{"product_id":"304-stainless-steel-ball-bearings-31-75mm-40mm-precision-steel-ball","title":"31.75mm to 40mm Solid 304 Stainless Steel Ball Bearings Precision Steel Ball","description":"\u003cdiv class=\"hdiy-desc\"\u003e\n\u003cdiv class=\"hdiy-overview\"\u003e\n\u003ch2\u003e304 Stainless Steel Precision Ball Bearings — Solid Rolling Elements for Demanding Applications\u003c\/h2\u003e\n\u003cp\u003eWhen a worn or undersized ball causes vibration, noise, or premature bearing failure, the fix starts with sourcing a dimensionally accurate replacement. Engineers, maintenance technicians, and serious DIYers who work with valves, pumps, linear slides, or custom bearing assemblies need rolling elements they can trust to hold tolerance across repeated load cycles.\u003c\/p\u003e\n\u003cp\u003eThese solid 304 stainless steel ball bearings are available in eight diameters ranging from 31.75 mm (1-1\/4 in) to 40 mm (approximately 1-37\/64 in). Each ball is machined from 304-grade stainless steel — an austenitic alloy that combines moderate hardness with strong resistance to oxidation and mild corrosion. Sold individually or in packs of five, they suit both single-replacement jobs and small-batch assembly work.\u003c\/p\u003e\n\u003cp\u003eTypical use cases include replacement rolling elements in industrial ball-bearing housings, check-ball seats in hydraulic and pneumatic valves, load-distributing balls in custom linear or rotary fixtures, and decorative or functional hardware in furniture and architectural fittings. The 38.1 mm (1-1\/2 in) and 40 mm sizes are particularly common in heavy-duty valve and pump applications where a larger contact surface is required.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-compat\"\u003e\n\u003cspan class=\"hdiy-compat-icon\"\u003e⚙️\u003c\/span\u003e \u003cstrong\u003eCompatibility note:\u003c\/strong\u003e Verify the bore diameter of your housing or seat before ordering. These balls are solid and non-hollow; they are not intended for use as bearing races or cage assemblies. Select the size that matches your application's nominal ball diameter.\u003c\/div\u003e\n\u003cdiv class=\"hdiy-features\"\u003e\n\u003ch2\u003e✅ Key Features of These 304 Stainless Steel Precision Ball Bearings\u003c\/h2\u003e\n\u003cul class=\"hdiy-list\"\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🔩\u003c\/span\u003e\u003cstrong\u003eSolid 304 Stainless Steel Construction\u003c\/strong\u003e — Machined from a single piece of 304-grade austenitic stainless steel for uniform density and consistent load distribution throughout the ball.\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e📏\u003c\/span\u003e\u003cstrong\u003eEight Diameter Options (31.75 mm – 40 mm)\u003c\/strong\u003e — Covers the most common large-ball sizes in metric and fractional inch standards, from 31.75 mm (1-1\/4 in) up to 40 mm (approximately 1-37\/64 in).\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🛡️\u003c\/span\u003e\u003cstrong\u003eCorrosion-Resistant Alloy\u003c\/strong\u003e — 304 stainless steel provides reliable resistance to moisture, mild acids, and atmospheric oxidation, making these balls suitable for damp or lightly corrosive environments.\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🎯\u003c\/span\u003e\u003cstrong\u003eTight Spherical Tolerance\u003c\/strong\u003e — Manufactured to close roundness tolerances to minimize runout and vibration when used as rolling or seating elements in precision assemblies.\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e📦\u003c\/span\u003e\u003cstrong\u003eSingle or 5-Pack Quantity Options\u003c\/strong\u003e — Order one ball for a direct replacement or a pack of five for batch assembly, prototyping, or stocking a maintenance kit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan class=\"hdiy-icon\"\u003e🔄\u003c\/span\u003e\u003cstrong\u003eBroad Application Range\u003c\/strong\u003e — Suited for valve check seats, pump internals, linear bearing assemblies, custom fixtures, and decorative hardware requiring a large-diameter stainless ball.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-table-wrap\"\u003e\n\u003ch2\u003e📐 Technical Specifications — Stainless Steel Precision Ball Bearings\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003e304 Stainless Steel (austenitic)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eBall Type\u003c\/th\u003e\n\u003ctd\u003eSolid, one-piece\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eAvailable Diameters\u003c\/th\u003e\n\u003ctd\u003e31.75 mm \/ 32 mm \/ 34 mm \/ 35 mm \/ 36 mm \/ 38.1 mm \/ 39 mm \/ 40 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eDiameter Range (inch equiv.)\u003c\/th\u003e\n\u003ctd\u003eapprox. 1-1\/4 in – 1-37\/64 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSurface Finish\u003c\/th\u003e\n\u003ctd\u003eSmooth, bright-rolled stainless\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHardness\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eGrade \/ Tolerance Class\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eQuantity per Order\u003c\/th\u003e\n\u003ctd\u003e1 pc or 5 pcs (select above)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWeight (per ball)\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eApplication\u003c\/th\u003e\n\u003ctd\u003eValves, pumps, linear slides, custom bearing assemblies, decorative hardware\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq\"\u003e\n\u003ch2\u003e❓ Frequently Asked Questions\u003c\/h2\u003e\n\u003cdetails\u003e\n\u003csummary\u003eHow do I choose the right ball diameter for my application?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eMeasure the bore or seat diameter of your housing with a caliper. The ball should match the nominal diameter specified in your assembly drawing or the diameter of the ball you are replacing. For valve check seats, the ball diameter is typically slightly larger than the seat orifice to ensure a positive seal — consult your valve's service manual for the exact specification.