Rev 2008-03-20 SCM Welcome to the Bearing Selection Guide v.3.0 The ultimate calculation tool

rev 2008-03-20 SCM

Welcome to the Bearing Selection Guide v.3.0Welcome to the Bearing Selection Guide v.3.0

The ultimate calculation toolThe ultimate calculation tool

2 Bearing Selection Guide v.3.0

● The Timken Bearing Selection Guide Version 3.0 (“TBSG3”) is program that is installed on your Microsoft Windows PC to provide bearing information and calculations for your applications.

● This tool was designed to provide you with reliable methods of choosing and using appropriate Timken bearings for your bearing applications.

● The program will also enable you to build a model of your bearing application. This application model can then be used to analyze your application, evaluate bearing selections and can be sent to your local Timken Sales Engineer for further analysis.

● This Training is intended to supply you with technical information and step-by-step instructions on how to properly use the Bearing Selection Guide.

● It will also provide you with a step-by-step example on how to create a bearing application to model your bearing system.

1. Introduction1. Introduction


Running the Timken Bearing Selection Guide To run the Timken Bearing Selection Guide, follow one of these

procedures:

• Double-click on the icon installed on the Windows desktop.

• From the Windows Start menu, select Programs / The Timken Company / Timken Bearing Selection Guide v3.0 / TBSGv3.0

Exiting the Timken Bearing Selection Guide To exit the Timken Bearing Selection Guide, select Quit from the Files

menu on the main screen.




The Timken Bearing Selection Guide (TBSG) will open to the main startup screen. If this copy of the Timken Bearing Selection Guide has not been registered, a Registration Code and a link to the TBSG on–line Internet registration page will be shown at the bottom of this screen. Ten uses (starts) of the program are allowed without a password before service is denied.

Register NowClick here to register online. The Registration Code and some basic user information is requested. A password will be sent to the e-mail address provided at registration.


Resizing Individual Panes In many cases, the allocation of space can be changed among various features that are being simultaneously displayed. Click and drag the border between sections of the main screen to resize the panes.



Help buttonOpens the user manual.

System Units buttonAllow the user to set input and output data units as the Metric (millimetre) or Imperial (inch) unit system

2. Configuring the TBSG2. Configuring the TBSG

Global Bearing Search buttonThe global bearing search function lets user select bearing part numbers meeting specified criteria across multiple bearing types.

Units Conversion Tool button Converts commonly used measures between Metric and Imperial unit systems.


2. Configuring the TBSG2. Configuring the TBSG“Bearings” menuBearings scroll down list allows you to select a bearing type.

“Quit”Exit the Timken Bearing Selection Guide

“Applications”Allow user to model a bearing application, calculate load and life results, and select bearing to meet dimension and life requirements. Also contains a function to display ISO standard tolerances for bearing seat diameters.

“Reference tables”Shows properties of Materials and Lubricants used by the program. Also allows the user to define custom Materials and Lubricants. It also contains an Internet link to the on–line Timken Products Catalogue page.


Setting the Language Enables user to select the language used within the Timken Bearing Selection Guide.


Global Bearing SearchThe Global Bearing Search feature permits the user to select bearing part numbers meeting specified criteria across multiple bearing types

Unit ConverterThis permits the user to convert a number of quantities between Metric and Imperial unit systems.

User PreferencesTo change preferences on the local computer, select User Preferences from the Utilities menu on the main screen.



Conversion ToolSelect the category of units to convert from the tabs at the top of the window, then type the number to convert in the appropriate box. A unit conversion to the other system will be done automatically.



The following languages are available: English Français (French) Deutsch (German) Español (Spanish) Italiano (Italian) (Simplified Chinese)

Click on the Utilities menu on the main screen, then click on the Languages sub-menu to see a list of options. Choose the language you prefer by clicking on its entry from the list of options


User PreferencesTo change preferences on the local computer, enter the following

information:• User Name - Your name• Company - Your company or organization• Language Preference - The default language you prefer to see when using

the Timken Bearing Selection Guide.• Unit System - The default unit system you prefer to use when analyzing

bearings



About…This menu item opens a window to show version information about the Timken Bearing Selection Guide installed on the computer. It also shows an important message concerning the use of this software.



3. Overview of the TBSG3. Overview of the TBSG

Click the "down" arrow ( ) to expand any of these selections further. If the list becomes too long, a scroll bar will appear to permit review of the entire list, or the expanded selections can be collapsed using the "up" arrow ( ).

Click

here

“Single Row”, “Double Row”, and “Thrust Bearings” listsSelecting a bearing type permits the user to view a list of bearings of that type.

From this list, selection criteria can be applied and performance predictions can be calculated.



Bearing application This feature provide the ability to create a bearing application model utilizing several bearings and calculate bearing loads and lives for more than one bearing.

Calculations for a single bearing use the functions listed in the bearing types sections.

ISO Tolerances This feature provides values of selected ISO tolerances and fits for given shaft and hole dimensions.





Reference TablesShows properties of Materials and Lubricants used by the program. Also allows the user to define custom Materials and Lubricants.

It also contains an Internet link to the on–line Timken Products Catalogue page.



Material Table – shows material properties used and also permits the user to define specific material properties that can be used for shaft and housing calculations.



