User Guide
FreqCalcLegal notice
1. edition© 2015 Getzner Werkstoffe GmbHContent is subject to change without notice.
All rights to this documentation, especially the right to duplication, distribution
and translation, are reserved. No part of this document may be reproduced,
processed, duplicated or distributed without the written consent of Getzner
Werkstoffe GmbH. All information provided in this user guide is correct to thebest of our knowledge and belief. Getzner Werkstoffe GmbH cannot be held
liable for damage arising from the use of this document.
Content developed by:
Getzner Werkstoffe GmbH
Herrenau 56706 Bürs, Austria
T +43-5552-201-0
F +43-5552-201-1999
info.buers@getzner.com
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Table of Contents
Legal notice ................................................................................................. 3
1.
About this document ............................................................................... 4
1.1
Layout .........................................................................................................4
1.2
What does FreqCalc do? Appropriate usage ......................................52.
Requirements and safety ........................................................................6
2.1
General safety notes ................................................................................6
2.2
Web browser recommendations ...........................................................6
2.2.1
Configuring trusted sites ..................................................................... 7
2.2.2
Configuring the pop-up blocker .........................................................8
2.3
PDF reader .................................................................................................9
2.4
User account .............................................................................................92.4.1
Creating a user account ..................................................................... 10
2.4.2
Changing your user settings and password ...................................13
2.4.3
Logging out ........................................................................................... 143.
How it works .............................................................................................. 16
4.
Starting the program.............................................................................. 17
4.1
Customising your profile ....................................................................... 18
5.
User interface ..........................................................................................20
5.1
Project area...............................................................................................21
5.2
Input area .................................................................................................22
5.3
Results area .............................................................................................24
5.4
Archive ......................................................................................................26
5.4.1
Saving a calculation ............................................................................27
5.4.2
Opening a saved calculation .............................................................27
5.4.3
Deleting a saved calculation .............................................................27
5.5
Graphs .......................................................................................................28
5.5.1
Deflection curve ...................................................................................28
5.5.2
Graph of isolation ............................................................................... 30
5.6
Table ..........................................................................................................32
5.7
Additional option for pre-stressed bearing calculation ................ 34
5.7.1
Input bushing area ............................................................................. 34
5.7.2
Bushing results area ...........................................................................36
5.7.3
Graph of pre-stressed bearing ......................................................... 38
6.
Case studies .............................................................................................40
6.1
Case study 1: Simple bearing calculation ........................................ 40
6.2
Case study 2: Pre-stressed bearing calculation ............................ 42
7.
Frequently asked questions ................................................................45
8.
Glossary .....................................................................................................46

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1. About this document
This user guide has been produced for users of the FreqCalc online calculation
program developed by Getzner Werkstoffe GmbH. Users are assumed to be
familiar with the use of the internet and to have a basic technical knowledge ofthe field.

1.1 Layout
Sidebar
The sidebar contains general safety notes on avoiding errors, particularly operating errors, together with background information on the physical principles
and important information about vibration isolation.
Symbols
This user guide explains how to use FreqCalc in the appropriate way. The following symbols are used:
WARNING

This safety note warns of the risk of serious errors in operating the program.
Operating errors can lead to serious design faults and hence to damage toinstalled machines or components. At these points always check that you haveentered your data correctly. If you need help with technical questions, consult
a trustworthy source with technical expertise or contact Getzner WerkstoffeGmbH.

CAUTION

This safety note warns of the risk of errors in operating the program that could
lead to a misinterpretation of the results or to a loss of data and indicates safety-related aspects of data management. At these points double-check the data
you have entered.

NOTE

4

This note offers tips to simplify the use of the program or provides backgroundinformation on calculating or interpreting results.

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Styles
Any data that can be entered via your computer keyboard
is printed in italics in this guide.
This data may be either text (e.g. project XY) or numbers
e.g. 12,345).

Italic

All inputs that can be made with your mouse are printed in bold in this guide.
Sequences of steps are linked by means of a > symbol.
Example: Select File>Print

Bold

This symbol indicates a required action. It instructs you to carry out an action.

>

This symbol indicates the results of an action. In order to obtain the results, youmust first carry out the preceding action.

-

Screenshots
Screenshots illustrate individual steps or results and are designed to help you
carry out the actions. The relevant areas are framed by a red line.

