile Vertical distance between two section levels of Material ratio determined at a profile section elements Ml(c) at a given level c to the given material ratio. level Rc, related to a reference c0.