To select a bearing for food processing equipment, work through six decisions in order: the washdown zone the bearing sits in, the cleaning chemistry it meets, the ring and ball material, the seal and cage, the lubricant, and finally the life calculation. Do it in that order and the part number falls out of the answers. Do it backwards, starting from a standard bearing and asking whether it is “food grade”, and the answer will always be vague.

That sequence is why a general bearing catalogue is a starting point rather than a specification. A 6203 with two rubber seals is 17 mm bore, 40 mm outside diameter and 12 mm wide, weighs about 0.06 kg, and is one of the most widely produced bearings in the world. The same envelope can be built in several materials and greases, and which one you need depends on where the machine is washed, not on the catalogue page.

Does the FDA approve bearings?

No. The FDA regulates food-contact substances and food additives, and it does not issue an approval for a bearing as a product. What exists instead is a framework: the materials that touch food must comply with the applicable regulations, and the lubricant must comply with 21 CFR 178.3570 if it can contact food incidentally.

Because the regulation is written around substances rather than products, so a supplier’s declaration of compliance is the document that matters, not a logo on the box. Ask for the material declaration for the rings, balls, cage and seals, and a separate statement for the grease with its H1 registration reference.

The seal material has its own rule. Rubber articles used repeatedly in contact with food fall under 21 CFR 177.2600, which is why a food-grade bearing question usually ends up as two questions: what is the grease, and what are the seals made of.

Mapping the washdown zone

Four zones, and each one changes the specification. A dry zone sees flour dust and ambient humidity. A splash zone sees spillage and a hose at low pressure. A washdown zone sees detergent, hot water and a directed jet. A clean-in-place or caustic zone sees hot alkali or acid circulation, which is the most aggressive of the four.

Because the cleaning chemistry drives corrosion faster than the duty cycle drives fatigue, so the zone should be written on the drawing before the bearing is chosen. Two identical conveyors in the same plant can need different bearings if one is hosed down nightly and the other is wiped.

Write the zone on the drawing as a word rather than a code, so the buyer, the maintenance fitter and the auditor read the same requirement. Zone also sets the ingress protection target. A splash zone is satisfied by a sealed bearing in a shielded housing. A washdown zone needs a sealed bearing plus a housing that sheds water and does not trap it, and a caustic zone needs the material change described below before any seal upgrade helps.

Which material suits which zone?

Chrome steel for dry zones, 440C stainless for splash and light washdown, 316 stainless or a hybrid ceramic for heavy washdown and caustic, and polymer or ceramic for the most aggressive chemical duty. The table is the short version we use in a selection review.

Because 440C is a martensitic stainless rather than a corrosion-proof alloy, so it is the right answer for a splash zone and the wrong answer for a caustic washdown line. A hybrid bearing with ceramic balls and stainless rings is often the practical compromise where the duty is wet, fast and lightly loaded.

Polymer and ceramic bearings deserve a mention for the harshest positions, such as a roller in a brine or acid environment where even 316 will not last. They trade load capacity for chemical resistance, so they belong where the load is low and the cleaning is relentless.

What do seals and grease contribute to life?

More than most buyers expect. A sealed bearing keeps the H1 grease in and the wash water out, and the seal material has to survive both the detergent and the temperature. Nitrile is adequate for cool splash zones, FKM is the usual choice for higher temperatures and aggressive chemistry, and EPDM suits caustic and steam but dislikes mineral oils.

The grease is the other half. An H1 lubricant is registered for incidental food contact, and its registration reference should appear on the specification. Because washdown water eventually reaches every seal lip, so the grease must tolerate a little water without emulsifying into a paste that starves the balls.

Temperature is the second constraint. A washdown line rarely exceeds 60–80 °C at the bearing, but a sterilisation cycle or a steam lance can push a seal past its limit, and FKM holds to roughly 200 °C where nitrile is comfortable only to about 100 °C.

Housing design decides whether the seal has a chance. A bearing pocket that fills with water and cannot drain will kill a sealed bearing through the outside of the outer ring, and no grease specification prevents that. Drill the housing to drain, face the seal away from the jet where the geometry allows, and check the position after the first washdown rather than at commissioning.

How do you size the bearing without over-specifying?

Calculate the L10 life from the dynamic load rating and the actual radial load, then derate for the material. For a ball bearing, L10 is the rating divided by the equivalent load, cubed, multiplied by one million revolutions. Because stainless rings carry less load than chrome steel at the same envelope, so a life calculation carried over from a chrome steel part will overstate a 440C or 316 replacement by 20–30%.