1.2 What does FreqCalc do?
Appropriate usage
FreqCalc is used for calculating elastic polyurethane materials from Getzner
Werkstoffe GmbH.
The calculations are based on the physical model of an SDOF oscillator witha weightless spring on a solid, smooth foundation. The calculation program
FreqCalc makes calculations based on the assumption of loading with a rigid
mass in the centre of gravity. The calculated values are relevant for the degreeof freedom in the vertical direction (1st degree of freedom), taking into consideration the non-linear behaviour of the material. The latest material data isalways applied, taking shape factor dependence into account. Calculations that
do not fall within this model cannot be performed with FreqCalc.

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2. Requirements and safety
FreqCalc is a web-based solution and operates in a web browser. All values forthe calculation are entered in an input screen. The calculation is performed on
the server. Then the results are returned to the program. FreqCalc operates
independently of any operating system. No installation on your computer isrequired. You do not need administrator rights. All you need is internet accessand a standard web browser.

2.1 General safety notes
In order to use FreqCalc, you need a basic technical understanding of the field.
Only use the program if you are able to interpret the results correctly.

2.2 Web browser recommendations
You can use any web browser, provided it supports the following functions:• Cookies• JavaScript
NOTE

Use the recommended webbrowsers to ensure error-free

Optimum results for error-free operation are obtained with the following web
browsers:

operation.

• Microsoft® Internet Explorer® Version 7 or higher - http://www.microsoft.com• Mozilla Firefox® Version 3 or higher - http://www.mozilla-europe.org

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2.2.1 Configuring trusted sites
FreqCalc operates with JavaScript. The default security level in Microsoft®
Internet Explorer® can prevent pages containing ActiveX or Script elements andplug-ins from displaying correctly. If you use Microsoft® Internet Explorer®, add
http://www.getzner.com to your list of trusted sites.
› Start Microsoft® Internet Explorer®.
› Select Tools >Internet options.
– The Internet options dialog opens.
› Select the Security.
› Select the Trusted sites zone and then click Sites.
– The Trusted sites dialog opens.
› Enter http://www.getzner.com in the input field and click Add.
– The site now appears under Websites.

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2.2.2 Configuring the pop-up blocker
FreqCalc allows you to export calculations in PDF format. The export functionuses pop-ups. If you use Microsoft® Internet Explorer® it is advisable to configure the pop-up blocker to allow pop-ups fromhttp://www.getzner.com. To configure the pop-up blocker, proceed as follows.
› Start Microsoft® Internet Explorer®.
› Select Tools>Internet options.
– The Internet options dialog opens.
› Select the Privacy› Tick the Turn on Pop-up Blocker checkbox and then click Settings.
› Enter http://www.getzner.com in the input field and click Add.
– The site now appears under Allowed sites.
– Pop-ups from this website are allowed.

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2.3 PDF reader
You can export calculations in PDF format and save them on your computer or
print them. This allows you to display the input values and calculated results inan organised fashion. In order to read or print the PDF files you need a standard
PDF reader. These are available on the internet for download from the manufacturers‘ websites and are normally free of charge.
Standard PDF readers:• Adobe® Reader®: http://www.adobe.com• Foxit® Reader: http://www.foxitsoftware.com• PDF-XChange Viewer: http://www.tracker-software.com

2.4 User account
FreqCalc can only be used if you have an active user account on the Getzner
Werkstoffe homepage. This user account gives you access to the closed website
area, with specific information about materials and products. This information
includes:• General material data
• Background information about material properties and vibration isolation• Chemical resistance of materials• Material data sheets for the Sylomer® and Sylodyn® product ranges• Product data sheets from the railway and construction sectors• FreqCalc calculation program

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92.4.1 Creating a user accountTo create a user account on the Getzner Werkstoffe homepage, proceed asfollows.
› In the address line of your web browser type the address
http://www.getzner.com.
› In the menu at the bottom left of the screen select Login.
› In the text underneath the input fields select the word >Register now.

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Registration form
NOTE

By sending us your data you
agree to your data being
stored on our server and possibly to being contacted by amember of the Getzner Werkstoffe team. We will not pass
on your data to third parties.

NOTE

Your password is sent to theserver in encrypted form.
For that reason the string ofcharacters displayed in the
input field is longer than yourpassword.

