About Haimen City Mingzhu Steel Ball Co., Ltd.
Our core product lineup mainly includes high-quality chrome steel balls and stainless steel balls, all of which are strictly manufactured in accordance with mainstream international standards such as ISO, DIN, JIS and AISI. Our products cover precision grades from G10 to G500, with a complete size range spanning from 2.0mm to 50mm, which can meet the conventional matching needs of most industrial scenarios. In addition to standard products, we also support personalized customized services for customers. We can tailor-make non-standard size steel balls and products with special material properties according to customers’ actual application requirements. Meanwhile, we provide a variety of precision mechanical processing services, including hole drilling, CNC precision machining and other deep processing technologies, to create customized supporting products for diverse industrial needs. Our high-performance steel ball products are widely and maturely applied in numerous fields such as precision bearings, automotive core components, ball screws,
linear slide rails, industrial pumps, spray equipment, and industrial grinding media, enjoying high recognition and good reputation among customers at home and abroad.
Since its establishment more than 30 years ago, our company has always adhered to the core business principle of quality first and integrity-based operation, always putting product quality control in the primary position of enterprise development. We have built a scientific, standardized and comprehensive enterprise management system, and have established a strict whole-process inspection and quality tracking system covering raw material procurement, production and processing, finished product testing to factory delivery. Every batch of raw materials will be sampled and inspected strictly before entering the production link. All finished steel ball products will undergo full automatic screening through professional roller bar sorting equipment and photoelectric surface defect detectors to eliminate defective products 100%. The rigorous whole-process quality control mechanism effectively ensures the high precision, high stability and high durability of our products, laying a solid foundation for long-term stable cooperation with global customers.
Our Products
Custom steel ball
Model: Custom
Parameters: Custom
Stainless Steel Ball
Model: Stainless Steel Ball
Parameters: Austenitic: Sizes 0.5 mm – 50.8 mm (0.020"–2.000"); ABMA precision G10–G1000; HRC 25–39 (annealed, soft); Ra fine; ISO 3290 / ABMA Std 10
Martensitic: Sizes 1.0 mm – 50.8 mm; G10–G100; HRC 50–55 (heat-treated); DIN 5401 / ISO 3290
Martensitic, high-carbon high-hardness stainless: Sizes 0.8 mm – 50.8 mm; G5–G100; HRC 58–65 (through-hardened); DIN 5401 / ABMA Std 10
Hastelloy Steel Ball
Model: Hastelloy nickel-based superalloy (Ni–Cr–Mo–W)
Parameters: Per specification; typical 3 mm – 50 mm; oxidation and acid resistant
M50 Steel Ball
Model: High-speed molybdenum alloy tool steel
Parameters: Per aerospace specification; typical 3 mm – 50 mm; HRC 62–66; high hot hardness
Duplex Stainless Steel Ball
Model: Duplex stainless steel
Parameters: Per specification; typical 10 mm – 100 mm; high strength and corrosion resistance
Hollow Steel Ball
Model: Custom – seamless or welded (AISI 304 / 316 / carbon steel)
Parameters: Outside diameter and wall thickness per specification; through-holes available
Electroplated Steel Ball
Model: Custom – zinc / nickel / chrome plated (base: carbon or alloy steel)
Parameters: Base 1 mm – 50.8 mm; plating thickness per specification (e.g. zinc 5–25 µm)
Drilled Steel Ball
Model: Custom – through-drilled or tapped (AISI 52100 / 304 / 440C)
Parameters: Drilled diameters and thread sizes per drawing; stock sizes 6 mm – 50.8 mm typical
Precision Steel Ball
Model: Precision Steel Ball
Parameters: 0.5 mm – 50.8 mm; Grade G3 / G5 / G10 / G16 / G25; sphericity within micro-inches
Non-Standard Steel Ball
Model: Custom – per customer drawing / specification
Parameters: Sizes, tolerances, materials and features made to order (prototypes to production)
Machined Steel Ball
Model: Custom – per drawing (AISI 52100 / 1045 / 4140 optional)
Parameters: 10 mm – 200 mm+; ISO tolerance classes; roughness and hardness per specification
Carbon Steel Ball
Model: Carbon Steel Ball
Parameters: 1 mm – 50.8 mm; Grade G100–G2000; low-carbon soft or HRC 55–60 when hardened
304 Stainless Steel Ball
Model: 304 Stainless Steel Ball
Parameters: 1 mm – 50.8 mm; Grade G100–G1000; annealed soft; mirror polish available
316 Stainless Steel Ball
Model: 316 Stainless Steel Ball
Parameters: 1 mm – 50.8 mm; Grade G100–G1000; annealed soft; excellent chloride resistance
440C Stainless Steel Ball
Model: 440C Stainless Steel Ball
Parameters: 0.5 mm – 50.8 mm; Grade G10–G1000; HRC 58–62; max 0.07% P/S
420C Stainless Steel Ball
Model: 420C Stainless Steel Ball
Parameters: 1 mm – 50.8 mm; Grade G25–G1000; HRC 50–55; corrosion resistant
Chrome Steel Ball
Model: Chrome Steel Ball
Parameters: 1 mm – 50.8 mm; Grade G10–G1000; HRC 60–66; isotropic finish available
Bearing Steel Ball
Model: Bearing Steel Ball
Parameters: 0.5 mm – 50.8 mm (1/64"–2"); Grade G10–G1000; HRC 60–66; Ra ≤ 0.05 µm
Company Gallery
Certifications & Awards
Success Stories & Case Studies
Biopharma & Specialty Chemical Equipment Maker
Met aggressive process chemistry requirements while maintaining hygienic integrity
Ultra-corrosion-resistant alloy; material certificate; clean-process compatible
Chemical & Petrochemical Plant OEM
Exceptional resistance to strong acid and localized corrosion; minimal valve trim replacement