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhat is the load capacity of these balls?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eLoad capacity depends on the specific application geometry, contact angle, and surface hardness of the mating parts. 304 stainless steel has a typical hardness of around 70–90 HRB, which is lower than hardened chrome steel (52100) bearing balls. These balls are well-suited for moderate-load applications such as valve seats and light-duty linear guides. For high-load or high-speed bearing assemblies, contact us to confirm suitability.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eAre these balls corrosion-resistant enough for outdoor or wet environments?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003e304 stainless steel offers good resistance to atmospheric moisture, fresh water, and mild chemical exposure. It is not recommended for prolonged immersion in chloride-rich environments (such as seawater or pool water) where 316 stainless steel would be a better choice. For most indoor industrial, plumbing, and light outdoor applications, 304 is a reliable option.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eCan these balls be used as replacement rolling elements in a standard ball bearing race?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eYes, provided the diameter matches the original ball size in the bearing. Remove the retainer cage, replace worn balls with new ones of the same diameter, and reassemble. Note that 304 stainless is softer than the hardened steel typically used in precision bearing balls (Grade 10–25); if your application demands tight ABEC-rated tolerances or very high RPM, verify the grade requirement with your bearing manufacturer before substituting.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhat is the difference between the 31.75 mm and 32 mm sizes?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003e31.75 mm is the metric equivalent of 1-1\/4 inches (a fractional inch standard common in North American equipment), while 32 mm is a true metric size used in ISO-standard assemblies. They differ by 0.25 mm — enough to cause a loose fit if the wrong size is installed. Always confirm whether your application uses inch-based or metric dimensioning before selecting.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eIs the 5-pack a better value than buying individual balls?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eThe 5-pack price per ball is lower than the single-unit price across all sizes, making it the more economical choice if you need multiple balls for a batch assembly, want spares on hand for future maintenance, or are building a custom fixture that requires several rolling elements of the same diameter.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eCan I use these balls in food-processing or pharmaceutical equipment?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003e304 stainless steel is widely used in food-contact applications and meets general FDA material guidelines for stainless steel. However, suitability depends on your specific regulatory requirements and the cleaning chemicals used in your process. Contact us to confirm compliance documentation if your application requires formal certification.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-cta\"\u003e🛒 Select your Size and QTY above, then add to cart.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"HomeDIYer","offers":[{"title":"31.75mm \/ 1","offer_id":52410088849682,"sku":"LQHJSSYX0048x1","price":12.66,"currency_code":"USD","in_stock":true},{"title":"32mm \/ 1","offer_id":52410088882450,"sku":"LQHJSSYX0049x1","price":12.84,"currency_code":"USD","in_stock":true},{"title":"34mm \/ 1","offer_id":52410088915218,"sku":"LQHJSSYX0050x1","price":16.44,"currency_code":"USD","in_stock":true},{"title":"35mm \/ 1","offer_id":52410088947986,"sku":"LQHJSSYX0051x1","price":17.26,"currency_code":"USD","in_stock":true},{"title":"36mm \/ 1","offer_id":52410088980754,"sku":"LQHJSSYX0052x1","price":18.66,"currency_code":"USD","in_stock":true},{"title":"38.1mm \/ 1","offer_id":52410089013522,"sku":"LQHJSSYX0053x1","price":21.69,"currency_code":"USD","in_stock":true},{"title":"39mm \/ 1","offer_id":52410089046290,"sku":"LQHJSSYX0054x1","price":24.19,"currency_code":"USD","in_stock":true},{"title":"40mm \/ 1","offer_id":52410089079058,"sku":"LQHJSSYX0055x1","price":25.8,"currency_code":"USD","in_stock":true},{"title":"31.75mm \/ 5","offer_id":52410089111826,"sku":"LQHJSSYX0048x5","price":58.86,"currency_code":"USD","in_stock":true},{"title":"32mm \/ 5","offer_id":52410089144594,"sku":"LQHJSSYX0049x5","price":59.73,"currency_code":"USD","in_stock":true},{"title":"34mm \/ 5","offer_id":52410089177362,"sku":"LQHJSSYX0050x5","price":77.79,"currency_code":"USD","in_stock":true},{"title":"35mm \/ 5","offer_id":52410089210130,"sku":"LQHJSSYX0051x5","price":81.87,"currency_code":"USD","in_stock":true},{"title":"36mm \/ 5","offer_id":52410089242898,"sku":"LQHJSSYX0052x5","price":88.84,"currency_code":"USD","in_stock":true},{"title":"38.1mm \/ 5","offer_id":52410089275666,"sku":"LQHJSSYX0053x5","price":104.01,"currency_code":"USD","in_stock":true},{"title":"39mm \/ 5","offer_id":52410089308434,"sku":"LQHJSSYX0054x5","price":116.55,"currency_code":"USD","in_stock":true},{"title":"40mm \/ 5","offer_id":52410089341202,"sku":"LQHJSSYX0055x5","price":124.54,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Picture6of7_524063c5-3a8e-400d-812a-edbfdb042415.jpg?v=1782373532","url":"https:\/\/homediyer.com\/products\/304-stainless-steel-ball-bearings-31-75mm-40mm-precision-steel-ball","provider":"HomeDIYer","version":"1.0","type":"link"}