CAUTIONStore your password separately from your email address.
Choose a location which nobody else can access. Getzner
Werkstoffe will never ask you– This will take you to the registration page.
› Enter your personal details in the required fields and read the note in theright-hand column.
› Tick the checkbox to confirm that you have read the note in the right-handcolumn.
› To complete the registration process click Submit.

FreqCalc User Guidefor your user details over the
telephone or by email. If you
receive a suspicious email, do
not reply to it. Instead please
notify us immediately by calling us on +43-5552-201-0.

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NOTE

It can take up to 24 hours
to process an application.
Getzner Werkstoffe reserves
the right to deny access to thecalculation program.

12– You will shortly receive an email sent to your nominated email address.
› Click on the confirmation link in the email to confirm your registration.
– This will take you to the Getzner Werkstoffe homepage.
– Three selection fields appear in the web browser: FreqCalc, Typematch andTimberCalc› Before you can use the FreqCalc or TimberCalc programs, you will need torequest authorisation by clicking Request authorisation– Once your request has been verified, you will receive an email confirming
successful activation and containing a link to the relevant calculation program(FreqCalc or TimberCalc).
› You only need to activate the program once. You can now access the desired
calculation program via the login field on the Getzner Website.
› You can use the Typematch program without requesting authorisation byclicking on >Open Typematch.

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2.4.2 Changing your user settings and password
You can change your details in the closed user area at any time.
› In the address line of your web browser type the address
http://www.getzner.com.
› In the menu at the top right of the screen select >Login.
› In the Login screen enter your email address and your password.
› Click >Login.
– This takes you to the closed user area.
– The user symbol is displayed with your name at the top right.
› Move the cursor over the user symbol and click >Change userdata.

› Enter any changes in the corresponding input field and confirm by clicking> Submit.
– The text will confirm that your details have been updated.

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2.4.3 Logging out
You can leave the closed user area at any time.
› Move the cursor over the user symbol and select >Logout.
– You will be logged out and returned to the login screen.

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You can reset your password at any time.
› In the address line of your web browser type the address› http://www.getzner.com.
› In the menu at the top right of the screen select Login.
› Select >Forgot your password? under the password input field.
– Type your email address in the input field and click>Reset password.
– You will shortly receive a new password sent to your nominatedemail address.

FreqCalc User Guide – Translation from original language

NOTE

Remember to change yourpassword again once it has
been reset.

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3. How it works
FreqCalc is an online solution. This means that you do not have to install the
program on your computer in order to use it. So no program data or materialvalues are stored on your computer, and the program does not access yourcomputer to perform a calculation.
All the input values needed for a calculation are entered in an input screen (theuser interface). There are a number of different functions and input options.
Once you have finished entering your data, clicking the Calculation button in
the user interface sends all values to the Getzner Werkstoffe server. The calculation is then performed on the server. The results are returned to the userinterface and displayed as numerical values and graphs.
All connections are encrypted and ensure the highest security standards.

Getzner Werkstoffe
SERVER

USER

Input values
Encrypted connection
Results +GraphsUser interface

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4. Starting FreqCalc
The first time you start the calculation program you will see the conditions forusing FreqCalc. Read them through carefully and accept them. You can also
download and store the conditions for use in PDF format. To start the program,proceed as follows.

NOTE

You can also download andstore the conditions for use in› Log in to the closed user area on the Getzner Werkstoffe website.
› Select Open FreqCalc on the overview screen for the different calculation
programs.
– The conditions for use will appear.
› Read through the conditions for use carefully.
› Tick the I accept the conditions
checkbox and then click >Continue to FreqCalc.
– The FreqCalc calculation program starts.

PDF format. To do so, under
the conditions for use select>Download as PDF.

If you do not want the conditions for use to be displayedeach time you open the
program, tick>Don‘t ask me again.

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4.1 Customising your profile
You can personalise your settings and user data at any time.
To do so, proceed as follows.
NOTE

The Getzner Werkstoffe logo
is included as standard in PDF
exports. You can customise
your PDF exports if you wish,by adding your company logo
for example. If you do not want
to include a customised logo,
leave this box empty.

