The food and beverage industry can involve fairly harsh environmental operating conditions. This can come from spillage of a processed beverage or immersion in food product. However, frequent wash down, using high pressure and high temperature cleaning solutions involving sanitizing chemicals, can be an even greater source for potential degradation of the bearing performance. In Food & Beverage applications, typically bearing performance is defined by two characteristics: external corrosion resistance and rotational bearing life. In some applications, the external appearance alone decides when a bearing requires replacement. Visual evidence of corrosion can be seen by inspectors as a potential for contamination of adjacent food/beverage product, or as a sign of impending end of life for rotational performance. In other applications, more emphasis is placed on bearing operating life, such that the user wishes to achieve longest operating time of the bearing, and minimize loss of production due to unexpected bearing breakdown.
In this paper, we will address Sealmaster and Browning CRES (Corrosion Resistant Engineered Solutions) mounted ball and roller bearings’ features and benefits, and how they provide solutions that promote the performance needs in the food and beverage industry applications.
Regal Rexnord offers varying solution levels to balance the needs of the application and budget.
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Mounted Ball |
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Bearing Insert |
Housing |
Seal |
Shaft Size |
End Cap |
Shield |
IP69K |
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Sealmaster SS Gold™ |
440C |
300 series Stainless Steel |
High Performance triple lip, FKM |
3/4 – 1 ½” |
Yes |
Yes |
Yes |
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Sealmaster PN Gold™ |
High Phosphorus Nickel coating |
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High Performance triple lip, FKM |
3/4 - 2 7/16” 20 – 60 mm |
Yes |
Yes |
Yes |
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Browning® CRES SS |
440C |
300 series Stainless Steel |
Single lip nitrile rubber |
3/4 – 1 ½” |
Yes |
No |
No |
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Mounted Roller |
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Sealmaster PN Gold™ Spherical Roller |
High Phosphorus Nickel coating |
Fluoropolymer coated cast iron |
Double Lip, FKM |
1 15/16 – 7 15/16” |
No |
No |
Yes |
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Sealmaster RPB-CR Tapered Roller |
Bearing Steel |
Fluoropolymer coated cast iron |
Single lip, nitrile rubber |
1 3/16 – 5” 35 – 125mm |
No |
No |
Yes |
Sealmaster SS Gold mounted ball bearings builds off many features as found in PN Gold, into an all stainless steel construction bearing assembly, for those applications where a coating or plating is either not preferred or allowed. This series incorporates the same high performance multi-lip seal, and is available in setscrew locking type in a variety of stainless steel housing configurations.
Sealmaster PN Gold™ mounted ball bearings feature high phosphorus electroless nickel coated steel bearing inserts combined with a high performance multi-lip seal, providing strong resistance to corrosion and contamination. Available with setscrew or SKWEZLOC™ concentric locking collar, and within a variety of stainless steel, composite, and fluoropolymer coated housing configurations.
Sealmaster self-aligning high capacity tapered roller bearings include fluoropolymer coated housings and lock collar, and single lip contact seal. This IP69K certified product is suited for heavier loading conditions in wet environments where there are heavy loads.
Sealmaster PN Gold mounted spherical roller bearings are an industry first for a fully corrosion resistant mounted roller bearing. This IP69K certified product applies features including: high phosphorus nickel coating to bearing rings, fluoropolymer coated housings and lock collar, and double lip seals with stainless steel casing. These combined features offer our best solution for a corrosion resistant bearing capable of supporting heavy loading as well as static/dynamic misalignment.
Browning provides a basic level of protection for wash down environments. Comprised of stainless steel housings and ball bearing inserts, one can meet most corrosion resistance needs. A rubber lip seal combined with flinger shield provides good balance to grease retention and contaminant resistance.
Composite material housings are an option within the Sealmaster PN Gold offering. This option provides an economical balance between corrosion and cleanliness needs for those applications that may be less harsh, or that support lower loads or duty cycles.
Xylan® fluoropolymer coating applied to cast iron housings, is used for Sealmaster RPB-CR, USRB PN Gold and certain PN Gold Ball units, as well as concentric locking collars. The coating is multilayered, as detailed below, resulting in a strong bonded coating providing a non-stick type surface resilient to wear and corrosion. The Xylan coating is far more resistant in wash down as well as acid and base solution environments, as compared to conventional painted, plated or Teflon* type coatings.
| Characteristic | Sealmaster Corrosion Duty |
Paint | Electroless Nickel | Teflon®* |
| Acid Resistance | ✔✔✔✔ | ✔ | ✔✔✔ | ✔✔✔✔ |
| Base Resistance | ✔✔✔✔ | ✔ | ✔✔ | ✔✔✔✔ |
| Washdown | ✔✔✔✔ | ✔ | ✔✔ | ✔** |
| General Exposure | ✔✔✔✔ | ✔✔ | ✔✔ | ✔✔✔✔ |
| Non-Stick | ✔✔✔✔ | - | - | ✔✔✔✔ |
| Casting Adhesion | ✔✔✔✔ | ✔✔✔ | ✔✔✔ | ✔ |
| Hardness | ✔✔✔ | ✔✔ | ✔✔✔✔ | ✔ |
| Color | ✔✔✔✔ | ✔ | ✔✔ | ✔✔ |
| Excellent ✔✔✔✔ | Fair ✔✔ | Unacceptable - **SHOULD NOT BE USED WITH HIGH PRESSURE SPRAYWASH |
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| Good ✔✔✔ | Poor ✔ | ||
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Investment cast 300 series stainless steel housings:- Smooth finish, easier cleaning. Minimal gaps/entrapment points. |
Sealmaster PN Gold ball and spherical roller mounted product employ a high phosphorus electroless nickel plating onto 52100 bearing quality steel race rings. The result is a high performing corrosion resistant bearing, while maintaining full load rating capability.