Custom Material Definition

Add a new record

Material Name - This should be descriptive, to help the user identify the material elsewhere in the program.

Young's Modulus - Sometimes referred to as the Modulus of Elasticity, this value can be entered in the current input units selected on the main screen of the Timken Bearing Selection Guide. Although not editable, the corresponding value in the other units system is calculated and displayed for reference.

Poisson's Ratio - This value has no units, and therefore is only shown once (rather than once in each unit system).

Comments (optional) - These are available to enter more details than are reasonable to include in the Material Name.



Move to the first material in the current list.

Move to the previous material in the current list.

Move to the last material in the current list.

Move to the next material in the current list.

User-defined materials are differentiated from the default materials by a check in the "Updatable" column. Only user-defined materials are editable from within the Timken Bearing Selection Guide.



Add a new record - This permits the user to define a new material and add it to the list.

Delete selected record - This will ask for confirmation before removing the currently-selected material from the list. It is only valid for user-defined materials.

Edit selected record - This permits the user to modify any of the characteristics of the currently-selected material, including the name, material properties, and comments



Lubricant Table – shows available lubricant properties and also permits the user to define specific lubricant properties that can be used in other Timken Bearing Selection Guide components.

User-defined lubricants are differentiated from the default lubricants by a check in the "Updatable" column. Only user-defined lubricants are editable from the Timken Bearing Selection Guide.


Custom Lubricant Definition

Add a new record

Lubricant Name - This should be descriptive, to help the user identify the lubricant elsewhere in the program.

Viscosity (2 entries) - These are the viscosities of the lubricant at the two specified temperatures. Although not editable, corresponding viscosities in the other units system are calculated and displayed for reference.

Comments (optional) - These are available to enter more details than are reasonable to include in the Lubricant Name.




TBSG III Home - link to the Timken Bearing Selection Guide 3 Home Page on the Timken.com internet web site.

Timken Catalog, which provides a link to the on-line TimkenProducts Catalog page on the Timken.com internet web site.



•Selecting any of these bearing types permits the user to view a list of bearings of that type.

•From this list, selection criteria can be applied and performance predictions can be calculated. Depending on the bearing type, additional options may be available.

DrawingCan be exported (to a .DXF or .PDF file), copied to the clipboard, or printed.

Information windowGives a comprehensive description of the values appearing on the drawing.

List of dimensionswhich also contains search (filter) and sort functions

Function tabs Show calculation functions that are available for this bearing type.


3. Overview of the TBSG3. Overview of the TBSGFilter function

Sort function

Filtering options include the following:To filter for parts containing a specific value in a particular column, choose that

value from the lower part of the list.To remove any existing filter for this column only, select (All).To define more complex filter criteria, such as a range or partial match, select

(Custom). To find part numbers where a value is missing in a particular column, select

(Blanks). Similarly, select (Non blanks) to find part numbers where a value is present in that column.



To send a printout of data from one page of an Individual Bearing Calculations function (or all of those functions available for the selected bearing) to a printer, click on the Print button

Print Current Page allows the user to export results from the active Individual Bearing Calculation function. Note that the List function shows details of the currently-selected bearing, not the entire list of parts.

Print All Pages allows the user to export results from all available Individual Bearing Calculation functions for the currently-selected bearing.


AutoScaleBy default, the Timken Bearing Selection Guide will resize the drawing to an integral scale in an effort to show the bearing as large as possible on the printed page, while still preserving the scaled dimensions. This scale is shown in the Drawing Scale box.

Custom ScaleTo manually change the scale of the drawing, select a different scale from the Drawing Scale drop-down box. Depending on the size of bearing, certain scales may not be applicable (causing the drawing to be unreasonably small, or to exceed the size of the printed page).



3. Overview of the TBSG3. Overview of the TBSGShow Dimensions This will add nominal values for primary envelope dimensions to the drawing. This cannot be selected at the same time as Show Symbols, so selecting one will de-select the other.

Show SymbolsThis will add primary envelopedimensions to the drawing. Each dimension will be labelled with a symbolThis cannot be selected at the same time as Show Dimensions, so selecting one will de-select the other.

Show Frame This will add a Timken frame to the drawing, which adds not only the bearing part number in the title block, but also lists specific bearing characteristics in the lower left of the drawing.

Print Bearing Tolerances Available only when Show Frame is selected, this will add "standard" tolerances for bearing envelope dimensions to the drawing when printed. Note that these "standard" tolerances apply to a basic class of the bearing, and are not representative of other bearingclasses or special product.



Hatching This will replace the solid color of the bearing rings with hatching (parallel lines).

Bearing Section Color This permits the user to select a solid color to fill the bearing rings in the drawing. Changing the color of the bearing section will de-select the Hatching option.

Output Once the drawing is formatted appropriately, it can be exported in one of four formats.


PrinterThis allows the user to print the drawing out on paper.

.DXF File This exports the basic bearing geometry (without any frame or dimensions) to a .DXF file, which can be used by many CAD programs to insert the bearing into an application drawing.

ClipboardThis copies the drawing, complete with selected features, as a picture to the Windows clipboard.

Adobe® PDF DocumentThis exports the drawing to an Adobe® PDF Document.Note that the internal geometry of the bearing is not exact. This data is proprietary to the Timken Company, but is shown to approximate values to help the user with bearing sizing and system layout.




