Ametek Surtronic 25, User Manual

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Surtronic S25
Ra, Rp, Rsm, Rz, Rt, Rmr, RPc, Rz1max, Rsk, Rda
Additional parameters can be analysed by downloading results to
optional software.
Ra.
Ra is the universally recognised, and most used, international
parameter of roughness. It is the arithmetic mean of the absolute
departures of the roughness profile from the mean line.
Rp.
Maximum Profile Peak Height
Mathematically, the Largest Peak Deviation of the Roughness
Profile from the Mean Line within a Sampling Length.
When more than one Sampling Length is analysed Rp is the mean
value of the individual Rp values for each sample.
RSm.
RSm is the mean spacing between profile peaks at the mean
line, measured within the sampling length. (A profile peak is the
highest point of the profile between an upwards and downwards
crossing of the mean line).
Rz.
Rz = Rp + Rv and is the maximum peak to valley height of the
profile within a sampling length
When more than one Sampling Length is analysed Rz is the mean
value of the individual Rz values for each Sampling Length.
Rz1max.
Maximum Height of Profile
Highest peak to valley within a sampling length. When measured
over several sampling lengths the largest individual sampling
length value is taken.
Also known in the past as Rymax, Ry, Rmax or Rti
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