Ametek Surtronic 25 User manual

Surtronic 25
User’s Guide
K505/125-01 Issue 4
Taylor Hobson Ltd
POBox 36, 2 New Star Road, Thurmaston, Leicester
LE49JQ, England
Telephone[phone], Fax [phone]
E-mail:[email protected]
www.taylor-hobson.com

Surtronic S25
Chapter 1 Introduction to
Surface Texture terminology
and definition s ............................1-1
SurfaceTexture Definitions ......................1-1
ParameterDefinitions ...............................1-3
Ra
......................................................... 1-3
Rp
......................................................... 1-3
RSm
..................................................... 1-3
Rz
......................................................... 1-3
Rz1max ................................................
1-3
Rt
.......................................................... 1-4
Rmr
...................................................... 1-4
RPc
...................................................... 1-4
Rsk
....................................................... 1-4
Rda
....................................................... 1-5
Chapter 2 Description ...............2-1
TheEquipment ........................................... 2-2
Traverse Unit ...................................... 2-2
Pick-up Mounting Components .......... 2-3
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Surtronic S25
Mounting Bracket
................................. 2-4
AdjustableSupport
............................... 2-5
Pick-upholder ......................................
2-5
Connector
............................................. 2-6
Pick-up
................................................. 2-6
Mounting............................................. 2-8
Chapter 3 Getting Started ........ 3-1
Battery
........................................................ 3-1
Connecting the Pick-up ............................. 3-1
Making a measurement
............................. 3-2
Switching the Surtronic 25 ON ........... 3-2
Tocancel a measurement ..................
3-4
Using the Surtronic 25 with a PC
............. 3-4
Printing
....................................................... 3-4
Tocancel print:
..................................... 3-5
Chapter 4 Menu Settings .......... 4-1
Main Menu
.................................................. 4-1
Cutoff....................................................
4-1
Evaluationlength...................................
4-1
Parameters............................................ 4-1
Range:
.................................................. 4-4
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Surtronic S25
RangeSelector Table ........................
4-4
PrintSettings: ....................................... 4-4
Units: ....................................................
4-4
Filter: ....................................................
4-4
Dump Mode: .........................................
4-5
DumpMode (Using your Surtronic 25
witha PC) ...........................................
4-5
SPCMode ...................................................
4-5
LanguageSettings
.................................... 4-6
Chapter 5 Making Measurements -
Technical Considerations .........5-1
OperatingNotes .........................................
5-1
Ona horizontal surface ...................... 5-1
Onother surfaces ...............................
5-2
Cutoff: ................................................
5-2
Evaluation Length: ............................. 5-3
Tableof Cut-off values .......................
5-3
OperatingError Indications ......................
5-4
Specification ..............................................
5-6
RS232Output .............................................
5-7
PrinterConfiguration .......................... 5-7
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Surtronic S25
Specification for Data Dump ..................... 5-8
Chapter 6 Accessories ............. 6-1
Alternative standard pick-up (112/1503) ..6-1
Smallbore pick-up, 5mm (200min) stylus
tip radius (112/1504)
.................................. 6-1
SmallBore Pick-up (112/2673)
................. 6-1
NarrowGauge Stylus (155/P11610)
......... 6-2
RightAngle Pick-up, 5mm (200min) stylus
tip radius (112/1505)
.................................. 6-2
Recesspick-up, 5mm (200min) stylus tip
radius (112/1506)
....................................... 6-3
Recesspick-up (112/2672)
........................ 6-4
Chiseledge pick-up (112/1524)
................ 6-4
Side-skidpick-up (112/1531)
.................... 6-5
ShoePick-up (112/1599)
........................... 6-6
Detachable Skid (112/1191) ...................... 6-7
Extensionrod (112/1533)
.......................... 6-7
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Surtronic S25
PortablePrinter 112/3469-01 ....................6-8
ReplicaKit (112/727) .................................. 6-9
Portablebase (137/1734)
........................... 6-10
Chapter 7 Maintenance .............7-1
Calibration .................................................. 7-1
Reference Standard ...........................7-1
Sensitivity Check and Adjustment ......7-1
Pick-up with Chisel Edge Stylus .........7-2
Cleaningthe Stylus
................................... 7-2
Pick-upSkid ............................................... 7-2
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Surtronic S25
Page vi

Chapter 1
Surtronic S25
Introduction to Surface Texture
terminology and definitions
SurfaceTexture Definitions
Every components surface has some form of texture which varies
according to its structure and the way it has been manufactured.
