Precision Steel Ball FAQsGrade Standards, Certifications & Global Export

Rama & Sons manufactures precision steel balls to all major international standards: ISO 3290-1 (international), ABMA Standard 10 (USA), DIN 5401 (Germany/Europe), and JIS B 1501 (Japan). We cross-reference all alloy grades using AISI (USA), DIN/EN (Europe), JIS (Japan), and BIS (India) standards. Every order comes with documentation showing the exact standard requested in your purchase order.

Sphericity measures how close a ball is to a perfect sphere. For a G10 ball, it varies by less than 0.25 microns, which keeps high-speed bearings running quietly without vibration. Surface finish (Ra) measures the smoothness of the ball surface. A lower Ra number means less friction, lower operating temperature, less wear, and a longer bearing life.

EN-31 and AISI 52100 (also known as 100Cr6 in Germany and SUJ2 in Japan) are simply different regional names for the same high-carbon chrome bearing steel. Both have ~1% Carbon and ~1.5% Chrome, harden to 60–66 HRC, and offer exceptional wear resistance and long fatigue life. They are completely interchangeable. You can browse our Chrome Steel bearing balls on the Products page.

SS 304 is a good general-purpose stainless steel with basic rust resistance. SS 316 adds Molybdenum, making it far more resistant to salt water, acids, and harsh chemicals. SS 440C is a hardened stainless steel (56–60 HRC) that gives you both high hardness and rust resistance — making it the top choice for stainless bearings and high-pressure check valves. You can compare all material properties in our Materials Matrix on the homepage.

We manufacture precision spheres in high-performance specialty superalloys: Inconel 625 & 718 (for extreme temperatures up to 980°C in jet engines and turbine valves), Monel K-500 (for subsea wellheads, offshore check valves, and rapid seawater flow), Stellite 6 (cobalt-chromium alloy for severe cavitation and abrasive slurry), Hastelloy C-276 (for strong oxidizing acids and wet chlorine gas), and Tungsten Carbide WC-Co (for extreme hardness approx. 90 HRA / 1500 HV in downhole drilling and flowmeters). Small prototype batches and custom diameters are supported.

Yes! We specialize in supporting R&D laboratories, prototype valve designers, and precision engineering teams with small test quantities (10 to 50 pieces) without requiring multi-ton minimum orders. Every prototype batch is precision lapped to your exact drawing and shipped with an EN 10204 3.1 chemical and dimensional test certificate. When your testing qualifies, we scale directly to full production volumes.

Yes. We supply pre-production qualification samples (typically 10 to 50 pieces per size) for your testing and quality approval. Samples ship in 3 to 5 business days and come with a full dimensional inspection report and material test certificate. Once your engineering team approves the samples, we start your main production order.

We manufacture a complete range of vibratory and barrel finishing media: Stainless Steel Cut Wire Shots (0.3mm to 2.0mm), Cross Pins, Straight Pins, Rava (disc ball) media, Damru-shaped media, and Saturn-shaped media — in both SS 304 and SS 316. We also supply Zinc Cut Wire Shots for soft metal polishing. These are widely used for deburring jewelry, automotive die-cast parts, and surgical instruments. Browse our Polish Media catalog.

We ship through ICD Delhi, Mundra Port (Gujarat), and Nhava Sheva / JNPT (Mumbai). Standard catalog sizes ship in 3 to 5 business days from ready stock. Custom sizes or special alloys take 15 to 25 business days to manufacture. We also offer air freight for urgent sample orders. We provide complete shipping paperwork, including Bill of Lading, packing list, and Certificate of Origin.

Rama & Sons exports to customers in 30+ countries across North America (USA, Canada, Mexico), Europe (Germany, UK, Italy, Netherlands), the Middle East (UAE, Saudi Arabia), Southeast Asia, and Africa. We provide express international air dispatch (DHL / FedEx / Air Freight) for urgent test prototypes, and consolidated ocean container shipments for high-volume supply contracts.

For standard stock sizes in EN-31, SS 304, and SS 316, our MOQ is just 1 kg for trial orders and testing. For custom decimal sizes or exotic superalloys (Inconel, Monel, Stellite, Tungsten Carbide), we can provide small prototype batches (such as 10 to 50 pieces) or production volumes based on your requirements. For stainless cut wire shots, the MOQ is 50 kg.

You can request a quote by using the RFQ Configurator on our homepage, filling out the form on our Contact page, or emailing us directly at sales@ramason.in or info@ramason.in. We reply to all inquiries within 24 business hours with prices, lead times, and full technical specifications.