TECHNOLOGY

SPECIAL WELDING AND INDUCTION HARDENING

TECHNOLOGY

SPECIAL WELDING AND INDUCTION HARDENING

Special Welding and Induction Hardening for Large-diameter Hollow Roll

This long-term collaboration relationship between DHF and KMT which is based on the deep trust leaded DHF’s investment toward KMT’s share. Now DHF holds a 5% of shareholding in KMT

Mr.Lee,Kee-Jung, a establisher of KMT, had tried to learn Japanese advanced heat treatment technology since he established KMT in 1984. At that time he met Mr.Matsubara who visited Korea to teach a heat treatment technology to several Korean small-medium sized companies.
A chance meeting had developed to a strong relationship with a friendship and trust after a few years.
In IMF financial crisis, Mr.Lee,Kee-Jung had a lot of trouble as other most Korean companies. At that time, Mr.Matsubara suggested that KMT make a DHP Roll(a large-diameter hollow Roll developed by DHF) in Korea.
The technology for DHP Roll can be classified to a special welding technology to get no hardness difference between plate and welded bead surface area of the Roll after induction hardening and an induction hardening technology to get uniform surface hardness distribution.
Because this technology for DHP Roll ensures same surface hardness in all area of the Roll after induction hardening, a large-diameter hollow Rolls was able to be manufactured by a method of plate-bending, not Forged Ring.
DHP Roll satisfies both price and quality as the Forged Ring type Roll is very expensive & wasteful and the Centrifugal Casting type Roll has many defects on its surface.
It is why most Japan and Korean steel manufacturing companies(Nippon Steel, JFE, KOBE Steel, POSCO, Hyundai Steel etc.) adopt this DHP Roll in their production line for high grade steel sheet.
Based on DHF’s technological guidance and assistance, KMT has become No.1 company in a Korean large-diameter hollow Roll’s industry.
This long-term collaboration relationship between DHF and KMT which is based on the deep trust leaded DHF’s investment toward KMT’s share. Now DHF holds a 5% of shareholding in KMT

Mr.Lee,Kee-Jung, a establisher of KMT, had tried to learn Japanese advanced heat treatment technology since he established KMT in 1984. At that time he met Mr.Matsubara who visited Korea to teach a heat treatment technology to several Korean small-medium sized companies.
A chance meeting had developed to a strong relationship with a friendship and trust after a few years.
In IMF financial crisis, Mr.Lee,Kee-Jung had a lot of trouble as other most Korean companies. At that time, Mr.Matsubara suggested that KMT make a DHP Roll(a large-diameter hollow Roll developed by DHF) in Korea.
The technology for DHP Roll can be classified to a special welding technology to get no hardness difference between plate and welded bead surface area of the Roll after induction hardening and an induction hardening technology to get uniform surface hardness distribution.
Because this technology for DHP Roll ensures same surface hardness in all area of the Roll after induction hardening, a large-diameter hollow Rolls was able to be manufactured by a method of plate-bending, not Forged Ring.
DHP Roll satisfies both price and quality as the Forged Ring type Roll is very expensive & wasteful and the Centrifugal Casting type Roll has many defects on its surface.
It is why most Japan and Korean steel manufacturing companies(Nippon Steel, JFE, KOBE Steel, POSCO, Hyundai Steel etc.) adopt this DHP Roll in their production line for high grade steel sheet.
Based on DHF’s technological guidance and assistance, KMT has become No.1 company in a Korean large-diameter hollow Roll’s industry.
This long-term collaboration relationship between DHF and KMT which is based on the deep trust leaded DHF’s investment toward KMT’s share. Now DHF holds a 5% of shareholding in KMT