Gray iron castings for strength and value

Milson delivers high-quality gray iron castings to U.S. manufacturers who demand performance, reliability, and value. Gray iron offers excellent compressive strength and machinability at a lower cost, making it ideal for components where compressive strength, rigidity, and machinability matter most.

    Why gray iron for castings

    Gray iron is a proven solution for applications where strength, thermal control, and vibration damping matter, without adding cost or complexity. It’s ideal for production-scale runs where repeatability and ease of machining are priorities.

    Icons Cost Saving

    Cost-effective for large production runs

    Icons Fist Strength Tough

    Strong compressive strength for structural reliability

    Icons Ruler Measure Accuracy

    Good machinability for tight tolerances

    Icons Flash Impact

    Excellent vibration damping for noise and shock control

      Milson Product Heavy Duty Cast Plates Cast Iron

      Where gray iron is used

      Gray iron is widely used in heavy-duty applications that demand durability and stability. Milson supplies gray iron castings for a broad range of industrial components.

      • Agricultural equipment parts
      • Pump bodies and impellers
      • Machine tool frames
      Typical properties (values vary by grade and specification):
      • Compressive strength: 100–200 ksi
      • Tensile strength: 20–60 ksi
      • Hardness: 150–250 BHN
      • Thermal conductivity: High — effective for heat dissipation
      • Machinability: Excellent
      • Vibration damping: Superior for noise and shock control

      We cast gray iron components to meet defined strength and hardness targets across a variety of ASTM grades.

      ASTM A48 (Gray Iron) mechanical properties

      GradeTensile Strength, min
      (KSI)
      Class 2020
      Class 2525
      Class 3030
      Class 3535
      Class 4040
      Class 4545
      Class 5050
      Class 5555
      Class 6060

        Full-service gray iron casting, start to finish

        Every project is backed by Milson’s full foundry and machining capabilities. These services support design, production, and quality from start to finish.

        Casting design and engineering

        Casting design and engineering for accuracy and repeatability

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        Sand and shell mold casting

        Flexible processes for small to large parts with reliable results.

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        Short-run prototyping

        Validate form, fit, and function before scaling to production.

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        Machining

        Fully finished, assembly-ready parts with tight tolerances.

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        Quality assurance

        Traceability and documentation to meet demanding specifications.

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        Let’s solve your casting challenges

        If you’re designing a gray iron component or improving an existing part, our engineers provide clear guidance, fast feedback, and practical solutions.

        Milson Team 03