Interactive ZoomTo zoom in on the drawing (increase the size being displayed without changing the scale), double-click on the drawing with the left mouse button. To zoom out on the drawing (reducing the displayed size), double-click on the drawing with the right mouse button.

Selective ZoomTo quickly resize the drawing (but not the scale) to a specific value, select an option from the Zoom drop-down menu. The Whole Page and Page Width options will scale the drawing to fit the available space on the screen (either in both directions or only in the horizontal direction). The percentage options define a specific zoom level.

Move / PanIf the zoom level is high enough that the entire drawing is not visible, click on the drawing and drag the mouse to view different parts of the drawing.


Global Bearing Search menuThe Global Bearing Search button permits the user to select bearing part numbers meeting specified criteria across multiple bearing types.




Once the target bearing types are selected, click the Next >> button to go to theParameters screen.

Select Bearing TypeThis option operates identically to the Global Search option, except that allbearing types are initially de-selected, allowing the user to select the target types.

Global SearchAll of the bearing types in the list are selected by default.Un-check any bearing types that should be excluded from the search.



Global search Part Number containsEnter an alphanumeric string to search for within a part number. The search is not case-sensitive. In addition, some part numbers contain hyphens, which are ignored in the search string. Leave this field blank to not constrain the search by part number.



Global search Bore [Min and Max] Enter the target range of bore dimensions in theactive unit system. Leave any value as zero (0) to ignore that constraint. So, a search with "Bore (Min) = 200" and "Bore (Max) = 0" in metric units will return bearings with a bore dimension of 200 millimetres or greater. Leave both values as zero (0) to not constrain the results by bore.

Outside Diameter [Min and Max] Enter the target range of Outer Diameter dimensions in the active unit system, similar to the bore constraint. Leave both values as zero (0) to not constrain the results by outer diameter.

Bearing Overall Width [Min and Max] Enter the target range of Overall Width dimensions in the active unit system, similar to the Bore constraint.Leave both values as zero (0) to not constrain the results by width.



Global search Dynamic Rating (C1) [Min and Max] Enter the target range of Bearing Rating (dynamic "load" capacity) in the active unit system. Leave both values as zero (0) to not constrain the results by rating. Note that the C1 rating (based on 1 million revolutions) is used for all selections, which should not be confused with the C90 rating (based on 90 million revolutions), which is sometimes used for Tapered Roller Bearings. To convert between the two, use the equation C1 = 3.86 x C90 for Timken Tapered Roller Bearings.

Note: To make changes in the list of selected bearing types, click the << Previousbutton. When finished, click the Next >> button to go to the Results screen.



Results screen Results are grouped by bearing type, as shown by the icons to the right of the screen. Click on a bearing type at the right of the screen to view the list of results for that bearing type (some may have no results).

Bearing list Click on the up and down arrows at the bottom of the list to scroll through other bearing types if not all are listed.



Select an Existing QueryWhen one or more custom queries are saved, the user can choose the Select an Existing Query option to quickly access a previous set of constraints. Both the list of bearing types and the selection criteria are saved.



Select a QueryChoose the name of the query from the drop-down box. This will restore the bearing type choices for that query, allowing the user to make any changes before clicking the Next >> button. On the Parameters screen, any predefined selection criteria for this query are also filled in, again allowing the user make any changes before clicking the Next >> button and viewing the results.


Manage Queries buttonAllows the user to view a list of saved queries.To change the name of a custom query, select it from the list by left-clicking on it, and click the Edit button. To remove a custom query from the list, select it from the list by left-clicking on it, and click the Delete button.



To change the name of a custom query, select it from the list by left-clicking on it, and click the Edit button.



To remove a custom query from the list, select it from the list by left-clicking on it, and click the Delete button.



List - also contains search, filter, and sort functions Frequencies - can be used to diagnose bearing damage within an application Fitting Practice - suggested bearing seat tolerances for various conditions Install Calc. – calculations useful for installation of bearing inner & outer rings Bearing Life – L10 life and adjustment factors for a single bearing (for multiple-

bearing life predictions, see Applications) Rolling Torque, which estimates the amount of torque generated by the bearing

under operating conditions Tolerances, which defines the tolerances on boundary dimensions for the selected

bearing Clearance Calculations, which predict the effect of temperature and tight fits on

bearing clearance or setting

4. Individual bearing calculations4. Individual bearing calculations


4. Individual bearing calculation4. Individual bearing calculation

Fundamental Frequencies This feature is available for all bearing types. It is not displayed for the list of needle roller bearing inner rings, as they are not meant to serve as bearing elements on their own, but rather are designed to be used in conjunction with another bearing. To determine fundamental frequencies on assemblies containing these needle roller bearing inner rings, access the Frequencies tab of the primary bearing being used.

GeometryApproximate information for internal geometry for the part number selected.

PlotDisplays the fundamental frequencies whose variable namesare checked at the top of the plot, for speeds ranging from zero to theOperating Speed. Note that f0 and f1 have the same value.



Bearing informationGives basic part number and boundary dimensions.

