O-Ring Calculator

SPEAKER NOTES

Imagine yourself stuck while installing an O-Ring in a hardware application.

‘Trelleborg Sealing Solutions’ supports you in finding the right solutions.

Let us see an example of an automotive industry using an O-Ring for a convertible (cabriolet).

The retractable roof mechanism of the car is having some problems.

What could possibly be wrong with the roof mechanism?

This could be because of an improper groove or the O-ring design.

Here you can see another example of a car with a properly functioning convertible and with the correct O-Ring installed.

Sam is an engineer in an aviation firm and he is finding difficulty in getting the exact size of the O-Ring seal which needs to be installed in the aircraft actuator.

Sam knows how to solve this issue to get a right seal application, by using the O-Ring Calculator tool, however, not so sure how to use it.

Let's help Sam in understanding the appropriate usage of the O-Ring Calculator in our upcoming slides.

Is there a tool for selecting proper O-Ring?

Which helps in finding the right hardware/groove dimensions?

Which material to be selected?

What installation force is required?

This e-Learning lesson will help to find a suitable O-Ring Solution for your hardware application.

Welcome to this e-learning lesson on the Trelleborg Sealing Solutions O-Ring calculator.

The O-Ring Calculator digital tool helps to determine parameters for the layout of O-Rings and their housing.

It’s a user friendly tool, which provides support in multiple languages and gives accurate results.

As helpful as this tool is, it does not replace sealing layout expertise!

In this lesson, you will be shown how to use the O-Ring Calculator in the most efficient way. O-Ring Calculator helps you to choose an appropriate O-Ring with set parameters. It also helps you to share your projects with your colleagues through the calculator.

This lesson will take approximately 20 minutes to complete. We hope you enjoy it.

Let us go through the process on how to access the O-ring calculator:

Open the TSS website and click on the tab “Tools & Resources”

Select “Design Support & Engineering Tools”.

Select the O-Ring Calculator.

Enter your login credentials and log in.

Now the O-Ring Calculator application is ready to use.

This provides suitable O-Ring sizes and housing dimensions in accordance with ISO 3601 calculated for ambient temperatures. In accordance with ISO 3601 recommendations, the calculator always suggests the thickest possible O-Ring with the appropriate housing according to ISO 3601, Part 1 and 2.

The preselected application type is used as a pre-condition for the calculation - different limits are applied which lead to different results.

After entering the appropriate application diameter, depending on the application type either Bore-Ø, Rod-Ø or Groove Outside and Inside diameters, this function selects a suitable O-Ring size in accordance with ISO 3601-1 and automatically calculates an O-Ring housing in accordance with the recommendations of ISO 3601-2.

Open the function by clicking on the “ISO Search“ button.

Fill in the appropriate application diameter and click search.

Calculator displays the available O-ring part numbers with inner dia d1 and cross sections d2 from ISO sizes.

Appropriate housing dimensions are calculated in the background.

If you agree with the O-Ring size, click on Apply.

Get the O-Ring and housing dimensions and tolerances filled into the appropriate input fields

Get the Trelleborg Sealing Solutions part number for the O-Ring size

Get the appropriate calculation results based on this input

In case no results are displayed then no suitable O-Ring - housing combination can be found in accordance with ISO 3601-1 and -2. An individual calculation is necessary.

Now, we have covered all the chapters. Let us summarize.

This is the O-Ring Calculator user interface. It is assessable in English,German,Chinese and Japanese. Select your preferred language.

Let us explore the user interface in detail.

Right below the language options you can see “My Saved Results” where you can save the results of your calculation.

Next to that you can see “Other App's” option which takes you to other App's which is available in TSS website.

You can switch it to inch or millimeter from the system unit option.

For the selection of the application type, there are three tabs.

To know more about these tabs click on the “More info” button.

To start with your calculation, choose your preferred unit system, Metric or Inch.

Then select the kind of application for which you are going to calculate the layout and specify it.

For Radial Outer and Radial Inner sealing applications, choose between static and dynamic.

For Axial Static Sealing applications choose between Internal and external pressure.

This pre-selection is the basis for all calculations and valid limits for warnings.

Let us take a look at the Mandatory data inputs.

Click the ok button to continue.

In a radial outer sealing application, the O-Ring is used as either a static or dynamic piston seal. The O-Ring size should be selected so that the inside diameter is equal to or smaller than the groove diameter.

In a radial inner sealing application, the O-Ring is used as a static or dynamic rod seal. The O-Ring size should be selected so that the O-Ring outside diameter is at least equal to or larger than the groove outside diameter to ensure an outside diameter interference.

