Cold pilger rolling mill and method for forming a hollow shell into a tube
AssigneeSandvik Materials Technology Deutschland GmbH
InventorThomas Frobose
Life of this patent
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Abstract
A cold pilger rolling mill includes a pair of rolls rotatably attached to a roll stand, a crank drive on a driveshaft, which is rotatably mounted around a rotation axis, with a counterweight attached to the crank drive at a radial distance from the rotation axis, and a push rod with a first and a second end. The first end of the push rod is rotatably attached on the crank drive wherein, during the operation of the mill, a rotation of the crank drive is converted into a translation movement of the roll stand between a first and a second reversal position. The radial distance of the first end of the push rod from the rotation axis is adjustable, so that the distance between the two reversal positions of the translation movement of the roll stand is adjustable.
Claims14
A cold pilger rolling mill for forming a hollow shell into a tube, the cold pilger rolling mill comprising:
- a pair of rolls rotatably attached to a roll stand;
- a rolling mandrel tool;
- a feeding clamping carriage for receiving the hollow shell, wherein during the operation of the mill, the feeding clamping carriage moves between a first and a second extreme position in such a manner that the hollow shell moves stepwise in a direction toward the tool;
- a crank drive disposed on a driveshaft and rotatably mounted around a rotation axis;
- a counterweight attached to the crank drive at a radial distance from the rotation axis;
- and
- a push rod having a first and a second end, the first end of the push rod being rotatably attached on the crank drive around a crank pin at a radial distance from the rotation axis, and wherein the second end of the push rod is attached to the roll stand, so that, during the operation of the mill, a rotation of the crank drive is converted into a translation movement of the roll stand between a first reversal point and a second reversal position, the radial distance of the first end of the push rod from the rotation axis being adjustable, so that a distance between the two reversal positions of the translation movement of the roll stand is adjustable, wherein the crank drive includes a through hole having a cross-section which is at least in some sections radially symmetric, but not rotationally symmetric, for receiving the crank pin, a base body with a front side and a back side, a pin section arranged on the front side and a securing section arranged on the back side, wherein the base body has a cross section, which at least in some sections is complementary to the cross-section of the through hole, so that the base body is received in a twist-proof manner and with positive lock in the through hole.
A method for forming a hollow shell into a tube, comprising the steps of:
- providing a cold pilger rolling mill having a pair of rolls rotatably attached to a roll stand, a rolling mandrel tool, and a feeding clamping carriage with the hollow shell received therein;
- moving the feeding clamping carriage between a first extreme position and a second extreme position, such that the hollow shell moves stepwise in a direction toward the tool;
- forming the hollow shell into the tube using the tool, wherein a rotation of a crank drive is converted into a translation movement of the roll stand between a first reversal position and a second reversal position, wherein the crank drive is rotatably mounted around a rotation axis on a driveshaft, a counterweight is attached at a radial distance from the rotation axis on the crank drive, and a push rod is arranged with a first and a second end so that the first end of the push rod is rotatably attached at a radial distance from the rotation axis around a crank pin on the crank drive and the second end of the push rod is attached to the roll stand;
- and
- adjusting the distance between the two reversal positions of the translation movement of the roll stand by adjusting the radial distance of the first end of the push rod from the rotation axis, wherein the crank drive has a through hole with a cross section that is at least in some sections radially symmetric but not rotationally symmetric for receiving the crank pin, the crank pin having a base body with a front side and a back side, a pin section being arranged on the front side and a securing section being arranged on the back side, wherein the base body has a cross section at least in some sections to be complementary to the cross section of the through hole, so that the base body can be received in a twist-proof manner and with positive lock in the through hole.
Dependencies are inferred from the claim text.