Operating SpeedFor evaluation of a range of frequencies, enter the maximum value to be studied,

Frequency Coefficients The five frequency coefficients -abbreviated BPFI, BPFO, BSF, FTFI, and FTFO - are based on thegeometry of the bearing, and are not speed-dependent. Multiplythese coefficients by (RPM / 60) to obtain a frequency in revolutionsper second (Hertz) for a particular defect type.

Frequencies This shows a number of frequencies, labelled f0 to f6, which may occur as a result of various conditions, including eccentricity, out of round, damage (nicks or spalls), and size variation.

Speeds - This shows the relative speed between various components in the bearing (Inner Ring, Outer Ring, Cage, and Roller).



Fitting PracticeThis feature is available for all bearing types except Needle Roller and Cage Assemblies (which do not have inner or outer rings). It provides suggested fitting practices for certain application conditions. While final selection of fitting practice must be based on experience, installation requirements, and bearing performance, these guidelines can be used as a starting point.

Bearing class input.Defines the tolerances on the bore or outer diameter of the selected bearing.

Ring selectionThe selected ring is highlighted in a blue color within the small picture.



Rotating/Stationary Shaft Select whether or not the shaft and the inner ring are rotating.

ConditionsSelect whether the inner ring needs to be easily displaced (axially) on theshaft.

Note: The field “Conditions” shows options only after the rotating / stationary shaft selection is made.



Results Suggested fitting practice. Both the inner ring bore (or outer ring OD) and the suggested shaft (or housing) dimensions for the bearing seat are listed, as well as the resulting fit.



Tapered Roller BearingsOne additional field is present on inner ring (cone) fitting practice for Tapered Roller Bearings:• The field is named “Loading conditions”

Loading Condition Select the application type or load levels.

Shaft Surface Select whether or not the shaft is ground at the location of the bearing seat.



Spherical Roller BearingsOne additional field is present for Spherical roller Bearings when housing fitting practice is selected and“Stationary Inner Ring Load” is selected for shaft fitting practice:• The field is named “Examples”

Examples Select the most similar application



Inner Ring FitDefine the minimum and maximum fit for the selected bearing ring.Negative values denote tight fits, while a value of zero denotes a line-to-line or loose fit.

Installation CalculationsThis feature is available for all bearing types except Needle Roller and Cage Assemblies (which do not have inner or outer rings) and Thrust Bearings.It calculates a number of values that can be used to evaluate installation forces to assemble bearing rings on shafts or into housings, as well as certain dimensional changes and contact pressures under tight fits, axial loading, or (for some outputs) both at the same time.

Note:

If the Fitting Practice function was used previously, those fits are automatically transferred over to the Installation Calculations function.

Shaft or Housing information This includes a shaft inner diameter or housing outer diameter, a friction coefficient between the bearing and shaft or housing diameters, and the name of the shaft or housing material.



Review of input data This section displays the inputs used to perform the calculations.

Fit Effects Only - This section considers only the effects of tight fits, if entered. These results are generally focused on the forces required to press the ring onto the shaft or into the housing.

If the contact pressure between the bearing inner ring and the shaft is more than10% different than the value that would be calculated with a solid steel shaft, awarning message is displayed. This reminds the user that the "holding" pressurebetween these two components may require additional evaluation to ensure thatit meets the needs of the application.

Fit + Axial Load Effects This section (visible for tapered roller bearings only) calculates a few values which consider both fits and axial loading.These results focus on how the shaft or housing is influenced by these twoeffects.

Axial Load EffectsOnly present for tapered roller bearings. These results consider the impact on the bearing ring and the shaft or housing of applied axial load after the bearings are installed.Line-to-line (zero) or tight (negative) fits are expected as the starting statefor these calculations.



Bearing LifeThis feature is available for all bearing types. It permits the user to describe loads applied to a bearing, as well as a limited description of the local environment, and calculate a catalogue bearing life.

Axial LoadThis is the axial load applied to the bearing, if the bearing type supports axial load.

Radial Load This is the radial load applied to the bearing, if the bearing type supports radial load.

Lubrication Factor - If this box is checked, the Catalogue Lubricant-Life Adjustment factor will be applied to the result.If unchecked, this factor will be fixed at 1.

Low Load factorIf this box is checked, the Catalogue Low Load Life Adjustment factor will be applied to the result. If un-checked, this factorwill be fixed at 1.

Lubricant NameSelect a lubricant from the list. If the required lubricant name is not yet defined, see the Custom Lubricant Definition feature for instructions on defining properties for a new lubricant.

Operating SpeedThis is the relative speed between the bearing rings.No differentiation between a rotating inner ring or a rotating outer ring is made at the catalogue analysis level.

Lubrication TypeSelect whether the bearing is oil- or grease-lubricated.This impacts the calculation of the lubrication-life adjustment factor.

Operating Temperature This is the temperature of the lubricant within the bearing, used to calculate the viscosity of the selected lubricant. This viscosity is used when determining lubricant film thickness and the resulting separation of the rolling element and the raceways.

The bearing capacity (rating) – C1 for a 1 million revolution baseline, C90 for a 90 million revolution baseline – is listed to the right of the inputs.

Once sufficient input data are present, the results are updated in the lower part of the screen.



Single-Bearing LifeThis feature is available for all bearing types. It permits the user to describe loads applied to a bearing, as well as a limited description of the local environment, and calculate a catalogue bearing life.