Make sure that your logo
complies with the following
criteria:
File format: JPG / GIF / PNG
File size: max. 500 kB
Aspect ratio: 7:3

18› Move the cursor over the user symbol and select >Change userdata.
– The settings dialogue opens.
› Enter the corresponding details into the required fields.
› Logo: If you would like to customise your PDF exports to include a logo (e. g.
company logo) click >Browse under the Logo menu item and select the appropriate logo from your data file structure.
› Click Open.
– The path to your logo on your computer appears in the input field.
› Choose the language in the dropdown menu. The following languages› are available:• German• English• French• Spanish• Danish• Italian• Polish• Russian• Czech› Choose your preferred number format in the dropdown menu.
› If desired, you can select the Anglo-American system for your calculation.
› Address: If you want to customise your PDF exports to show your address,
enter the details in the Default address for FreqCalc projects input field.
› To apply these settings, click >Submit– The text will confirm that your details have been updated.
› To return to the FreqCalc user interface, select >Dashboard and >Open
FreqCalc via the selection window.

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5. User interface

Project area
Input area
(Input main bearing)Calculation of prestressed bearing | Input
bushing

Results area
(Bushing results)
Results area
(Main bearing results)
GraphsDeflection curve andgraph of isolation
Table
Graph of pre-stressedbearing

Downloadbuttons
Basis ofcalculation

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5.1 Project area

Project:
Input field for the nameof your project.

Remark:Input field for additionalcomments about the
project.

Author:Shows the name underwhich you registered.

FreqCalc User Guide – Translation from original language

Address:
Ticking the checkbox
loads the specified
address. You can also
enter an alternative
address in the input
field.

NOTE

If you do not want an address
to be included in the printed
output, leave this field blank.

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5.2 Input area
NOTE

If you ticked the checkbox forthe pre-stressed bearing calculation function, the title changes to „Input main bearing“.

Material:
Dropdown menu for selecting different productranges. The productranges available to you
will depend on your user
rights.
Quantity:
Defines the number ofbearings used.

Shape:
Dropdown menu for selecting a bearing shape.
The following shapes areavailable:Rectangle andCylinder.

Holes:
Checkbox to activate
the Holes function. The
centre point of a hole isaligned centrically withthe bearing.

Length:[Condition: Shape =Rectangle]: Defines thelength of your bearing.

Quantity:[Condition: Holescheckbox ticked]: Defines thenumber of holes in the
bearing.

NOTE

The specified thicknesses are
standard material production
thicknesses. Custom thicknesses may give rise to additional production costs, with
implications for delivery timeand price.

CAUTION

Units
Disregarding the units canhave serious consequences forthe calculation. Always checkthe unit when you enter theload value.

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Thickness:
Dropdown menu for
selecting a standard
material thickness. You
can also enter a custom
material thickness inthe field.

Load type:
Dropdown menu for
selecting the load type.
The available load types
are Load, Mass andForce. The input field
determines the value ofthe specified load.

Width:[Condition: Shape =Rectangle]: Defines thewidth of your bearing.
Diameter:[Condition: Shape = Cylinder]: Defines the diameter of your bearing.

Diameter:[Condition: Holes
checkbox ticked]: Defines the diameter ofthe holes.

Secant:Checkbox to activate
the Secant stiffness
function. The input fields
determine the lower andhigher limits.

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Reset button: Restoresthe input fields anddropdown boxes to their
original status.

Save button: Saves thecurrent calculation under the specified project
name.

FreqCalc User Guidefor download
Conditions for use
for download

Calculation button:
Starts the calculation
using your specified
values.

Archive button:
Opens the calculationarchive, in which up toten calculations can be
stored.

FreqCalc User Guide – Translation from original language

Load saved address:
If the box is checked,
the program automatically uses the address
specified during customisation (see 4.1). If thebox is not checked, an
individual project address can be entered.

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5.3 Results area

Choose material:
Shows the material calculated on the basis of yourinputs. Use the orange arrows to the left and rightof the dropdown menu to select the next softest or
stiffest material. The results are refreshed each time
you change the material type.
If a material is the best one based on your inputs,
the word „Best“ is displayed below the dropdown
menu, against a green background.

