Rolling mill equipped with on-line roll grinding system and grinding wheel

A rolling mill equipped with an on-line roll grinding system comprising:

• a disk type grinding wheel positioned to face and grind a mill roll during rolling operations of the rolling mill, and
• a grinding wheel drive unit rotatably driving said grinding wheel independently of rotational driving of said mill roll,
• wherein said grinding wheel comprises a wheel disk and an abrasive layer formed on one side of said wheel disk, said wheel disk being configured to have a spring constant so as to be sufficiently elastic to allow a portion of the wheel disk contacting the mill roll being ground to locally elastically bend while being pressed against the mill roll and to absorb vibration from said mill roll being ground during grinding of said mill roll,
• wherein said on-line roll grinding system further comprises control means for measuring an inclination of the axis of said mill roll and controlling said grinding wheel movement toward said axis and parallel to said axis so that said grinding wheel moves following a target roll profile in consideration of the inclination of the axis of said mill roll.

A rolling mill equipped with an on-line roll grinding system comprising:

• a disk type grinding wheel positioned to face and grind a mill roll during rolling operations of the rolling mill, and
• a grinding wheel drive unit rotatably driving said grinding wheel independently of rotational driving of said mill roll,
• wherein said grinding wheel comprises a wheel disk and an abrasive layer formed on one side of said wheel disk, said wheel disk being configured to have a spring constant so as to be sufficiently elastic to allow a portion of the wheel disk contacting the mill roll being ground to locally elastically bend while being pressed against the mill roll and to absorb vibration from said mill roll being ground during grinding of said mill roll, and
• wherein said grinding wheel, said grinding wheel drive means, said grinding wheel movement means and said grinding wheel traverse means constitute one grinding head unit, and said on-line roll grinding system further comprises a reference small-diameter zone formed on at least one end of said mill roll and having a known diameter smaller than the diameter of a roll barrel, and a displacement meter provided on said grinding head unit for measuring a distance from said grinding head unit to said mill roll.

A rolling mill equipped with an on-line roll grinding system comprising:

• a disk type grinding wheel positioned to face and grind a mill roll during rolling operations of the rolling mill,
• a grinding wheel drive unit rotatably driving said grinding wheel independently of rotational driving of said mill roll,
• wherein said grinding wheel comprises a wheel disk spindle and an abrasive layer formed on one side of said wheel disk, said wheel disk being configured to have a spring constant so as to be sufficiently elastic to allow a portion of the wheel disk contacting the mill roll being ground to locally elastically bend while being pressed against the mill roll and to absorb vibration from said mill roll being ground during grinding of said mill roll,
• further comprising first displacement detector means for measuring a stroke of said grinding wheel movement means, second displacement detector means for measuring a stroke of said grinding wheel in the roll axial direction given by said grinding wheel traverse means, load detecting means for measuring the contact force between said grinding wheel and said mill roll, and an on-line profile meter including second profile calculating means for calculating a profile of said mill roll from both the stroke measured by said first displacement detector means and the stroke measured by said second displacement detector means under a condition of keeping the contact force measured by said load detecting means constant.

A rolling mill equipped with an on-line roll grinding system comprising:

• a disk type grinding wheel positioned to face and grind a mill roll during rolling operations of the rolling mill, and
• a grinding wheel drive unit rotatably driving said grinding wheel independently of rotational driving of said mill roll,
• wherein said grinding wheel comprises a wheel disk attached to a spindle and an abrasive layer formed on one side of said wheel disk, said wheel disk being configured to have a spring constant so as to be sufficiently elastic to allow a portion of the wheel disk contacting the mill roll being ground to locally elastically bend while being pressed against the mill roll and to absorb vibration from said mill roll being ground during grinding of said mill roll, and
• wherein said wheel has a spring constant of 1000 Kgf/mm to 30 Kgf/mm.

A rolling mill equipped with an on-line roll grinding system comprising:

• a disk type grinding wheel positioned to face and grind a mill roll during rolling operations of the rolling mill, and
• a grinding wheel drive unit rotatably driving said grinding wheel independently of rotational driving of said mill roll,
• wherein said grinding wheel comprises a wheel disk and an abrasive layer formed on one side of said wheel disk, said wheel disk being configured to have a spring constant so as to be sufficiently elastic to allow a portion of the wheel disk contacting the mill roll being ground to locally elastically bend while being pressed against the mill roll and to absorb vibration from said mill roll being ground during grinding of said mill roll, and
• further comprising load detecting means for measuring the contact force between said grinding wheel and said mill roll, and a controller controlling a drive of said grinding wheel movement to optionally change the contact force measured by said load detecting means so that a grinding rate of said grinding wheel on said mill roll is changed, for thereby grinding said mill roll into a predetermined roll profile.