Low Load Factor - a3p Adjustment to the Catalogue L10 life thatconsiders the fact that bearing life has been shown to exceed the standard catalogue life calculations at lighter loads, when other environmental conditions permit.

Cg Factor - This is a constant specific to each bearing, defined by the bearing geometry, and used for the purposes of calculating alubricant-life adjustment factor.

Adjusted L10 Life This is [L10 Life] x [a3l] x [a3p], or the Catalogue L10 life multiplied by the Lubricant-Life Adjustment Factor and the Low Load Factor.

Lubricant-Life Adjustment Factor – a3l Adjustment to the Catalogue L10 life that considers the effects of lubricant films within the bearing.



Rolling TorqueThis feature is available for Single Row and Double Row Tapered Roller Bearings. It provides an estimate of roller-raceway torque under user-defined conditions. Torque created at the contact between the cone large rib and the roller large end is not included, but the applied speed and load are used todetermine whether this value would be significant.

Rolling Torque Results

o Viscosity @ Operating TemperaturePredicted viscosity of the selected lubricant at the user-defined operating temperature.

o Bearing TorqueEstimated roller-raceway torque when the bearing is operating under the specified conditions.

o Heat Generation (power loss)Combines the Bearing Torque and the Operating Speed to predict the power consumed by the bearing under the specified conditions.

For a plot of the results versus speed, click on the Graphic tab.



Note the warning at the bottom of the screen. As with the numeric results, estimated torque values (and therefore, the power values derived from them) are under-predicted below a certain speed threshold.

Plotting parameterPlot Torque or Power versus one of four inputs:• Speed• Temperature• Radial Load• Axial Load The other inputs are kept constant.

Modify the range of values to be considered on the x-axis.



TolerancesThis function allows selection of precision classes for some bearing types:For Cylindrical and Spherical Roller Bearings, this includes RBEC classes 1, 5, and 6.For Tapered Roller Bearings, this includes classes K, N, C, B, A, and AA for metric-class product, and classes 4, 2, 3, 0, 00, and 000 for inch-class product.

Only one class is available for Ball Bearings and Needle Bearings.

Select Bearing Class



Clearance CalculationsThis function is available for all bearing types except Needle Roller bearings and Thrust Bearings. It can be used to calculate the effects on internal clearance or setting of mounting fits and temperature differences considering shaft and housing material properties.

Temperature Gradient Difference between the shaft andhousing temperatures, or the difference between the inner ring and outer ring temperatures.

Inner Fit (s) Two fit values should be entered for the inner ring, describing the range of possible fits that can occur with the given tolerance structure. Only tight fits are used for these calculations, so any loose fits will be treated the same as zero fits (line-to-line).

Outer Fit (h) Similarly, two fit values should be entered for the outer ring, describing the range of possible fits that can occur with the given tolerance structure.

Shaft Inner Diameter (ds) Inner diameter of the shaft at the location of the bearing inner ring.

Bench End Play (BEP)Axial setting between the two bearings in a "free" (or "bench") state, before the bearing rings are installed on the shaft and into the housing. Only positive values (representing clearance or endplay) and zero (representing line-to-line contact) are permitted. Note that Bench End Play is designated in inch units.

Mounting Determines the relative orientation of the two bearing rows. For Double Row Tapered Roller Bearings, this is automatically defined by the product geometry, so this entry is not visible.

Bearing Spread (L) Distance between the centres of thetwo cups. For Double Row Tapered Roller Bearings, this is automatically defined by the product geometry, so this entry is not editable. For pairs of Single Row Tapered Roller Bearings, it must be entered by the user.

Housing Outer Diameter (dH)Outer diameter of the housing at the location of the bearing outer ring. The default value is set to approximately ten times (10x) the bearing outer diameter.

Spacer Width Tolerance (SWT) Amount that the Bench End Play can vary from the nominal value described above. It is expected to be a bilateral tolerance, such that the Bench End Play value is the mean, and can vary by the Spacer Width Tolerance in either direction.So, the overall Bench End Play Range is (BEP - SWT) to (BEP + SWT).



Radial Internal Clearance (RIC) Enter the minimum and maximum radial internal clearance values for the bearings.

This stop sign appears as a warning if the fits are entered in the opposite order (the Loosest fit is tighter than the Tightest fit).

Allows the user to view the equations being used to calculate the change in clearance or setting within this part of the program.



Inner Fit Effect (Fi)Amount of clearance or setting lost due to a tight fit (if any) of the inner ring. Values are always positive.

Outer Fit Effect (Fo) Amount of clearance or setting lost due to a tight fit (if any) of the outer ring. Values are always positive

Clearance Loss or Lateral Loss (Fi + Fo) Sum of the Inner Fit Effect and Outer Fit Effect. It represents the total reduction in clearance or setting.

Mounted Clearance or Mounted End Play (MEP) Expected clearance or setting in the bearing after installation, with all components at ambient temperature. For Double Row Tapered Roller Bearings, the overall range will also be further expanded by the spacer width tolerance. Negative values indicate an interference or preload state, while positive values indicate a clearance or endplay state.

Temperature Effect (T)Amount of clearance or setting lost due to differences in temperatures between the shaft (with inner rings) and the housing (with outer rings).