NOTE

Cellular materials such as
Sylomer® SR 11, SR 18 andSR 28 are volume-compressible, so the influence of shape

Shape factor:
The shape factor is a geometric measure of the
shape of an elastomer bearing and is defined as
the quotient of the surface area under load and thecurved surface area of the bearing. The deflection
curve for elastomers is dependent on the shape factor (already taken into account in the calculation).

factor on stiffness can bedisregarded. As the elastomer
compactness increases, howev-

Surface:
The surface area under load of the (main) bearing.

er, the shape factor becomesincreasingly important.

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Static load limit:
Indicates the value up to which the material can beused under a permanent static load. This value isdependent on the shape factor.

CAUTION

Different load values
The values for dynamic loads

Capacity:
The capacity of the material under the specified
load.

or peak loads are different fromthose for static loads. Pleaserefer to the individual productdata sheets for exact values.

Deflection:
Distance by which the material is compressed when
the specified load is applied.
Natural frequency:
Lowest vertical natural frequency of the elasticallysupported system. The lower the natural frequency,
the higher the vibration isolation.

WARNING

Overload
The calculated material overload is given as a percentage.

Dynamic bedding modulus:
Ratio of the dynamic stiffness to the surface area
under load. This is also known as stiffness per unit
area.

The field is shown with a
red background. Check yourinputs and choose the next
highest material type from thedropdown menu. In case of
doubt please contact Getzner
Werkstoffe.

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Dyn. modulus of elasticity:
The result shows the dynamic modulus of elasticity
under the specified load for the defined material
type.
Secant stiffness:
This result is only displayed if the Secant checkbox
is ticked in the Input (or Input main bearing) area
and the lower and upper limits have been entered.
Secant stiffness is an additional value that is not
absolutely necessary for a load rating. Experience
shows that this value is mainly used in the railway
sector.

5.4 Archive
The archive can be used for storing, opening and deleting calculations.

Project: Shows the name under which the calculation was saved.
Date: Shows when the calculation was saved.
Open button: Inserts the stored values in the input fields in the user interface.
Delete button: Deletes the stored calculation from the archive.
X: Closes the Archive dialog.

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5.4.1 Saving a calculation
You can save calculations in the archive. To do so, proceed as follows.
› Enter your details in the input fields.
› Click the Save button.
– The calculation is saved in the archive under the specified project name.

NOTE

You can store up to ten calculations in the archive.

5.4.2 Opening a saved calculation
To open a saved calculation from the archive, proceed as follows.
› Click the Archive button.
– The Archive dialog opens. The saved calculations are listed as a table in dateorder. Each record shows the project name, date and time.
› Next to the record you wish to open, click the Open button.
– The input values are inserted in the input fields.

5.4.3 Deleting a saved calculation
To delete a saved calculation from the archive, proceed as follows.
› Click the Archive button.
– The Archive dialog opens. The saved calculations are listed as a table in dateorder. Each record shows the project name, date and time.
› Next to the record you wish to delete, click the Delete button.
– The record is deleted from the archive.
› To close the Archive dialog, click X.

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5.5 Graphs
5.5.1 Deflection curve
The deflection curve (1) maps the relation between load and deflection for thematerial type. The horizontal blue line (2) shows the static load limit for the selected material type. The horizontal green line (3) shows the specified load. The
area below is shown in green. A material overload occurs at the point at which
the specified load exceeds the static load limit. An overload is indicated in thechart by a red line (5). The area below is shown in red.
If a secant is specified, this is shown as a straight orange line (4) from the defined lower limit to the defined upper limit.

(3)

(1)

(4)

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(5)

(2)

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Expanding areas of the deflection curve
You can expand the view of areas of the deflection curve. To do so, proceed asfollows.
› Move your mouse pointer over the chart.
– The mouse pointer turns into a cross.
› Position the centre point of the cross at the top left corner of the area
you wish to expand.
› Hold down the left mouse button and drag the centre point of the crossto the bottom right corner of the area you wish to expand.
› Release the left mouse button.
– An expanded view of the selected area is displayed.

