420/420C Stainless Ball

How We Manufacture Premium 420/420C Stainless Steel Balls

Cold Heading

We begin with premium-grade AISI 420 wire. The wire is cut to precise lengths and forged into rough 420 stainless steel spheres between two hemispherical dies under immense pressure.
Our heavy-duty cold-heading machinery ensures continuous, high-volume production without compromising the structural density of the martensitic steel. This guarantees consistent mechanical properties across large wholesale orders.

Soft Grinding

The newly forged, unhardened 420 steel balls are rolled between heavy cast-iron plates under high pressure. This step removes the "equator" seam (flashing) created during cold heading.
Soft grinding improves the initial sphericity of the AISI 420 balls and relieves internal surface stresses, creating a perfectly uniform foundation before the critical heat treatment and hardening phase.

Heat Treatment

The heat treatment of the shaft steel ball is to raise the temperature in the furnace to 1000-1050 ℃, the heat preservation time is 30-60 minutes, and the tempering furnace to 145-155 ℃,the heat preservation time is 40-90 minutes.During the heat treatment process, the hardness, vulcanization, Metallographic structure and crushing load are clearly defined.

Hard Grinding

The now-hardened magnetic 420 stainless balls undergo intense grinding using specialized abrasive ceramic wheels. This process removes any decarburized surface layers left by the heat treatment.
This is where raw material becomes a precision component. We grind our high-hardness steel balls down to exact micrometer tolerances, easily achieving precision grades from G10 to G100 based on your engineering requirements.

Polish Steel Balls

Polishing ball process is to initially polish the ball blank into a circle. It's a very important process.

Oil Removal & Cleaning

We pass the polished 420C stainless balls through automated ultrasonic cleaning lines using eco-friendly, industrial-grade solvents to strip away all polishing compounds and residual machining oils.
We deliver 100% residue-free products. Cleanliness is paramount for buyers integrating our stainless steel spheres into sensitive pneumatic valves, food-processing machinery, or measuring instruments.

Screening & Sorting

Because 420 stainless steel balls are magnetic, they are carefully separated and passed through precision roller-sorting machines and automated optical inspection systems.This guarantees zero defects. We strictly sort out any out-of-round pieces, microscopic surface scratches, or size variations, ensuring every wholesale 420 stainless steel ball you receive is dimensionally identical.

Measuring Instrumentation

In our state-of-the-art laboratory, QA engineers use high-end measuring instrumentation—including roundness testers, surface roughness meters, and Rockwell hardness testers—to validate every batch of AISI 420 spheres.Data-backed reliability. We supply comprehensive Material Test Reports (MTR) and Certificates of Conformance (CoC) with every shipment, proving that your custom 420 steel balls perfectly match the requested chemical composition, hardness, and precision grade.

Features of  420/420C Stainless Steel Balls

Our Factory

Changzhou Risheng Steel Ball Co., Ltd. is located on the eastern shore of Taihu Lake, adjacent to Shanghai, with convenient transportation. Since its establishment in June 1995, the company has been dedicated to developing and manufacturing steel balls, integrating research and development with trade.

For many years, Risheng building on the foundation of the Wujin Metal Ball Research Institute, has been committed to researching steel ball manufacturing technology. We primarily produce shaft steel balls (AISI 52100), stainless steel balls (AISI 201/304/316/420/440/430), and carbon steel balls (AISI 1015/1045/1085) with diameters ranging from 0.8mm to 25.4mm, with precision grades up to G10, G40, and G100. We also offer custom specifications for alloy steel balls, military steel balls, copper balls, UFO balls, ceramic balls, and other metal balls. 

Packaging & Deliver of 420/420C Stainless Steel Ball

High-strength inner packaging: Shockproof foam bags or custom plastic boxes are used to secure each 420/420C stainless steel ball in place, protecting it from impacts and scratches.

Moisture-proof protection: A moisture-proofing agent is added to effectively prevent the impact of moisture on the product during transportation.

Sturdy outer packaging: Thickened corrugated cardboard boxes or wooden pallets (for large orders) are used to ensure safe long-distance transportation.

Clear labeling: Product specifications, quantity, and drop warnings are clearly marked on the outer packaging box for easy verification and safe handling.

Service Process