In axial sealing applications, the O-Ring is predominantly used as a static seal, for example, as a cover or flange seal. During axial-static installation, the direction of the pressure should be taken into consideration when choosing the O-Ring size.

If there is internal pressure, the O-Ring should be chosen so that the outside diameter of the O-Ring is approximately 1% to 2% larger than the outer groove diameter.

If there is external pressure, the O- Ring should be chosen so that the inside diameter d1 of the O-Ring is approximately 1% to 3% smaller than the inner

groove diameter.

This is a switch to check the differentiation between static and dynamic applications and to define the pressure type.

You can add your individual notes here.

There is an option to adjust the zoom.

This is the section to enter all mandatory data.

Optional data can be entered in this section.

Note: Input fields are always white. They turn off white when activated. They get a red frame in case of a related warning message.

O-Ring calculator offers engineers and professionals a quick and easy way to calculate O-Ring dimensions and the appropriate housing layout in accordance with the international O-Ring standard ISO 3601.

By simply entering installation specifications for an application, it recommends O-Ring sizes, housing layout, and corresponding part numbers.

The output section provides values for determining the layout parameters and also provides Trelleborg Sealing Solutions part numbers.

Appropriate parameter descriptions are shown in the info buttons.

Use this icon to open the email dialogue box, now you can share the calculation results to your colleague through e-mail.

Use this icon to download the results as a PDF file.

The Save button will help you to store the result for later reference.

Let us see the optional Entering data.

Click the ok button to continue.

Mandatory data input

The O-Ring calculator works out values of the parameters for the sealing function of an O-Ring based on existing Hardware and O-Ring dimensions entered into the input fields. The input block has mandatory fields that must be entered in order to get the results calculated.

These are the optional fields to enter additional data when specifying your calculation.

In case the operating temperature deviate from an ambient temperature of 23 °C, a different temperature can be entered.

This will only have an effect on calculation results if a material group is selected or a linear thermal expansion coefficient is filled in the appropriate field manually.

In case the O-ring material thermal expansion coefficient is not known and the total compression forces need to be calculated, then a standard material group from the drop down needs to be selected. The related linear thermal expansion coefficient will then appear automatically in the appropriate field. When filling in an individual thermal expansion coefficient, the selected standard material group will disappear again. For more details on the thermal expansion coefficient click on the button.

Only the expansion of the O-Ring is considered for the calculation. Hardware expansion is disregarded.

The O-Ring Material Hardness must be entered if the total compression forces need to be calculated. By Default, hardness is taken as none. For more details on Hardness click on the button.

Ensure you enter proper temperatures for the selected material. Temperatures out of the recommended materials operating temperature range will activate a warning message.

Linear thermal expansion

Most materials expand through heating and contract through cooling down, known as thermal expansion and contraction.

The coefficient of linear thermal expansion is a material constant which describes the thermal expansion of a material within a defined temperature range.

Elastomers generally have a higher coefficient of thermal expansion than metals.

O-Ring Material Hardness

One of the most frequently mentioned properties in connection with elastomers is hardness.

In this context, hardness means the resistance of one body to penetration by an even harder body with a standard shape and defined pressure. In elastomer hardness testing, two typical procedures can be differentiated according to test procedure, indenter size and design: Shore A or D and IRHD.

For the calculations of the basic layout determining parameters, the volumes, temperatures, tolerances and linear thermal expansion co-efficient are considered. The input data on the mandatory fields play an important role for the output.

As mentioned before, the output data for radial applications provide calculation results for concentric and eccentric position of the piston or rod. For more information concerning eccentric position and extrusion gap click on the button.

Eccentric position

Especially in the case of a radial installation, the clearance between the sealed parts is larger and should be considered in the layout. Under pressure, the O-Ring can be extruded into the resulting gap and thus get damaged. Considering the Eccentric Position is important to avoid extrusion.

Lets see the Benefits of the basic calculation.

Click Ok to continue.

Let us see the benefits of the warning messages.

Click the ok button to continue.

The calculation of the compression force resulting from real initial compression of the O-Ring cross-section is something completely new. Total compression force values are calculated and displayed only when the material group and hardness are selected. Calculations are based on appropriate uniform loads and effective length of the O-ring selected and provide guiding values.

The warning messages that come up depending on application pre-settings, input data, and calculation results. Valid warning limits for input data refer to technical feasibility and for results refer to ISO 3601-2 limits or Trelleborg Sealing Solutions recommendations.

Warning messages can be ignored provided that input values don‘t impede further calculation (→technical feasibility) and evaluation of results can be self-contained. Warning messages are collected in a red box and can be shown by moving the mouse cursor over the red marked fields.