Alternative: Centred zoom
You can expand or reduce the size of the chart view using the zoom icons on
the right-hand edge of the chart.
› To zoom in, select› To zoom out, select› To restore the chart to its original size, selectFreqCalc User Guide – Translation from original language

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5.5.2 Graph of isolation
The isolation curve maps the relation between isolation (in dB) and frequency(in Hz) of the vibrating system. The calculated natural frequency is located at
the highest point of the curve (1). The vibrating system is at resonant frequency
here. At the point of natural frequency x√2 the isolation curve intersects withthe horizontal zero line (2). Up to this point an elastic mounting intensifies thevibration rather than improving it (area shown in red). Beyond this point ofintersection vibration isolation is effective. The greater the difference between
the excitation frequency and the natural frequency of the system, the more
effective the vibration isolation (degree of isolation).

(1)
(2)

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Expanding areas of the graph of isolation
You can expand the view of areas of the graph of isolation. To do so, proceed asfollows.
› Move your mouse pointer over the chart.
– The mouse pointer turns into a cross.
› Position the centre point of the cross at the top left corner of the area you
wish to expand.
› Hold down the left mouse button and drag the centre point of the cross tothe bottom right corner of the area you wish to expand.
› Release the left mouse button.
– An expanded view of the selected area is displayed.

Alternative: Centred zoom
You can expand or reduce the size of the chart view using the zoom icons on
the right-hand edge of the chart.
› To zoom in, select› To zoom out, select› To restore the chart to its original size, selectFreqCalc User Guide – Translation from original language

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5.6 Table

NOTE

In vibration isolation the de-

The table under the graph of isolation shows the frequency spectrum, isolation and degree of isolation for the calculation. A negative degree of isolation
denotes a worsening of the situation, a positive degree of isolation an improvement.

gree of isolation characterises
the isolation effect as the ratio
between the input and output
forces or the input and output

Example:At an excitation frequency of 40 Hz the system isolation is-15.8 dB. This corresponds to a degree of isolation of +84%.

amplitudes.

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Download buttons:

Language selection:
Dropdown menu for choosing the language in which the calculations are to be
downloaded. This allows you to create a PDF of the calculation in a different
language from the input language.

NOTE

In the case of a pre-stressedbearing calculation the data-

Calculation button:
Creates a PDF file of the entire calculation and starts the download process. The
file includes the Project, Input and Results areas and the basis of calculation.

sheet relates to the main
bearing.

Product datasheet button:
Starts downloading the calculated product datasheet.

Basis of calculation:

The basis of calculation describes the exact assumptions on which the FreqCalc
calculation is based (see also Appropriate usage). It also includes the date on
which the material data was last updated and the software version number.

CAUTION

Material data
The date on which the material
data was last updated mayvary depending on the material type. Users are not notified
if the material data is changed.
Check the date of the material
data at regular intervals, especially if you have saved calculations in the archive. Changes
to the material data may cause
the calculation results to vary.

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5.7 Additional option for pre-stressed bearing calculation
Schematic diagram of a pre-stressed bearing:
Bolt
Preload element
Bushing
Machine baseMain bearing
Foundation

5.7.1 Input bushing area

Calculation of pre-stressed bearing | Input bushing:
Checkbox to activate the pre-stressed bearing calculation
function and the input fields for bushings.

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Material:
Dropdown menu for selecting a material type.
The material types available to you will dependon your user rights.

Shape:
Dropdown menu for selecting a bearing shape.
The following shapes areavailable:Rectangle andCylinder.

Bushings per main
bearing:
Defines the numberof bushings per main
bearing.

Length:[Condition: Shape =Rectangle]: Defines thelength of your bearing

Thickness:
Dropdown menu for
selecting a standard
material thickness. You
can also enter a custom
material thickness in thefield.

Holes per bushing:
Checkbox to activate theHoles function.

NOTE

Owing to the differing loads,

Quantity:[Condition: Holes per
bushing checkbox
ticked]: Defines thenumber of holes in thebushing.

Width:[Condition: Shape =Rectangle]: Defines thewidth of your bearing

Diameter:[Condition: Holes per
bushing checkbox
ticked]: Defines the diameter of the holes.

Diameter:[Condition: Shape =Cylinder]: Defines thediameter of your bearing

Deflection underpreload:Defines the desired deflection under preload.

the material type used for thebushing is not dependent on
the material type used for themain bearing. The choice ofmaterial type is governed by
the required preload force.

NOTE

The specified thicknesses are
standard material production thicknesses. Custom
thicknesses may give rise to
additional production costs,
with implications for delivery
time and price.

