Categories
Blog

Bearings in Extreme Environments: High Temperature and Corrosion Resistance

Due to the higher dependability, lower complexity, and reduced environmental effect of NBC high-temperature bearings and bearing units, these bearings in extreme environments are appropriate for use in trucks, rolling hearth furnaces, and bakeries. Expectations for the bearings in extreme environments used in vacuum environments have increased due to recent developments in the process technologies used in semiconductor production and other industrial sectors. These days, such bearings must be safer, more robust, and corrosion-resistant. In response, NBC Bearings created a bearing technology for ultra-high vacuum settings that uses solid lubrication.

Bearing Life

It is customary to calculate bearing life as follows. The next step is establishing the bearing size after choosing the right kind for the application. The catalog load ratings determine the basic rating life based on the loads and speeds, or duty cycle, and the bearings will encounter in the application. This is then compared to the required design life to determine the proper dimensions. However, the fundamental rating life is reduced downward as necessary in cases of extreme or hostile settings. The life adjustment factor might be as low as 0.1 in some situations. This indicates that only 10% of the calculated rating life can be anticipated due to environmental factors. In these situations, an engineer might have to create special bearings to lessen the effects of the working conditions or the environment. Materials for rings and rollers, coatings, seals or retention materials, and lubricants are some of the bearing components that can be replaced or created to order. Evaluate and consider the three situations that significantly impact life: high temperature, corrosive, and vacuum, before replacing or developing specific materials.

High-temperature environment

For temperatures above 350°C, special bearings have been developed. These bearings are employed in high-temperature situations, such as machinery near or inside ovens or furnaces, industrial blowers, engine applications, and conveying equipment used in all thermal processes. Designing a bespoke bearing for high temperatures requires considering the material and lubrication.

Corrosive environment

Many chemicals, marine environments, water exposure, and moisture exposure can all harm bearings (gas and liquid). At factories that process food, bearings undergo a daily high-pressure washdown using water and sanitizing or antibacterial chemicals. Similarly, submersible pumps used in irrigation systems are subjected to water containing sediment and fertilizer. In an automated paint line, the conveying equipment is exposed to several chemicals throughout the cleaning cycle and the paint itself. Both the bearing and the lubricant are put at risk in these conditions.

Vacuum Environment

With spacecraft and satellites, contamination of mission-critical components is a key concern. Outgassing substances may condense on optical components, including lenses, solar cells, and navigation sensors, in the vacuum of space. In the semiconductor sector, contamination from material outgassing can harm wafers worth millions of dollars. The retainer and lubricant are bearing components that should be considered in vacuum settings. These settings require ultraclean bearings. To remove volatile residues that might outgas, surfaces need to be cleaned with solvents and, in some instances, baked.

Customized Bearings

NBC Bearings provides a range of customized bearings in extreme environments and high-temperature bearings that adhere to ISO requirements. These bearings are customized for use in applications such as:
  • Ovens for baking wafers automatically in the food and beverage sector
  • Industrial furnace
  • Chains

Features and Benefits

  • Minimize total operating cost: The bearings have a durable lifespan because they are made to preserve the radial clearance required for high-temperature operation, which prevents seizing even when they cool quickly.
  • Virtually maintenance-free operations: Relubrication of the bearings is not necessary because they are lubricated for life.
  • Excellent performance in hot, dry, and low-speed application
  • Reduce environmental impact
  • Reduce machine design complexity. 

Lubrication solution

Several graphite-based lubrication techniques are used in NBC Bearings’ high-temperature bearing designs and variations, including:
  1. Lubricating paste composed of a graphite mixture
  2. Graphite cages
The graphite keeps a fragile film on the rolling components and raceways of the bearing while it is in use, thus reducing wear. The necessity for relubrication is eliminated since graphite loses its lubricating capabilities at a considerably higher temperature than oil and grease and ages at a much higher temperature than those materials. All of the bearing’s surfaces, including any applicable shields and flingers, are manganese phosphate coated in various forms to increase the lubricant’s adherence to the metal, enhance the running-in characteristics, and offer some corrosion protection.

Application

  1. StructuralFood processing
  2. Pulp and paper
  3. Steel Mills
  4. Mining
  5. Heavy Machinery
  6. Metal Plating
  7. Medical Equipment
  8. Marines
  9. Offshore
  10. Aerospace