RIC or MEP with Temperature Effect Final expected clearance or setting after the bearing rings have been installed into the system, and the components are heated to operating temperatures.It is equal to the Mounted Clearance or Mounted End Play minus the Temperature Effect


5. Application analysis5. Application analysis

The Application Analysis section allows the user model a bearing application consisting of bearings and gears on a shaft and a duty cycle of loads and speeds.Two (radial) bearing positions are defined, with optional thrust bearing positions. Gear forces, bearing loads and bearing lives are calculated and a report is created.The user can also define dimensional and minimum bearing life constraints for programmed bearing search and selection at the radial bearing positions.


5.1 Manage applications


To select an existing application from the list, click on the row containing the application. When selected, a sketch of the shaft within theapplication appears in the lower part of the screen, allowing the user a visual confirmation of the selection.


5. Application analysis5. Application analysis5.1 Manage applications

Duplicate selected application This creates a copy of the application that is currently highlighted in the list. This could be used to evaluate changes in application design options, or as an aid to defining a similar application.

Export selected applicationThis saves a copy of the currently-selected application to an external

“.mdb type” database file. This exported application file can then be shared with other users of the Timken Bearing Selection Guide 3.


5. Application analysis5. Application analysis5.1 Manage applications

Import an application file - “file type” suffix will be “.mdb”This allows a user to “import” an application file from another user to the local list. Imported applications have the word “(Imported)” appended to the application name.

.NOTE: some anti-virus protection software does not allow import of “.mdb” files as e-mail attachments.The “Text File” Export / Import options can be used as an alternative to “.mdb” files.

To import applications from the 2003 Timken Tapered Roller Bearing Guide (TRBSG) v2.0a, select Import TRBSG 2 Application Files from the Utilities menu on the main screen.


5. Application analysis5. Application analysis5.2 Define Input Data for an Application – Application definition

This data can be filled in according to the user's own categorization system.

Click the Next >> button to go to the Shaft Definition screen.

Indicates the progression of the data entry step by step


5. Application analysis5. Application analysis5.2 Define Input Data for an Application – Shaft definition

This screen allows the user to define the geometry of the shaft within the application.

NOTE: The catalog application analysis method does not consider shaft bending analysis, but a well-modelled shaft helps in visualization of the application.

Shaft geometry is built up as a series of one or more cylindrical segments, ordered from left to right. All shafts start with the left end at X=0.

To add a segment to the right end of the shaft, click the Add button. This adds a new row to the end of the list, allowing the user to enter the geometry of that shaft segment. To remove a segment, select it by clicking once on the row that describes it, then click on the Delete button.

X=0



This can be used for generating approximate shaft geometry, or for creating a rough shaft design that is later refined using the numeric inputs above.

Click and drag any of those handles to resize the shaft segment.



If clicking on a shaft segment in the picture does not select it, the Zoom feature may be active.In this case, click the Normal button to restore the default cursor.

Click on the Redraw button to restore thedrawing to a scale that permits the entire shaft to be seen at once.

Click the Zoom button to look at part of the shaft in more detail, then click and drag on the sketch to form a box around the section of interest. The display then zooms in to that section of the sketch.



Zoom view


5. Application analysis5. Application analysis5.2 Define Input Data for an Application – Gear definition

This screen permits the user to define any gears that are present within the application.If there are no gears (loading is from other external sources), click the Next >> button to continue on to the Loading Data screen.

To add a gear to the end of the list, click the Add button.Next >> button


To remove a gear, click on the row that contains the information for that gear, and click the Delete button. A confirmation warning is shown before deleting the gear.

5.2 Define Input Data for an Application – Gear definition


To change the geometry or location of a specific gear, click on the row that contains the information for that gear, and click the Edit button.

A double-click on the sketch of the gear in the drawing will have the same effect as Edit button

Click on a particular value (such as the Location or Pressure Angle) in the row corresponding to a specific gear, and edit it directly in the table.


5.2 Define Input Data for an Application – Gear definition


Enter the appropriate data for the selected gear. Basic gear information is entered in the top part of the screen.

Additional gear information is listed in the lower section, if required for the selected gear type.

This lower section is labeled "Cylindrical", "Bevel", "Worm gearing", or "Hypoid", depending on the category of gear selected under Gear Type

When completed, click on button


5.2 Define Input Data for an Application – Load definition


This screen permits the user to define a duty cycle. It may contain multiple conditions, each occurring for some percentage of the time, and each condition can contain external loads as well as power or torque transmitted through gears.

To add a new condition to the duty cycle, click the Add button to place the new condition at the end of the cycle.

Click the Insert button to add a new condition immediately above the currently-selected condition.




To modify a condition, select it and click the Edit button.

To remove a condition, select it and click the Delete button.




Condition CommentThis is used to identify a specific duty cycle condition

MagnitudeThis is the amount of power or torque applied to each gear that has a defined mesh point in this condition

Direction of rotation – As viewed from the left end of the shaft (looking in the "+x" direction), this is the direction of rotation for the shaft in this condition.

