The world No. 1 in crude steel production steel plant, over 70% of the HSS for bar and wire are from us.

LMM GROUP main products focus on the cold and hot plate & wide strip mill rolls and heavy section mill rolls and big casting & forging pieces.

LMM GROUP Certification


Quality Defects of Cold Rolled Products and Corrective Measures(2)


Plate shape defects

1. Beveling, pickling rolling, finishing, etc. Refers to the beveling of steel coils or strips when trimming the edges

2. Sickle bending Cold rolling, smoothing and smoothing The rolling force on both sides of the strip is unbalanced, the response time of the rolling force is lagging, or the roll gap is uneven (the roll gap is not well adjusted) or the raw material density and hardness are uneven.

3. Wave shape (subdivided into unilateral wave, double wave, medium wave, oblique wave, etc.) Cold rolling, smoothing and smoothing raw material density and hardness are not uniform, rolling force during rolling and roll bending force adjustment response is not fast or not It is caused by excessive fluctuations in the tension of the steel and strip steel. In addition, the large difference in the diameter of the upper and lower rolls will also cause waves.

4. Buckling Hot rolling, cold rolling, smoothing and leveling Uneven density or hardness in the thickness direction of the raw material, resulting in uneven plasticity on the upper and lower sides of the steel plate

Roll-type defects

1. Tower type crimping process

2. Bulge crimping process The edge of the steel belt is ultra-thin and forms a steel coil bulging during the continuous crimping process

3. Drum lugs crimping process For galvanized coils, if the edges are too thick, the two ends of the coil may bulge during coiling

Size defects

1. Thickness tolerance, rolling process, inaccurate rolling control, etc.

2. Width short ruler Trimming process Causes of inaccurate trimming or defects in raw material edges

3. The length is out of tolerance, the steel plate slitting process, the reason for the control accuracy, etc.

Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.

A: Payment<=1000USD, 100% in advance. Payment>=1000USD, 30% T/T in advance ,balance before shippment.

Always a pre-production sample before mass production;
Always final Inspection before shipment;
During the epidemic, provide remote detection technical support

Tell us a little about your application and we’ll get back to you to finalize a quotation to meet your needs as quickly as possible.

Rolling mill rolls product

Classification by roll material:

Cast iron mill rolls

  • Alloy indefinite chilled cast iron rolls
  • Alloy chilled cast iron rolls
  • Alloy SG ductile cast iron roll
  • Pearlitic ductile cast iron roll
  • Bainite ductile cast iron roll
  • Centrifugal cast iron roll

Cast steel mill rolls   

  • Alloy cast steel rolls
  • Semi-steel roller
  • Graphite steel rolls
  • High-chromium steel roll
  • High-speed steel roll

Forging mill rolls

Sort by position on the rolling mill:

Work rolls
backup rolls

Intermediate roll

Product advantage

The world No. 1 in crude steel production steel plant, over 70% of the HSS for bar and wire are from us.

LMM high-speed steel rolls have higher steel passing per groove (times) due to their good wear resistance, which saves roll changing time, improves rolling mill operation rate, reduces roll consumption, and improve the overall efficiency of the factory.
Generally, the amount of steel passing in a single groove (times) is 3 to 5 times that of cast iron rolls.

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We would be happy to help and advise if you have any questions or inquiries.