A 6203 in chrome steel is rated at roughly 10 kN dynamic, and the stainless versions of the same envelope are typically in the 7–8 kN range depending on grade and maker. If the application was already close to its limit on chrome steel, the stainless substitution is a redesign rather than a drop-in.

Then check three details that get missed: clearance, fits and speed. A C3 clearance is normal for a bearing that runs warm, a light interference fit on the shaft and a push fit in the housing suit most food equipment drives, and a sealed bearing has a lower speed limit than the open version because the seal generates heat. Take the speed limit from the supplier’s data for the sealed variant, not from the open bearing catalogue. Fits deserve their own line on a replacement part: a worn shaft that has lost its interference will spin the inner ring whatever the ring material, so measure the shaft before ordering a stainless replacement and put the housing tolerance on the same drawing.

What belongs in a food-grade bearing RFQ?

Six items, and a quotation without them is a price rather than an offer.

• Zone and chemistry: dry, splash, washdown or CIP, with the detergent type and concentration range.
• Material declaration: ring, ball, cage and seal materials, with the CFR reference for the seal compound.
• Lubricant statement: H1 registration reference, base oil type, temperature range and fill quantity.
• Seal and shield configuration: 2RS contact seal, non-contact shield, or labyrinth, with the ingress protection target stated.
• Life and load data: dynamic and static ratings, the derating applied for the stainless grade, and the sealed speed limit.
• Traceability: batch marking, heat number on request, and the inspection record for the lot.

Add the mounting details too, because a food equipment bearing is usually replaced in situ: bore and outside diameter tolerances, the housing material, and whether the replacement has to match an existing shaft that is already worn.

The standard 6203 as a reference envelope

The 6203 fits as the reference envelope, not as the food-grade answer. The 6203 2RS is 17 × 40 × 12 mm, about 0.06 kg, available in P0, P6 and P5 precision with C0, C2 or C3 clearance — the sort of part that fills a motorcycle, pump or fan application where the environment is dry and the load is predictable.

Because the dimensions are standard, so the same envelope can be supplied in a different material and grease for a food line — but only if the drawing asks for it. Ordering “6203 2RS” for a washdown conveyor gets you the chrome steel part with a general-purpose grease, which is exactly the combination that fails first.

The China bearing factory catalogue shows the envelope range we produce, including deep groove ball bearings, ceramic and hybrid series and track rollers, and the 6203 2RS page is the reference for that size. Whether a given size can be built in 440C or 316 for your duty is a question to put to the factory with the drawing, not an assumption to carry into a purchase order.

Where this guidance stops

This is a selection framework, not a compliance certificate. Whether a specific bearing is acceptable in a specific food contact position is a decision for your hygiene engineer, your customer’s audit and, where 3-A or EHEDG design rules apply, the certifying body. The 3-A Sanitary Standards organisation publishes the design requirements for cleanable equipment, and those requirements cover the housing and the mounting as much as the bearing.

What a bearing supplier can do is give you the material declarations, the grease registration, the load ratings and the life calculation in writing, and build the part to the drawing. Send the zone, the chemistry and the load through the bearing quote request and we will come back with a specification rather than a part number.

Frequently asked questions

Is there such a thing as an FDA approved bearing?

No. The FDA regulates food-contact substances rather than approving finished bearings, so compliance is demonstrated through material declarations and a compliant lubricant. A supplier who claims an FDA approval for a bearing is usually describing materials compliance, and you should ask for the documents behind the claim.

Can I use a standard 6203 2RS in a food plant?

Only in a dry or enclosed position where the bearing does not meet wash water or cleaning chemicals. In a washdown zone the same 17 × 40 × 12 mm envelope needs a stainless or hybrid build and an H1 grease, and the housing needs to drain.

Is 440C stainless good enough for washdown?

It is good for splash and light washdown, and it is not the best choice for caustic or chloride-rich cleaning because it pits. Where the cleaning is aggressive, 316 rings or a hybrid ceramic bearing last longer, at the cost of load capacity and price.

What does H1 mean on a bearing grease?

H1 identifies a lubricant registered for incidental food contact, which is the category described in 21 CFR 178.3570. The registration is held by the lubricant maker, so the bearing specification should quote the registration reference rather than the word “food grade”.

How much load capacity do I lose going to stainless?

Expect roughly 20–30% less dynamic capacity than the chrome steel equivalent for 440C, and more again for 316. If the original application had little margin, the stainless substitution changes the life calculation and may change the bearing size.

Do sealed bearings run slower?

Yes. A contact seal adds friction and heat, so the sealed version of a bearing has a lower speed limit than the open or shielded version. Take the limit from the sealed variant’s data sheet, especially on a high-speed food equipment drive.