For example: After entering the hardware details and selecting the O-Ring size, warning messages pop up if there are any deviations from the specified limits.

This helps in understanding what might have gone wrong and in evaluating the calculation results.

By changing input data the results can be brought within the specified limits making the warning messages disappear.

Additional information on the appropriate input and output parameters are displayed as soon as the cursor is moved over the i-buttons.

What does this lesson cover?

Click the Next button to continue with the lesson.

Now let’s get started with the program. Click on the buttons to learn more about each topic.

Let us go through these icons for more information.

In this section, we’ll show you examples on how the O-Ring Calculator can be used. The examples show a calculation with free data input and, also, the ISO Quick search.

Let’s start the Process.

These are three different configurations for the selection of the application type. In Radial Outer Sealing, which is represented on the left side of the window, the O-Ring is mounted over the piston.

For Radial Inner Sealing, the O-Ring is installed inside the groove. The rod surface is the sealing interface.

In Axial Sealing, the sealing interface is exposed to pressure either externally or internally in the axial direction. This is similar to flange covers.

Taking an example for the Radial Outer Sealing. let us enter a value of 30mm for the Bore Diameter and 31mm for the Piston Diameter. Here you can see that since the Piston Diameter is greater than the Bore diameter a Warning message appears. Any general errors are taken care of by the software itself and ensure correct input by the user. By changing the input data, the values can be brought within the specified limits. This will allow the warning message to disappear. Let’s fill in the remaining hardware parameters.

For example, let’s take an O-Ring with an inside diameter of 25.1mm and a cross-section of 2.62mm.

Here we show the free input option where the user can enter the O-ring diameter and cross-section of any value. The tool will then check the suitability using calculation results with the provided hardware parameters.

In the free input option, no TSS Part No Number is shown in the box.

Also, no total compression force is calculated as we have not selected the O-Ring Material group and O-ring material Hardness.

Now let us take an example from the ISO Search option. Click on the Reset button and then click on the ISO Search tab.

The calculation Assistant opens. Type in a Bore Diameter of 30 mm and select results

After choosing the application bore diameter, the software gives the suitable O-Ring Sizes in accordance with ISO 3601-1 and the corresponding TSS part number.

You can select the suitable cross section if you feel that there is a requirement of higher or lower sealing area and Click on Apply.

The O-ring calculator will then give the hardware dimensions and the calculation results automatically for an ambient temperature of 23ºC.

You can see the O-Ring we selected in the free input is the same as the one suggested by the calculator.

By using ISO Search you also get relevant Trelleborg Sealing Solutions part numbers.

By entering the O-ring Material Group and the O-ring material Hardness, Total Compression Force will be automatically calculated.

By default, the temperature will be ambient at 23ºC. If you change it to 150ºC, you will notice a warning message. This occurs since the entered value is outside the recommended range.

By providing the correct temperature value, for example 100ºC, the warning messages disappears.

By changing to a higher cross section O-ring or by changing the hardware dimensions in the input block, the calculation results will be affected.

This helps to understand if the selection is correct. In this case, changing the cross section of the O-ring to 3.53 shows a warning message.

Changing the O-Ring size back to its original dimensions will make the warning message disappear.

Choose My Notes, if you would require notes for future reference, and then click on save. This also displays on the final pdf.

Here you can change the Unit System from Inch to Millimeter whenever required during the usage of the calculator. It will automatically change all the values of inputs and results.

You can also change the language any time during the calculation without restarting the calculation.

To share the calculations with your colleague or with your customer, you can send a mail just by providing there email ID and send.

Now you can download “PDF” file of your calculation.

You can see the general layout recommendation on the first page and calculation results with individual notes on the second page of the file.

The O-Ring Search offers the selection of O-Ring nominal sizes according to different national and international standards.

Open the function by clicking on the “O-Ring Search“ button.

Choose relevant standards

Choose one of the appropriate O-Ring Cross-section-diameters

Choose one of the corresponding O-Ring Inside-diameters

Click on “Apply”

You will get the selected O-Ring dimensions automatically filled into the appropriate input fields and the relevant Trelleborg Sealing Solutions part number.

Thank you for participating in this lesson.

We wish you every success in putting your new knowledge to work in practice.

Please also try our other lessons on O-Rings.

Your opinion is important to us. Please take the time to answer the questions in the feedback form by clicking on the Evaluation button.

Or click on the Finish button to quit the lesson.

Goodbye!

Which of the following statements on the synthesis of Zurcon® TPU at Trelleborg are correct?