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5.7.2 Bushing results area

WARNING

Overload
The calculated material over-

Shape factor:
The shape factor is a geometric measure of the
shape of an elastomer bearing and is defined as
the quotient of the surface area under load and thecurved surface area of the bearing.

load is given as a percentage.
The field is shown with a
red background. Check yourinputs and choose the next

Surface (*):
The surface area under load of the pre-stressedbearing.

highest material type from thedropdown menu. In case of
doubt please contact Getzner
Werkstoffe.

Load of bushing:Calculated from the preload force and thesurface area.
Capacity:
The material capacity with the calculated
preload force.

NOTE

The necessary preload force

Preload force (*):
The force acting on the bushing.

is determined by the specificinstallation situation. In case of
doubt please contact Getzner
Werkstoffe.

Dyn. Stiffness (*):
Determined from the selected material and thecalculated preload.
(*) refers to all bushings per main bearing.

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Additional results in the main bearing area

Additional load on main bearing:
Additional load acting on the main bearing if a bushing is used.
Total load:
Sum of the additional load on the main bearing andthe load.

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5.7.3 Graph of pre-stressed bearing
This graph only appears if the Calculation of pre-stressed bearing checkbox is
activated.
The graph shows the deflection curve for the main bearing (1) and bushing(2). The purple line (3) indicates the load on the main bearing as a force. The
turquoise line (4) represents the preload force arising from the deflection underpreload.

(1)

(3)

(4)

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(2)

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Expanding areas of the pre-stressed bearing graph
You can expand the view of areas of the pre-stressed bearing graph. To do so,proceed as follows.
› Move your mouse pointer over the chart.
– The mouse pointer turns into a cross.
› Position the centre point of the cross at the top left corner of the area you
wish to expand.
› Hold down the left mouse button and drag the centre point of the cross tothe bottom right corner of the area you wish to expand.
› Release the left mouse button.
– An expanded view of the selected area is displayed.

Alternative: Centred zoom
You can expand or reduce the size of the chart view using the zoom icons on
the right-hand edge of the chart.
› To zoom in, select› To zoom out, select› To restore the chart to its original size, selectFreqCalc User Guide – Translation from original language

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6. Case studies
6.1 Case study 1: Simple bearing calculation
Scenario:
A machine with a dead weight of 9 tonnes is to be elastically supported. The
machine stands on four feet, each with a bearing surface of 250 x 250 mm. The
disruptive vibrations start at an excitation frequency of 50 Hz. Isolation of atleast -15 dB is required.
Step 1: Enter data
› In the Quantity field in the Input area enter 4.
› In the Length and Breadth fields enter 250.
› In the Load type dropdown menu select Mass and in the input field enter
9000.
› Click the Calculation button.

Step 2: Results– Sylomer® SR 450 was calculated to be the best material.
– The material capacity is 81%.
– The natural frequency was calculated at 11,8 Hz.
– The graph of isolation shows the degree of isolation at an excitation
frequency of 50 Hz.
– The table indicates an isolation of -24,2 dB at an excitation frequency of
50 Hz. The degree of isolation is 94%.
This satisfies the minimum required value.

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6.2 Case study 2: Pre-stressed bearing calculation

NOTE

Lifting force
This causes the structure
to „lift“ in the support area
unless it is anchored down or acorresponding load is applied

Scenario:
A machine with a dead weight of 9 tonnes is to be elastically supported. The
machine stands on four feet, each with a bearing surface of 250 x 250 mm.
The disruptive vibrations start at an excitation frequency of 50 Hz. An isolation
value of at least -15 dB is required.
Owing to a lifting force of 3 kN, the machine must be anchored to the foundation. This is to be achieved by means of one preload element
per machine foot (120 x 70 mm) and two bolts (M20).

in the support area.

Step 1 – Step 2: Use values from case study 1
Holes
An M20 bolt has a diameter of
20 mm. To make it easier topass the bolt through the holeon assembly, it is advisable forthe hole to be larger than thebolt. In this case an empiricalvalue of +2 mm is chosen.

Step 3: Enter bushing data
› Tick the Calculation of pre-stressed bearing | Input bushing› In the Thickness dropdown menu select 12,5.
› In the Length field enter 120 and in the Width field enter 70.
› Tick the Holes per bushing› In the Quantity field enter 2.
› In the Diameter field enter 22.
› In the Deflection under preload field enter 1.