400 series stainless steel is applied to race rings and balls in the Sealmaster SS Gold and Browning CRES SS mounted ball product. 400 series stainless steel provides both corrosion resistance as well as hardening capability so as to support rolling contact stresses and resist wear. The choice of a stainless steel bearing is important to certain users who must avoid any contamination risk due to potential flaking of a coating or plating.
The corrosion resistance characteristics of coatings and stainless steel solutions versus other options is likewise demonstrated below. Here we see side by side test results in which parts were exposed to acidic solutions (e.g. food/beverage processing), as well as base solutions (e.g. cleaning solutions).
Wet Box Acid Spray Test:Outer rings sprayed with Citric Acid (pH 2) for 8 hours
Wet Box Bleach Spray Test: Outer rings sprayed with 6% bleach solution (pH 12) for 8 hours.
Beyond the effects of corrosion to visual appearance, corrosion also affects the ability of the bearing to perform its function of rotational operation. Corrosion can lead to degradation of the seals, resulting in contaminant ingress or internal component wear leading to bearing seizure. Having applied the solutions discussed prior regarding materials or coatings to protect against corrosion, the next key solutions provided by Sealmaster and Browning product is a seal design that brings together protection against contaminants and lubricant retention so as to promote long rotational life in harsh wet and corrosive environments.
Sealmaster PN Gold and SS Gold mounted ball bearings utilize an HPS high performance seal. The features of this seal, as detailed below, provide a multiple and multi-directional sealing system working in conjunction with the outside flinger and grease cavities that can perform in chemical and corrosive environments while maintaining good speed and drag characteristics.
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1.Triple Lip FKM Fluoro-Elastomer, with Axial Riding Lip 2.Integrated 300 Series Stainless Steel Flinger. 3.300 Series Stainless Steel Inside Seal Stamping. 4.Cavities Packed With GoldPlex-FG Grease. |
Browning CRES SS employs a base level of protection and retention capabilities. A nitrile rubber lip seal is combined with an outboard stainless steel flinger. This seal arrangement is better suited for less harsh environments, such as where there may be incidental splash or indirect spray. The stainless steel flinger attached to the inner ring acts as a2 rotating shield, to “fling” away contamination that may contact it.
The effectiveness of this seal design is demonstrated in a slurry box test. The test is purposely harsh so as to determine the resilience of the seal in a short time period. The test bearing is submerged in a slurry mixture of water and fine particulate. The test time is determined by when the slurry is found to pass through the bearing. Many seal types offered in the mounted bearing industry have been subjected to this test, and the Sealmaster HPS has outperformed all others to date.
Note – The reference to or listing of competitors is not intended to be complete or comprehensive and is intended to identify, for discussion, examples of companies offering some competitive product and/or services. Source of information is from internal testing.
Sealmaster mounted roller bearings use a race mounted contacting lip seal design. Having the seals integral to the bearing insert assembly, as opposed to externally mounted within the bearing housing, enables the seal arrangements to operate effectively within he misalignment capability of the bearing.
The RPB tapered roller bearing product uses a single lip style design and the USRB spherical roller product uses a double lip style design.
RPB Tapered Roller Bearing Contact Seal 
USRB Spherical Roller Bearing Contact Seal An industry standard was established so as to identify a products capability to withstand ingress of water and/or dust, with testing performed by an independent and certified lab. This testing and certification is used by many manufacturers of electronics and power transmission products today, particularly for items designed to operate in harsh environments.
There are various levels of protection as identified by the certification. Below is an outline of the certification and meaning of code:
IP69K represents the highest level of resistance to this test, demonstrating that the product is resistance to ingress of dust and high pressure/high temperature water spray. This certification further endorses the effectiveness of the various sealing designs as incorporated in Sealmaster mounted ball and roller bearings for the food and beverage industry.
8 hours, vacuum applied through bearing to evaluate dust ingress. 
8 minutes, 4 GPM spray at 1160 – 1450 PSI, 4-6” distance, 176F water, 2 minutes x 4 angles. Regal Rexnord provides differentiated solutions to food and beverage industry users of mounted ball and roller bearings. An array of options are available under Sealmaster, each offering features that help the user achieve their goals, whether it is visual cleanliness, operational performance, or a combination of both.
The proper selection and application of products and components, including assuring that the product is safe for its intended use, are the responsibility of the customer. To view our Application Considerations, please visit https://www.regalrexnord.com/Application-Considerations. To view our Standard Terms and Conditions of Sale, please visit https://www.regalrexnord.com/Terms-and-Condi-tions-of-Sale (which may redirect to other website locations based on product family).
* The following are believed to be the trademarks and/or trade names of their respective owners and are not owned or controlled by Regal Rexnord Corporation. Teflon: The Chemours Company FC, LLC; Xylan: Whitford Corporation“Regal Rexnord” is not indicative of legal entity. Refer to product purchase documentation for the applicable legal entity.Regal Rexnord PN Gold, Sealmaster and USRB are trademarks of Regal Rexnord Corporation or one of its affiliated companies.© 2023 Regal Rexnord Corporation, All Rights Reserved.
