Question 1

What are Stellite balls made of?

Accepted Answer

Stellite balls are made from cobalt-chromium-tungsten (Co-Cr-W) alloys, often with additions of molybdenum, nickel and carbon. The cobalt matrix is reinforced with hard carbides, giving the balls exceptional wear, heat and corrosion resistance compared with ordinary steel.

Question 2

What is the difference between Stellite 6 and Stellite 20 balls?

Accepted Answer

Stellite 6 offers the best combination of wear resistance and toughness, making it the most widely used grade for valve balls and pump components. Stellite 20 contains more tungsten and carbon, so it is harder (HRC 56–60) and more wear resistant, but also more brittle and harder to machine.

Question 3

What hardness can Stellite balls reach?

Accepted Answer

Depending on grade and processing, Stellite balls typically reach HRC 40–58 for cast grades and HRC 50–62 for powder-metallurgy or work-hardened grades. Stellite 20 can reach HRC 56–60, while Stellite 6 is usually HRC 38–47.

Question 4

Are Stellite balls better than 440C stainless steel balls for valves?

Accepted Answer

For room-temperature hydrocarbon service, 440C (HRC 58–62) is cost-effective. Stellite balls outperform 440C in high temperature, abrasive slurry, severe cavitation or highly corrosive media where heat-softening and corrosion are concerns.

Question 5

What precision grades are available for Stellite balls?

Accepted Answer

Jiaxin supplies Stellite balls in precision grades G10 through G200 per ISO 3290. Valve sealing applications usually specify G16–G40, with G10 available for metal-seated, zero-leak designs.

Question 6

Can Stellite balls be used in high-temperature valves?

Accepted Answer

Yes. Stellite alloys retain hardness and strength well above 500 °C and resist oxidation up to about 800–1000 °C depending on grade, making them ideal for high-temperature steam, exhaust and process valves.

Question 7

What industries use Stellite precision balls?

Accepted Answer

Stellite balls are widely used in oil and gas production (API 11AX pump valves and seats), chemical processing, power generation, marine equipment, aerospace turbochargers, and high-performance industrial valves.

Question 8

Can you supply custom diameters and threaded Stellite balls?

Accepted Answer

Yes. Besides standard diameters from 3 mm to 80 mm, we can produce custom sizes, through-hole balls, internally threaded balls and matched Stellite valve seats to customer drawings.

Question 9

How do you inspect Stellite balls before shipment?

Accepted Answer

Every batch is checked for diameter, roundness, surface roughness, hardness and chemical composition. Valve-ball pairs are vacuum-tested for seal integrity, and full dimensional reports and mill test certificates are available on request.

Question 10

What is the typical lead time and MOQ for Stellite balls?

Accepted Answer

Standard sizes are often available from stock for 7–15 day shipment. Custom diameters and special grades are produced to order with MOQ depending on material and size; samples are available for evaluation.

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