Step 4: Adjust the main bearing input› In the Input main bearing area tick the Holes per pre-stressed element› In the Quantity field enter 2.
› In the Diameter field enter 22.
› Click the Calculation button.

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Step 5: Main bearing results– The natural frequency has changed and is now 11,7 Hz.
– The capacity is 91%.
Step 6: Bushing results– The bushing capacity is 72 %.
– The preload force was calculated at 2,15 kN. Given the lifting force of 3 kN,
the preload force is too low.

Step 7: Adjust the bushing input› In the Material area select the next stiffest material, in this case
Sylomer® SR 850.
› Alternative 1: Enter a different value in the Deflection under preload field.
› Alternative 2: Adjust the bushing dimensions.
› Click the Calculation button.

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Step 8: Results– The main bearing capacity is 98%.
– The natural frequency was calculated at 12.0 Hz.
– The bushing capacity is 77%.
– The preload force was calculated at 3.85 kN. This is high enough to counteract
the lifting force.
– The graph of isolation shows the isolation effect at a disruptive frequency of
50 Hz.
– The table indicates an isolation of -24.0 dB at an excitation frequency of
50 Hz. The degree of isolation is 94%.
– This satisfies the minimum required value.
– The pre-stressed bearing graph shows the deflection curves for the main
bearing and bushing. The purple line represents the dead weight of themachine as a force. The turquoise line represents the preload force.

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7. Frequently asked questions
Is there an offline version of FreqCalc?
No. FreqCalc is only available online via the Getzner Werkstoffe homepage.
Do I have to register in order to use FreqCalc?
Yes. You need to set up a user account on the Getzner Werkstoffe homepage inorder to use FreqCalc.
I have registered for FreqCalc but I still can‘t use FreqCalc. Why not?
The registration process may not be complete yet.
Is FreqCalc available in other languages too?
Yes. FreqCalc is available in German, English, French, Spanish and Danish. Other
language versions are being developed.
Do I need to change the program language in order to print out a PDF file inanother language?
No. In the footer of the Results area you can choose the download language.
Will I be notified of changes to the material data?
No. You will not be notified. The current date of the material data appears inthe basis of calculation in the footer of the calculation program and of the PDF
exports.
I have added a logo to customise my user profile. Why does the logo lookdistorted?
Check that the aspect ratio is correct. Your logo must have an aspect ratio of
7:3.
How many calculations can I store in the archive?
You can store up to ten calculations in the archive. To store new calculations,delete those that you no longer need.
I‘ve forgotten my password! How can I request a new one?
Please refer to Resetting a password.
FreqCalc does not display correctly!
Check which version of your web browser you are using and update it if necessary. If you still experience problems, please contact online support. Email:onlinesupport.buers@getzner.com

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8. Glossary
Natural frequency
Frequency at which an oscillating system oscillates
freely after a single excitation; the attenuation timeis dependent on the isolation.
Vibration isolation
Reduction in the transfer of mechanical vibrations
by the installation of elastic intermediate components; a distinction should be made between reducing the transfer of vibrations from a vibration exciter to the environment (emission control, isolationof the exciter) and shielding an object against theeffects of vibration from the environment (environmental control, shielding of an object).
Polyurethane
Abbreviation PUR or PU; polyurethanes are prepared by the polyaddition of isocyanates andpolyalcohols and can range from cellular through tocompact structures. A distinction should be madebetween polyether urethanes and polyester urethanes.

Degree of isolation
In vibration isolation characterises
the isolation effect as the ratio
between the input andoutput forces or the input andoutput amplitudes.
Pre-stressed bearing
A pre-stressed bearing is a bearing designed toprevent transmission of structure-borne noise inmountings. Each pre-stressed bearing consists of amain bearing and a bushing.

Additional terms can be found in the Getzner
Werkstoffe glossary at http://www.getzner.com
Downloads>Brochures>Glossary

Single degree-of-freedom (SDOF) oscillator
Vibration isolation applications are often idealisedon the basis of an oscillating system with a single
degree of freedom, consisting of a mass and aspring.
Deflection curve
Describes the relation between load and deflection
in graphical form; depending on the rate of loading
it may be a quasi-static or a dynamic deflection
curve.

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