These surfaces can be broken down into three main categories:
Surface roughness, Waviness and Form. In order to predict a
components behaviour during use or to control the manufacturing
process, it is necessary to quantify these surface characteristics.
This is done by using surface texture parameters.
Surface texture parameters can be separated into three basic types:
Amplitude, Spacing and Hybrid.
Amplitude Parameters. are measures of the vertical
characteristics of the surface deviations.
Spacing Parameters. are measures of the horizontal character-
istics of the surface deviations.
Hybrid Parameters. are combinations of spacing and
amplitude parameters.
Mean Line. the mean line is a least squares line of nominal form
fitted through the primary profile where the areas of the profile
above and below this line are equal and kept to a minimum
separation. Profile filters as detailed in ISO11562 define the mean
lines for the roughness and waviness profiles.
Cut-off. A cut-off length (or sampling length) is a filter that uses
either electronic (2CR) or mathematical (Gaussian) means to
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Surtronic S25
remove or reduce unwanted data in order to look at wavelengths in
the region of interest.
Bandwidth. Bandwidth is the ratio of the upper Cut-off (Lc) to
the lower Cut-off (Ls).
Sample Length. The profile is divided into sample lengths l,
which are long enough to include a statistically reliable amount of
data. For roughness and waviness analysis, the sample length is
equal to the selected cut-off (lc) wavelength. The sample length is
also known as the cut-off length.
Evaluation Length. The length in the direction of the X axis
used for assessing the profile under evaluation. The evaluation
length may contain one or more sample lengths. For the primary
profiles the evaluation length is equal to the sample length.
Note: almost all parameters are defined over one sample length,
however in practice more than one sample length is assessed
(usually five) and the mean calculated. This provides a better
statistical estimate of the parameters measured value.
ISO 3274-1996, ISO 4287-1997, ISO 4288-1996, ISO 11 562 and
other International Standards are followed where appropriate by
Taylor Hobson equipment.
More detailed information on surface texture in general and on
stylus-type measuring instruments in particular is covered in the
book 'Exploring Surface Texture', published by Taylor Hobson.
ParameterDefinitions
Surface texture is quantified by parameters which relate to certain
characteristics of the texture. The Surtronic 25 offers the
following parameters:
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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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Surtronic S25
Rt. Total Height of the Profile.
Rt is the Maximum Peak to Valley Height of the Profile in the
Assessment (evaluation) Length (ln).
Rmr. Material Ratio is the length of bearing surface (expressed
as a percentage of the evaluation length ln) at a depth below the
highest peak.
Replaces tp% - Bearing Ratio as defined in ISO 4287 - 1984
RPc. Peak Count
The number of local peaks which project through a selectable band
centred about the mean line or a line parallel to it. The count is
determined only over the evaluation length though the results are
given in peaks per cm (or per inch)
Known as Pc before 1997
Rsk. Skewness
Rsk is a measure of the symmetry of the profile about the mean
line.
This parameter indicates whether the spikes on the surface are
predominately negative or positive or if the profile has an even
distri- bution of peaks and valleys.
Rda. R Delta a or Rda or RDa - Arithmetical Mean Slope
Arithmetical Mean Slope of the Profile within the Sampling
Length.
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Surtronic S25
Further details are included in the Taylor Hobson booklet 'A Guide
to Surface Texture Parameters'.