Hastelloy C-276 / N10276; EN 10204 3.1; MTR + PMI; extreme-corrosion documentation
High-Speed Spindle & Machine-Tool OEM
Stable performance at high DN; extended spindle service interval
High-speed, high-temperature bearing grade; CMM + hardness verified
Aerospace Engine Bearing Supplier
Retained hardness & dimensional stability at elevated temperature; qualified for jet-engine use
Aerospace-grade M50; AMS 6490; high-temperature capability; full traceability
Desalination Plant EPC Contractor
Outperformed 316 in aggressive chloride service; reduced replacement frequency
Engineered for high-chloride seawater; PREn >34; EN 10204 3.1 certificate
Offshore Oil & Gas Operator
PREn >34 resistance to chloride pitting/crevice corrosion; reliable in seawater
Duplex 2205; high PREn; NACE MR0175 awareness; MTR + PMI verified
Marine & Floating Equipment OEM
Controlled wall thickness & leak test ensured long-term buoyancy
Pressure/leak tested; corrosion-resistant coating options; made-to-print
Architectural & Structural Fabricator
Lightweight yet structurally capable; enabled bold architectural geometries
Custom OD & wall thickness; welding-friendly; structural calculation support
Consumer Electronics & Appliance Maker
High-gloss, durable finish improved product aesthetics and corrosion life
Mirror-bright plating; RoHS-compliant plating options; custom color
Automotive Trim & Hardware Supplier
Uniform bright plating; passed customer salt-spray specification
Zinc/nickel/Chrome plating; salt-spray report; tight plating-thickness control
Oil & Gas Equipment Supplier
Withstood sour-service surface conditions; reliable sealing performance
Made-to-print; NACE-aware material options; pressure-test support
Specialty Valve & Hydraulic OEM
CNC-drilled hole position accuracy eliminated rework at customer assembly
CNC-drilled to drawing; hole position CMM-checked; custom threads
Optical & Metrology Instrument Maker
Exceptional sphericity & surface finish; directly usable as measurement reference
Ultra-high precision; mirror polishing available; calibration certificate option
Semiconductor Equipment OEM
Sub-micron roundness helped customer meet equipment accuracy targets
G3-G10 precision range; CMM & roundness metrology; class-1000 clean-pack optional
Aerospace MRO Provider
Reverse-engineered obsolete size; kept legacy aircraft platforms serviceable
Custom size + material matching; small-batch ODM; full traceability
Specialty Bearing & Instrument Maker
Filled a size gap no catalog supplier could; enabled customer to finish a niche product line
Made-to-order non-standard sizes; low-volume friendly; MTR supplied
Robotics & Automation Integrator
Drawing-based custom geometry; consistent roundness improved motion repeatability
Full ODM service; made-to-print; fast prototyping & small-batch support
Heavy Machinery OEM
Tight tolerance enabled direct assembly without secondary grinding
CNC-machined to drawing; custom diameters & materials; CMM inspection
Furniture & Hardware Manufacturer
Cost-competitive without sacrificing functional durability
Economical choice; zinc/plated options available; PPAP-style QC docs
General Industrial Distributor
Reliable, economical supply; helped distributor consolidate multiple SKUs from one source
Factory-direct; flexible packaging; fast stock shipment; low MOQ
Commercial Kitchen Equipment OEM
Good corrosion & cleanability in humid, high-salt Gulf environment
Hygienic, easy-to-clean surface; material certificate available
Household & Sanitaryware Brand
Cost-effective corrosion-resistant solution with broad market acceptance
Most widely used stainless; RoHS; attractive bright finish; low MOQ
Pharmaceutical & Food Equipment Maker
Met hygienic-design requirements; smooth finish facilitated cleaning validation
316L available for welding; 3A/EHEDG-aligned finish; MTR + EN 10204 3.1
Marine & Offshore Equipment OEM
Excellent seawater corrosion resistance; zero chloride-stress complaints
Marine-grade 316; low carbon option (316L) available; salt-spray test report
Aerospace Bearing Supplier
Met stringent corrosion + hardness specs; supported customer AS9100 qualification
AMS-aware process controls; 100% vision + hardness inspection; full traceability
Medical Device Manufacturer
Withstood repeated autoclave cycles; high hardness and mirror-like finish extended instrument life
Premium martensitic stainless; AISI 440C with MTR; FDA-device-compatible documentation
Marine Hardware OEM
Adequate corrosion performance at competitive cost; smooth surface finish
Cost-effective stainless option; salt-spray tested; RoHS-compliant
Valve & Pump Manufacturer
Good balance of hardness and corrosion resistance; lower total cost vs 440C for moderate-duty service
Martensitic stainless; hardenable to HRC 50-55; MTR + material certificate
Power-Tool OEM
Improved tool life under high-speed duty; zero field failures attributed to balls
High-hardness HRC 60-66; automated 100% visual sorting; fast 15-day shipment
Automotive Component Supplier
Stable quality across shipments; customer reduced incoming inspection workload
Factory-direct OEM; bilingual (EN/ES) commercial & technical support; NAFTA/USMCA-friendly supply chain
Industrial Bearing OEM
Met tight roundness/roughness specs; helped customer qualify for a premium automotive Tier-2 program
DIN/ISO-compliant material; MTR + COA supplied; PPAP-style documentation support
Tier-1 Bearing Manufacturer
Reduced bearing noise & vibration; stable, on-time delivery enabled customer to shorten lead time and lower safety stock
ABMA G10 precision; 100% automated vision inspection; consistent HRC 60-66; direct-from-mill traceability
Company & Product Videos
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