A rolling mill equipped with an on-line roll grinding system comprising:

• a disk type grinding wheel positioned to face and grind a mill roll during rolling operations of the rolling mill, and
• a grinding wheel drive unit rotatably driving said grinding wheel independently of rotational driving of said mill roll,
• wherein said grinding wheel comprises a wheel disk and an abrasive layer formed on one side of said wheel disk, said wheel disk being configured to have a spring constant so as to be sufficiently elastic to allow a portion of the wheel disk contacting the mill roll being ground to locally elastically bend while being pressed against the mill roll and to absorb vibration from said mill roll being ground during grinding of said mill roll, and
• further comprising load detecting means for measuring the contact force between said grinding wheel and said mill roll, and a controller controlling said grinding wheel movement so that the contact force measured by said load detecting means is held constant, and for simultaneously controlling said grinding wheel traverse movement to optionally change a traverse speed of said grinding wheel in the roll axial direction so that a grinding rate of said grinding wheel on said mill roll is changed, for thereby grinding said mill roll into a predetermined roll profile.

A rolling mill equipped with an on-line roll grinding system comprising:

• a disk type grinding wheel positioned to face and grind a mill roll during rolling operations of the rolling mill, and
• a grinding wheel drive unit rotatably driving said grinding wheel independently of rotational driving of said mill roll,
• wherein said grinding wheel comprises a wheel disk and an abrasive layer formed on one side of said wheel disk, said wheel disk being configured to have a spring constant so as to be sufficiently elastic to allow a portion of the wheel disk contacting the mill roll being ground to locally elastically bend while being pressed against the mill roll and to absorb vibration from said mill roll being ground during grinding of said mill roll,
• further comprising a grinding wheel movement means which includes a rotation drive source, and a ball screw mechanism or a gear mechanism having a small backlash and converting rotation of said rotation drive source into axial movement of said grinding wheel movement means for moving said grinding wheel back and forth relative to said mill roll.

A rolling mill equipped with an on-line roll grinding system comprising:

• a disk type grinding wheel positioned to face and grind a mill roll during rolling operations of the rolling mill, and
• a grinding wheel drive unit rotatably driving said grinding wheel independently of rotational driving of said mill roll,
• wherein said grinding wheel comprises a wheel disk and an abrasive layer formed on one side of said wheel disk, said wheel disk being configured to have a spring constant so as to be sufficiently elastic to allow a portion of the wheel disk contacting the mill roll being ground to locally elastically bend while being pressed against the mill roll and to absorb vibration from said mill roll being ground during grinding of said mill roll,
• wherein said on-line roll grinding system comprises at least two grinding head units for each of said mill rolls, each of said two grinding head units including one of said grinding wheels, a grinding wheel drive means, grinding wheel movement means, and grinding wheel traverse means, whereby said two grinding head units can grind said mill roll independently of each other.

A rolling mill equipped with an on-line roll grinding system comprising:

• a disk type grinding wheel positioned to face and grind a mill roll during rolling operations of the rolling mill, and
• a grinding wheel drive unit rotatably driving said grinding wheel independently of rotational driving of said mill roll,
• wherein said grinding wheel comprises a wheel disk and an abrasive layer formed on one side of said wheel disk, said wheel disk being configured to have a spring constant so as to be sufficiently elastic to allow a portion of the wheel disk contacting the mill roll being ground to locally elastically bend while being pressed against the mill roll and to absorb vibration from said mill roll being ground during grinding of said mill roll,
• and further comprising displacement detector means for measuring a stroke of said grinding wheel in the roll axial direction given by a grinding wheel traverse means, load detecting means for measuring the contact force between said grinding wheel and said mill roll, an on-line profile meter including first profile calculating means for calculating a profile of said mill roll from both the contact force measured by said load detecting means and the stroke measured by said displacement detector means under a condition of keeping a stroke of said grinding wheel movement means constant.

A rolling method by use of a rolling mill equipped with an on-line roll grinding system comprising a grinding unit for grinding a mill roll, and traverse means for moving said grinding unit in an axial direction of said mill roll, wherein the method comprises the steps of:

• providing said grinding unit with a support member of a wheel disk type having an abrasive layer formed on a surface thereof and configured to provide an elastically deforming function to allow a portion of the support member contacting the mill roll to locally bend upon being pressed against the mill roll;
• grinding an outer periphery of said mill roll being rotated under vibration into a desired roll profile by rotatably driving said support member of the wheel disk type, pressing said support member being rotated against said mill roll, and traversing said support member being pressed against said mill roll in the axial direction of said mill roll;
• and
• rolling a strip by said mill roll being ground.