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Surtronic S25
Page 1-6

Chapter 2
Description
Surtronic S25
The Surtronic 25 is a portable, self-contained instrument for the
measurement of surface texture and is suitable for use in both the
workshop and laboratory. Parameters available for surface texture
evaluation are:
• Ra, Rz, Rt, Rp, Rmr, RPc, Rv, Rz1max, Rsk, Rda
An explanation of the surface texture parameters evaluated by this
instrument is given in Chapter 1, and in the publication A Guide to
Surface Texture Parameters.
The parameter evaluations and other functions of the instrument
are microprocessor based. The measurement results are displayed
on an LCD screen and can be output to an optional printer or
computer for further evaluation.
The instrument is normally powered by an alkaline non-recharge-
able battery. If preferred, a mains adaptor can be used, (code 112/
1551 - UK, 112/1595 - Euro, B112/1594 - US).
Figure 1
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Surtronic S25
TheEquipment
The standard Surtronic 25 M112/3522-01 includes:
• 1off Traverse unit: 112/3522-01
• 1 off Standard Pickup: 112/1502
• 1 off Reference Specimen: 112/1534
• 1 off Pickup cable: 112/1257
• 1 off Screwdriver: QA 0001
• 1 off Battery: QB 0016
Note: certain items described in this handbook are optional and
may not form part of your particular system.
Traverse Unit
The top panel of the traverse unit carries a membrane type control
panel and a liquid crystal display. The unit houses the electronics
for controlling the measurement sequence, computing the
measurement data and outputting the results to the display, or to
the RS232 port for use with a printer (when included) or to a
com- puter, for further analysis.
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Battery
Surtronic S25
The unit also contains a drive motor which traverses the pickup
across the surface to be measured. The measuring stroke always
starts from the extreme outward position. At the end of the
measurement the pickup returns to this position ready for the
next measurement. The traverse length is determined from
selections of cut-off or length.
Figure 2
Pick-up Select Display
Connector Key Battery
Compartment
RS232
Connector
Measure Scroll Print
key key key
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Surtronic S25
Pick-up Mounting Components
The pick-up is fastened to the drive shaft by the following means:
Mounting Bracket. This is clamped to the drive shaft by means
of a knurled knob. Although normally used upright, as shown in
figure 3, it can be turned to angle the pick-up or to take it off the
centre line, as shown in figure 3a. It can also be mounted
sideways on the drive shaft, when the right angle pick-up is in
use.
Figure 3: pick up mounting
Pick-up Clamp Drive Shaft
Insert Extension
rod here
Connector Adjustable Mounting
Pick-up Support Bracket
Pick-up
Holder Mounting Bracket
Clamp Screw
Use this mounting position
when the right angled pick-up is used
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Surtronic S25
Figure 3a
Figure 3b
Adjustable Support. This can be clamped at any position on
the slide of the mounting bracket to provide pick-up height
adjustment.
Pick-up holder. This fits into the crutch of the pick-up support
and is held in place by a spring plunger. A biased holder, when
used as shown in figure 3, exerts a biasing force on the pick-up
(depending on which way the holder is inserted into the support
crutch). It can also be used to position the pick-up directly
underneath the display unit, as shown in figure 4.
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Surtronic S25
Figure 4
The holder will hold the pick-up at right angles to the drive shaft
when it is pivoted away from the surface (eg while changing the
work piece).
Connector. The connector of the pick-up lead is screwed into the
end of the pick-up and is then inserted into the end of the pick-up
holder, with the lead coming out through the slot in the holder.
It is advisable to connect the lead to the display-traverse unit first
and then the pick-up. To connect the pick-up to the display-
traverse unit: the pick-up has 2 threaded ends with location pins.
Insert the location pin securely into the Surtronic body and tighten
the threaded collar.
When the extension rod is used, the short pick-up lead is not
required and the end of the rod itself is inserted into the holder.
Pick-up. The pick-up is a variable inductive type transducer,
which is supported on the surface to be measured by a skid, a
curved support projecting from the underside of the pick-up in the
vicinity of the stylus. As the pick-up traverses across the surface,
Page 2-6