Certainly! Here’s a list of some of the most well-known leading global suppliers of carbon steel seamless casings:

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Leading Global Suppliers of Carbon Steel Seamless Casings

1. Tenaris

   • A leading global manufacturer and supplier of steel pipes, Tenaris offers a wide range of seamless casings for the energy sector.

2. OCTG (Oil Country Tubular Goods)

   • A variety of manufacturers produce OCTG products, including seamless casings, but notable companies include:
     • U. S. Steel
     • Nucor Corporation
     • Valiant Steel

3. TMK Group

   • One of the largest manufacturers of pipes for the oil and gas industry, TMK supplies seamless casings and other tubular products.

4. JFE Steel Corporation

   • A major player in specialty and high-strength steel products, supplying seamless carbon steel casings for various applications.

5. Nippon Steel Corporation

   • Offers a variety of seamless steel products, including casings, with a strong global presence.

6. Böhler Edelstahl GmbH & Co KG

   • A company known for high-quality special steel products including seamless casings, primarily for high-performance applications.

7. Maruichi Steel Tube Ltd.

   • Recognized for its production of seamless steel pipes and tubes for various industries, including oil and gas.

8. Vallourec

   • A global leader in premium tubular solutions, providing seamless casings and other products tailored to energy and industrial sectors.

9. Severstal

   • A Russian steel company that produces a wide range of steel products, including seamless tubing for the oil and gas industry.

10. Luvata

    • Specializes in high-performance seamless casings and has a significant market presence in the energy sector. ```

This list includes companies that are recognized for their production and supply of carbon steel seamless casings, particularly for the oil and gas industry. Keep in mind that the market dynamics can evolve, and emerging companies may also play a role.