Hints, Helps, and Questions Answered

SIZING your Bearing / Bushing …


Always use Vesconite's calculation programs or charts to properly size your application. This is the most important thing to do to ensure a successful installation!


Vesconite products, as with all non-metallic materials, expands and contracts at different rates than bronze or other metallic bearings. Therefore, this has to be taken in to account when calculating the proper bearing retention and operating clearances.Even though VESCONITE and Vesconite HiLube may have a much larger amount of interference, the actual retention pressure is much the same.


Similarly, all the machined sizes, ID., O.D., etc. will be different than if using bronze.  But once you use the calculation program, all standard conditions are taken into consideration.


Presently, sizing information is available on the web site for Standard VESCONITE and Vesconite HiLube.


Click here to go to the Sizing Calculators. When sizing Vesconite HiTemp, contact us for specific instructions or, if you have any other questions, feel free to contact us.





How does VESCONITE and Vesconite HiLube MACHINE?...


VESCONITE and Vesconite HiLube machine very easily. Generally, if you have machined aluminum, you can easily machine Vesconite. Basically, use the same feeds and speeds as aluminum.


Click here for additional machining help.







Be sure to consider the temperature that the bearing will operate at, as well as the temperature during maintenance and non-operating times.


Example: a ship that travels from Alaska to Hawaii will see water operating temperatures from 28 °F in Alaska to 89°F in Hawaii, but the bearing may see (minus) -20°F if the vessel is pulled out of the water in Anchorage.  Therefore the temperature range is

–20°F to +89°F.





Worried about BEARING RETENTION...


Bearing Retention depends on the specific application in which the bearing material is being used. Some things to consider are:


Additional retention pressure can be achieved by increasing the I.D. and O.D. by a small amount. This can be easily calculated by lowering the minimum operating temperature when using the calculation programs.


With heavy loads and axial applications, retaining rings on each end may be required. This will restrain the bearing making sure it will not spin out of the housing.


Three ways of securing a Bearing are Interference fitting , Mechanical, and Bonding.


Click here for Bearing Retention information.





What about WATER GROOVES ...


Water grooves are a necessity in all Stern Tube Bearings and almost all Pump applications.  Water flow through the bearing helps cool the bearing as well as helps the debris flow through the bearing.


Different applications may require different groove configurations, but in most applications straight grooves will work just fine.  Use Vesconite’s Calculation Programs to determine the number and size of grooves to be used.


When installing a shaft into a bearing with water grooves,  Do NOT use grease or other thick lubricants.  This will clog the grooves and render the grooves useless.


Click here for Water Groove information.







Operating Temperature is an important consideration when using any non-metallic bearings.  Vesconite’s products have excellent temperature capabilities when used within the guidelines.


Both Standard VESCONITE and Vesconite HiLube can be used in temperatures up to 212°F (100°C) Dry and 176°F (80°C) Wet. For use in temperatures between 158°F (70°C) and 212°F (100°C) an expansion gap is necessary maintaining proper bearing retention. See the calculation program for details.


Vesconite HiTemp products can be used at much higher dry temperatures, up to 392°F (200°C) Dry and up to 248°F (120°C) in Wet environments. HiTemp products may also require an expansion gap when installed and normally requires a slightly larger running clearance.  Please contact us for details.




LOW TEMPERATURE Applications...


These conditions are generally addressed in the Design-a-Bearing sizing Calculators. For specific information on low temperature design considerations...

Click here for Guidelines on





What about using Vesconite products with SPECIFIC CHEMICALS…


The various Vesconite products react differently in regards to the different chemicals that come in contact with the bearing materials.  The basic chemical resistance property for each product is listed on the Chemical Resistance page.  Keep in mind that concentrations should also be considered.


If you have any questions on a specific chemical solution or concentration, please contact us for assistance. Email Us






What about Housing and Shaft Material considerations...


As a "general rule of thumb" the bearing should be softer than the shaft material. Questions: What surface do you want to wear out first?   What surface is cheaper and easier to replace.?   Generally, the harder the shaft the better.


Another consideration is corrosion resistance.  With nonmetallic, water lubricated bearings, the grease (a corrosion protectant) is no longer available, therefore allowing rust to form, increasing wear.   A corrosion resistant / hard shaft may be important.


Surface finish on the shaft is also important. We recommend a 20 rms finish.


Click here for more Housing and Shaft information considerations.




How does VESCONITE and Vesconite HiLube compare against other materials? ...


Frequently asked questions on comparing Vesconite materials to other materials.


Click here for the link to Vesconite's FAQ page.





What’s the difference between VESCONITE, Vesconite HiLube and Vesconite’s HiTemp products?


VESCONITE and Vesconite HiLube products differ from Vesconite’s HiTemp products. HiTemp is “generically” a glass filed nylon with special proprietary chemical properties to withstand the elevated temperatures. Although there are different material characteristics, HiTemp, when used in specific parameters performs extremely well in dirty water / high temperature applications.


Contact us for more information. Email Us





What do the Technical Terms mean? ...


For a fairly complete list of technical term definitions, Click here for a  Glossary of Technical Terms.





Have Questions, Not sure of a particular application?


That’s what we’re here for. Both Hydro-Watt and Vesconite have years of various application experience that is at your disposal. Feel free to contact us. If we don’t have an answer, we’ll help you find it.


Email Us

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Phone: (530) 265-5099

Fax: (530) 265-9411

22792 State Highway 20

Nevada City, California 95959 USA