Percent of time•This is the relative amount of time that the application spends in the current condition.•If there is only one condition defined, andthe application operates under those parameters constantly, enter 100.•The sum of the percent time values for all conditions is shown at the bottom of the list. •No weighted lives can be calculated if the total time for all conditions does not add up to 100%.External loads only

Check this box if the only forces on the system are from user defined external loads. Doing so will disable the two entries for the Magnitude line, which are only used when forces are derived from torque transmitted through gears




Select the Force Type first (RADIAL or AXIAL) to configure the proper inputs on the rest of the screen.

A radial external force is defined by a Location (along the x-axis), its Magnitude (which must be positive), and the Angle at which it is applied.

The Location and Angle conventions are illustrated in the picture in the lower part of the screen

An axial external force is defined by a Location (along the x-axis), its Magnitude, and the Angle at which it is applied, as well as a Radius that determines its offset from the shaft centerline.


Notes:● All forces are considered to be acting on the shaft (and not on the housing or directly on the

bearings, although forces can be applied to the shaft at the bearing locations).

● An external force must be defined separately for each condition in which it occurs. If external forces for the wrong condition are shown, select the proper condition at the top of the screen first before proceeding.

● Forces created by power or torque transmitted through the gears should not be entered here if the power or torque is defined in the next section along with the gear mesh points. Gear forces will be automatically calculated in that case and applied to the system.

● External forces can be defined as radial or axial. If the loads on the shaft in a particular condition contain both axial and radial components (or more than one of the same kind), multiple external force entries should be defined for that condition.

● To simulate loads applied to a common housing between all bearing positions, instead of the shaft, reverse the direction of the applied forces in this model. So, to obtain the correct bearing reactions for a radial load applied to the housing, enter a radial load applied to the shaft at 180° from the angle at which the load is actually applied to the housing, and at the same x-location.






If at least one gear has been defined, and a Power or Torque value has beendefined for the current condition, points where the gears are in mesh ("gear mesh points") can be defined in the Power Flow section of the screen.




Gear name - Select the name of a gear that is transmitting power or torque.

Percent of Power - In many cases, all of the power defined for this condition is transmitted through the specified gear mesh. In that case, a value of 100 should be entered here. If only part of the specified power (or torque) is being transmitted at the current gear mesh point, a smaller percentage can be entered instead.

Power Factor - Choose whether or not this particular gear mesh point is driving (applying force to another gear) or driven (being acted upon by another gear).

Mesh Angle - Enter the angle where the selected gear is in mesh with a mating gear on another shaft (The mating gear is not represented in this single-shaft model.) This angle is measured clockwise from the top of the shaft, as viewed from the left end of the shaft (looking in the "+x"direction). This is illustrated in the sketch at the bottom of the screen.


Notes:● A single gear may have more than one mesh point. An idler gear, for instance, would typically

have both a driving mesh point and a driven mesh point. These would be represented by two separate power flow entries at different angles.

● If there are multiple gears on a shaft, power will often enter through one gear (with Power Factor set to "DRIVEN") and exit through another gear (with Power Factor set to "DRIVING"). However, if the power is split (multiple input or multiple outputs), a separate power flow entry is required or each active gear mesh point, and the percentage distribution of power among the multiple inputs or outputs must be defined by the Percent of Power values for each.






To generate a Loading Cycle plot, click on the Graph button.

For duty cycles with multiple conditions, it may be helpful to view a summary ofthe speed and power (or torque) defined for each condition.




Bearing rotational speed plot

Magnitude (power or torque) plot


5.2 Define Input Data for an Application – Bearing definition


The final input screen of the Application Analysis feature allows the user to define individual bearing positions. Initially, only the shaft, gears, and external forces are shown. Bearings must be added to complete the model.


Bearing Position Definition Rules (Catalog Method Calculations)

Valid system configurations must follow these rules:

● Two radial bearing positions are required

● Single Row Tapered Roller bearings must be used in opposed (apex direction) pairs● Spherical, Ball, and (some) Cylindrical bearings can support axial load, but only one

position of the two can be “FIXED” to support axial load

● Two thrust (support axial load only) bearings can be defined

● If thrust positions are defined, both radial bearing positions must be FLOATING ● A thrust bearing can only support axial load in one direction ● Both thrust positions cannot support axial load in the same direction

The icons of bearing types which cannot be added to the current configuration are "grayed out". To add in a bearing type that is currently grayed out, first remove one or more bearing positions from

the current model.






To make a copy of an existing bearing position, select that bearing by clicking on it once, then click on the Copy button that appears near the top of the screen.

To add a new bearing position to the application, click on the corresponding bearing type icon from the list at the left of the screen.

To delete an existing bearing position, select that bearing by clicking on it once, then click on the Delete button that appears near the top of the screen.

To change the direction of a bearing (if available for this bearing type), select that bearing by clicking on it once, then click on the Flip button that appears near the top of the screen.




X

To move a bearing, Click on its image from the main sketch and drag it along the shaft

To modify a bearing, double-click on its image from the main sketch in the middle of the screen.


Location ReferenceThis determines the geometric point or face on the bearing that will be used to define its axial location.



LocationThis is the x-coordinate in the model where the specified bearing point or face (defined under Location Reference) is located.

Operating Temperature This is the overall, steady-state temperature of the lubricant (oil or grease) within the bearing during operating conditions.

