GGB tribological solutions move the industrial world one step closer to the future. Our products are used in tens of thousands of critical applications every day—around the planet. Our goal is to provide reliable, maintenance-free surface solutions for almost any application—no matter where those demands take our products.
GGB's diverse polymer coating solutions encompass some of the most state-of-the-art coating technologies available. Our TriboShield® product line includes seven standard formulations that cover the full spectrum of mechanical, thermal and chemical capabilities offered by today's coating materials. They can also be applied to nearly any surface, regardless of shape or material, making their potential almost endless. And when it comes to working with and enhancing the performance of your existing bearing and polymer coatings solutions, our TriboMate product line is specifically designed to be paired up— all leading to enhanced performance.
The excellent low friction and high wear resistance performance of GGB metal-polymer bearings make them ideal for hundreds of applications in numerous and diverse industries. Depending upon application requirements, metal-polymer composite bearings can be produced in many shapes and sizes.
GGB's Engineered Plastic Polymer bearings provide excellent wear resistance and low friction in both dry and lubricated operating conditions over a wide range of applications. Engineered plastic bearings are made from thermoplastic bearing material processed by injection moulding. This production method enables us to produce unlimited dimensions in accordance to our standard, and also parts with special designs and features.
GGB's Fiber Reinforced Composite products typically consists of a filament-wound, fiberglass-impregnated, epoxy backing with a variety of low-friction wear-resistant bearing linings. These self-lubricating fiber reinforced composite bearings are particularly effective in applications where the relative motion is not sufficient to promote circulation of the oil or grease used with more conventional bearings. GGB Fiber Reinforced Composite bearings are available as bushes, plates, bearing segments and special forms, depending on the particular material type.
Bimetal and metal bearings offer excellent corrosion resistance in industrial outdoor applications and in water, marine and offshore environments. GGB offers a broad range of sizes, forms and materials in monometallic and bimetallic bearings.
Engineered as a solution to conquer misalignment reduction when high demands are placed on bearings, GGB's UNI, MINI and EXALIGN® self-aligning shaft bearing assemblies offer improved equipment performance under standard bearing assemblies by reducing stress and friction. Offering superior performance in a wide variety of applications, GGB's self-aligning assemblies are available in both standard and custom configurations.
GGB has been putting the world in motion for over 120 years with industry-leading tribological bearings, coatings and assemblies. From Polymer Coatings and Metal-Polymer bearings to Fiber Reinforced Composite bearings and self-aligning shaft bearing assemblies, our solutions are specifically designed to reduce friction and optimize performance and durability.
Tribology is the science of wear, friction and lubrication, and encompasses how interacting surfaces and other tribo-elements behave in relative motion in natural and artificial systems. This includes bearing design and lubrication.
GGB’s TriboU is intended to provide the working engineer, who may or may not be a user of GGB’s surface engineered solutions, to understand and implement basic tribological concepts in the design, manufacture and use of industrial equipment.
At GGB, we aren’t afraid to take risks for our customers. We are passionate about the work we do and believe that same passion contributes to the level of innovation that can enhance human potential. We take pride in working closely with customers in the early stage of a design to think broadly and boldly, and to expand beyond traditional surface engineered solutions. We offer reliable partnerships based on trust, compassion, determination, collaboration and respect.
GGB seeks out collaborative, long-term relationships with each one of our customers. Our diverse expertise gives us a deep understanding of the challenges you face. When you partner with us early, our GGB engineering team is able to review your assemblies and make sure both the bearing and surrounding components are optimized for performance and cost-effectiveness.
Learn how to calculate specific load and sliding speed
Specific Load, also referred to as bearing pressure, is based on the forces that will be applied to the bearing over its lifetime. It is a function of the force and contact area of the bearing material. The SI (International Standards) units for Specific Load are Newtons per square millimeter (N/mm2), also referred to as Mega Pascal (MPa).
Sliding speed, also referred to as speed (U), is the relative sliding speed between the bearing surface and the mating surface (shaft, thrust face or liner slide surface). The SI units for sliding speed is meters per second (m/s).
The factors, MPa and U, are used to determine the suitability of a given bearing design and choice of bearing material to the various application requirements. For example, by first selecting a bearing material, the designer can specify the proper bearing dimensions that will meet the application requirements. Alternatively, by first determining the bearing dimensions the designer may then select a bearing material that will meet the various application requirements.
An important factor in designing for a dry bearing is the product of Specific Load (MPa) and Sliding Speed, known as the U factor. The U factor in combination with the coefficient of friction determines the rate of heat generated by thermal friction for a given dry bearing design which relates the bearing material’s ability to resist heat. GGB brochures list the , U and U limits for its various bearing materials.
In a lubricated application, the ability of a sleeve bearing to develop a hydrodynamic lubrication film between the shaft and the sleeve bearing surface is determined by the relationship between Specific Load () and Sliding Speed (U), the dynamic viscosity (centiPoise) of the lubricant and the bearing length-to diameter ratio (B/D). The relationship between these factors is: where the 7.5 value is a proportionality factor based on ISO units.
To determine the bearings capability of resisting permanent deformation under worst case scenarios we must first determine the maximum applied force, Fmax,. To determine the maximum force, which is critical to a robust bearing design, we must consider: anticipated design loads; load history based on other similar designs; measured loads; power source information like torque versus speed; shock loads. Maximum specific load, p max, is used to determine if the bearing material has sufficient load capacity to support the maximum load.
When determining bearing life for select GGB products, an average or weighted average bearing load, F, is used to determine if the bearing material will provide sufficient life when considering the sliding speed. The average bearing load is calculated when load data is limited to minimum and maximum values. If the load range is relatively small (less than 25%) between the min/max loads, then simply take the average of the two values. If the load range is relatively large then take 2/3 of the difference and add it to the minimum load for a “conservative” average. If a load versus time history is available, assuming a steady speed, then a weighted average is possible:
where tn and Fn are the times and loads respectively for each time/load increment and St.
When the speed varies, substitute the number of revolutions, n1, n2 ... nn and Sn for the time increments t1, t2 ... tn and St.
Now that the maximum and average forces have been determined, the specific load is very easy to calculate:
Sliding Speed, U, also called velocity, is usually not that difficult to determine especially in applications that are driven by motors or engines. Speed generates heat at the bearing/mating surface interface which, over time, will affect bearing performance. The greater the speed, the greater the amount of heat generated. Very slow or very occasional periods of relative motion may not develop sufficient heat to degrade the bearing material’s properties.
Speed, U, in meters per second, is calculated based on the basic type of application:
Continuous rotation:
Oscillating motion:
Linear motion:
Our experts are ready to help you find the right solution for your specific application.