センタレス研磨 ステンレス磨棒鋼 機械加工のことなら精研工業株式会社 Centerless Grinding & Polishing, Stainless Steel Cold Drawn Steel Bars and Machining Seiken Kogyo Co., Ltd.


Features of Centerless Grinding & Polishing


Centerless grinding & polishing is a method of grinding the outer periphery of a workpiece by adjusting the rotation and feed of the workpiece while supporting it between a fixed support blade and a rotating adjusting wheel and grinding wheel. There is no need to attach the workpiece to the grinding machine, and it is possible to handle from small lots to mass production. The polishing accuracy can be kept uniform because there is no deflection due to the weight of the workpiece during the process.

センタレス研磨の機材の研磨工程 センタレス研磨の仕組み

他の研磨方法との比較 Comparison with Other Grinded Steel Barss


Centerless grinding & polishing is a processing method that can respond to various demands such as cost, delivery time, and dimensional accuracy compared to cylindrical polishing and drawing. It is also suitable for small lots and large variety manufacturing, and is characterized by its little distortion in long length, and it does not denature such as becoming magnetic during processing.



Advantages of Centerless Grinding & Polishing Over Cylindrical Polishing


Benefits of Centerless Grinding & Polishing


Reduction of Delivery Time and Cost Although Accuracy is Slightly Reduced


Reduction of the Cylindrical Polishing Process


Long Length Machining and High Accuracy


Advantages of Centerless Grinding & Polishing Over Cylindrical Polishing

  • ■ ワークのしなりの影響を受けないため、より長尺物の加工が可能。
  • ■ 連続加工性が高いため、加工時間が短くなる。
  • ■ 一回あたりの切削量が多いため、作業効率が高い。
  • ■ コストが抑えられる。
  • ■ Longer workpieces can be processed because
    they are not affected by the bending of workpieces.
  • ■ High continuous workability reduces processing time.
  • ■ High work efficiency due to large amount of cut per operation.
  • ■ Cost reduction.

円筒研磨とセンタレス研磨の併用のメリット Advantages of Combined Usage of Cylindrical Polishing and Centerless Grinding & Polishing


Processing close to the same level as cylindrical polishing is possible with short delivery time and low cost.
We aim to shorten the delivery time and reduce costs by reducing the number of Cylindrical polishing steps in the secondary processing of
parts and by saving labor.



Centerless grinding & polishing is inferior in accuracy to cylindrical polishing. However, centerless grinding & polishing enables to perform long length processing and shorten the processing time, of which is hard to achieve by the cylindrical polishing. If ultra-high precision is not required, we believe that the advantages of centerless grinding & polishing can be maximized. In addition, by combining the benefits of cylindrical polishing and centerless grinding & polishing, it is possible to improve the accuracy while leveraging the advantage of centerless grinding & polishing.
Please do not hesitate to contact us when you require precise parts while the cost and the delivery schedule are tight.


Advantages of Centerless Grinding & Polishing Over Drawing Process


Benefits of Centerless Grinding & Polishing


Processed Product with A Higher Accuracy


Material is Not Magnetized or Denatured


Advantages of Centerless Grinding & Polishing Over Drawing Process

  • ■ 表面肌がきれい。
  • ■ より高精度な長尺加工が可能。
  • ■ 比較的、多品種・小ロットに対応がしやすい。
  • ■ ダイス径にとらわれることなく、製品の径を自在に変更できる。
  • ■ 加工時に、磁性を帯びたり変性をおこさない。
  • ■ Beautiful surface skin.
  • ■ Higher precision and longer length processing is possible.
  • ■ Relatively easy to handle many kinds and small lots manufacturing.
  • ■ The diameter of the product can be changed freely,
    regardless of the die diameter.
  • ■ Does not become magnetized or denatured during processing.


Stainless steel round bars are mainly used in automobiles, boats and ships, aircraft, various precision parts, industrial machines, home appliances, and civil engineering. More recently, as home appliances and electrical appliances have become more sophisticated and larger in size, stainless steel round bars, which have both durability and precision, are now used in manufacturing lines.
In addition, polished round bars manufactured by drawing processing generally have h9 tolerances, but if they are processed by centerless grinding & polishing, it can correspond to all dimensional tolerances such as h7, h6, as well as f8, g6, etc. Centerless grinding & polishing removes the surface of the material, that the removal of decarburized layers can be expected.
Please feel free to contact us if you need to improve durability and accuracy or trying to respond to the diversifying customer needs.




Our polished round bars have a wide range of outer diameters from φ5mm to φ70mm and lengths from 200mm to 6,000mm. In addition to the usually required accuracy of 3/100mm to 4/100mm, we have also achieved much higher accuracy of 5 / 1,000mm. We also support a wide range of materials such as iron, SUS, aluminum and brass.

BARSのサイズ範囲 PIPESのサイズ範囲




We perform centerless grinding & polishing of a wide range of steel types.
Please feel free to contact us for steel types other than those listed below.

Stainless Steel
オーステナイト系(SUS304等)Austenite (SUS304, etc.)
フェライト系(SUS403、430等)Ferrite (SUS403, 430, etc.)
マルテン(SUS410等)Martens (SUS410, etc.)
高強度ステンレス鋼(SUS630等)High Strength Stainless Steel (SUS630, etc.)
一般的な特殊鋼(SS材、S-C材等General Special Steel (SS Material, S-C Material, etc.)
純チタン(JIS1種、2種等)Pure Titanium (JIS Class 1, Class 2)
マルテン(SUS410等)Martens (SUS410, etc.)
伸銅Wrought Copper
アルミ(AL6000系、7000系)などAluminum (AL6000 Series, 7000 Series, etc.)