Shaft OD at LocationThis is not editable by the user, but displays the outer diameter of the shaft at the specified Location coordinate.


StatusFIXED or FLOATING mounting options are available for most radial bearing types and determine if the bearing at this position can support axial loads.



A FIXED (can support axial load) bearing is shown with an "X" symbol at the center line.

A FLOATING (cannot support axial load) bearing is shown with a "="symbol at the center line.




Axial Load (Cylindrical Roller Bearings) - This determines the direction(s) in which a bearing can support axial load. This is a function of the flanges (or ribs) on the two rings. If the flange configuration of this particular bearing selection cannot support any axial load (such as when one of the rings has no flanges), choose NOT SUPPORTED.

Style (for Tapered Roller TS or TSF Bearings only )The two options are SINGLE APEX LEFT and SINGLE APEX RIGHT which determine the direction that this bearing row is facing.

SINGLE APEX LEFT SINGLE APEX RIGHT




Axial Load (Thrust Bearings) - This determines the direction in which a thrust bearing can support axial load. Select TO THE LEFT or TO THE RIGHT, depending on whether axial loads to the left or to the right on the shaft can be supported by this bearing.




Bearing SearchTo select a bearing based on envelope dimensions, click the Bearing Search button

Enter the target range for the Bore, Outside Diameter, and Width of the bearing, and click the Look up button to generate a list in the table below. Notice that the default range for the bore is +/-10% of the Shaft OD at Location value listed on the previous screen.




Bearing SelectionTo select a bearing based on envelope dimensions and required life, click the Bearing Selection button




Result windowArea for display of Left position search results.

Result windowArea for display of Right position search results.

To use the selected bearings, click on the “Accept” button.

Constraint parametersEnter the target range for the Bore, Outside Diameter, and Width of the bearing, as well as the Minimum Adjusted Weighted Life.

Search to start the process

Life calculationsDepending on the bearing candidates selected (highlighted in Blue), the results of the bearing life calculations are given here.

OptionsClick here to define the bearing positions to be considered in the selection.


Low Load Factor - Low Load factor (a3p) for this condition in the Duty Cycle.

Lube Factor - Lubricant-Life factor (a3l) for this condition in the Duty Cycle.

Axial - axial load on the specified bearing position for this condition in the Duty Cycle.

Radial - radial reaction (load) on the bearing position for this condition in the Duty Cycle

5.3 Calculation results


Low Load FactorIf checked, the Timken Catalog Low Load Factor (a3p) will be applied.

Lube-Life FactorIf checked, the Timken Catalog Lubricant-Life Factor (a3l) will be applied.

Note that Radial and Axial reactions are based on certain catalog assumptions, and may not match more advanced system deflection models.It considers not only the bearing load and speed, but also the Low Load and Lubricant-Life adjustment factors, if selected in the Calculation Parameters section.

Based upon Catalog Life assumptions, it is the life to which 90% of a population of apparently identical bearings is expected to run before experiencing a certain amount of damage.

Lubricant ModeSelect whether the bearings use OIL LUBRICATION or GREASE LUBRICATION.

Lubricant SelectionChoose a lubricant name from the drop-down box.

Note:Bearing loads and life predictions calculated by the Timken Bearing Selection Guide are based on the methods and formulas described in the Timken Products Catalog – Engineering Section. The effects of lubricant film and low “effective” load can be considered through two life adjustment factors.

Adjusted Life - adjusted Catalog L10 Life (90% reliability) for this condition in the Duty Cycle.

Life - Catalog L10 Life (90% reliability) for this condition in the Duty Cycle.


5.3 Calculation results


Select the condition of interest from the Viewed Condition drop-down box.

Click the Report button to view or print the Report.

Click the Summary button to view or print the Application Summary.

Click the << Previous button to return to the Loading Data screen.


5.4 Application Analysis - Summary


The Summary view is a short overview of the inputs and outputs for an Application Analysis, formatted for viewing or printing.

View of page 1 View of page 2

The first page summarizes the Duty Cycle, including information about each condition, as well as radial and axial reaction loads on each bearing position.

The second page describes additional calculation parameters and other inputinformation, and then lists the predicted Catalog and Adjusted Catalog lives for the bearings.


5.4 Application Analysis - Summary

Move to the first page in the current report.

Move to the last page in the current report.

Move to the next page in the current report.

Move to the previous page in the current report.

Increase the size of the display.

Decrease the size of the display.

Set the zoom level to a particular amount or size it to fit the available screen.


Click Save as PDF to export the report as an Adobe® PDF Document.

Click Copy to Clipboard to store the currently-visible page on the Windows clipboard, where it can then be pasted into other applications that support the copied format


5.5 Application Analysis - Report


The Report view is a detailed compilation of the inputs and outputs for an Application Analysis, formatted for viewing or printing. It is accessed by clicking the Report button from the Application Analysis Bearing Definition screen.


Timken Bearing Selection Guide IIITimken Bearing Selection Guide III

Actual bearing performance is affected by many factors. Therefore, the feasibility of all bearing applications should be validated by the customer. The data in this training material is intended for reference purposes to assist your effort in selecting bearings for a given application.

rev 2008-03-20 SCM

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Rev 2008-03-20 SCM Welcome to the Bearing Selection Guide v.3.0 The ultimate calculation tool