A wire rod rolling roller is disclosed. In one aspect, the wire rod rolling roller includes upper and lower rollers spaced apart from each other and configured to roll a wire rod passing therebetween and upper and lower drive shafts fixedly extending through the centers of the upper and lower rollers, respectively, and configured to rotate the upper and lower rollers. The wire rod rolling roller also includes upper and lower bearing housings respectively disposed on one side of the upper drive shaft and one side of the lower drive shaft, and configured to support the upper and lower drive shafts. The wire rod rolling roller further includes a journal bearing inserted into the upper and lower bearing housings and in surface contact with the upper and lower drive shafts to minimize fiction and a gap adjustment device configured to adjust a gap between the upper and lower rollers.

A wire rod rolling roller is disclosed. In one aspect, the wire rod rolling roller includes upper and lower rollers spaced apart from each other and configured to roll a wire rod passing therebetween and upper and lower drive shafts fixedly extending through the centers of the upper and lower rollers, respectively, and configured to rotate the upper and lower rollers. The wire rod rolling roller also includes upper and lower bearing housings respectively disposed on one side of the upper drive shaft and one side of the lower drive shaft, and configured to support the upper and lower drive shafts. The wire rod rolling roller further includes a journal bearing inserted into the upper and lower bearing housings and in surface contact with the upper and lower drive shafts to minimize fiction and a gap adjustment device configured to adjust a gap between the upper and lower rollers.

Embodiments of the present invention provide a hollow cylindrical filter for removing efficiently foreign substances from fluids. This is performed by forming complicated passages including an axial direction and a radial direction in the filter. The hollow cylindrical filter is formed by winding a metal wire rod in a spiral and multilayered manner. The metal wire rod includes a recess formed throughout the entire length in a longitudinal direction, or recesses repeated along said longitudinal direction. Some wire rod layers extend in an axial direction of the hollow cylindrical filter while the adjacent wire rod layers extend in an intersecting direction, thereby forming a plurality of communication paths for communicating between the overlapping wire rod layers. Additionally, a space is formed between the recess of one wire rod layer and another adjacent wire rod layer, allowing the plurality of communication paths to communicate with each other.

Embodiments of the present invention provide a hollow cylindrical filter for removing efficiently foreign substances from fluids. This is performed by forming complicated passages including an axial direction and a radial direction in the filter. The hollow cylindrical filter is formed by winding a metal wire rod in a spiral and multilayered manner. The metal wire rod includes a recess formed throughout the entire length in a longitudinal direction, or recesses repeated along said longitudinal direction. Some wire rod layers extend in an axial direction of the hollow cylindrical filter while the adjacent wire rod layers extend in an intersecting direction, thereby forming a plurality of communication paths for communicating between the overlapping wire rod layers. Additionally, a space is formed between the recess of one wire rod layer and another adjacent wire rod layer, allowing the plurality of communication paths to communicate with each other.

In a rolled steel bar or rolled wire rod for a cold-forged component having a predetermined chemical composition, Y1 represented by Y1=[Mn]×[Cr] and Y2 represented by Y2=0.134×(D/25.4−(0.50×√[C])/(0.50×√[C]) satisfy Y1>Y2, the tensile strength is 750 MPa or less, an internal structure is a ferrite-pearlite structure, and the ferrite fraction in the internal structure is 40% or greater.

In a multi-roll table ring-rolling mill and method, a mandrel roll can be switched from a rolling state into a free-running state, when a predetermined ring diameter is reached, even if the roll gap minimum has not yet been reached, in order to improve the size accuracy of the rolled rings. A mandrel roll table rotating about a mandrel table axle is used, along with at least one main roll rotating about a main roll axle and first and second mandrel rolls that are mounted in the mandrel roll table, and a relief device to relieve at least the first mandrel roll of rolling forces. The main roll axle and the mandrel roll table axle are mounted in unchangeable manner and eccentric to one another, at least during the rolling process. The relief device acts independent of the main roll axle and the mandrel roll table axle are eccentric to one another.

In a multi-roll table ring-rolling mill and method, a mandrel roll can be switched from a rolling state into a free-running state, when a predetermined ring diameter is reached, even if the roll gap minimum has not yet been reached, in order to improve the size accuracy of the rolled rings. A mandrel roll table rotating about a mandrel table axle is used, along with at least one main roll rotating about a main roll axle and first and second mandrel rolls that are mounted in the mandrel roll table, and a relief device to relieve at least the first mandrel roll of rolling forces. The main roll axle and the mandrel roll table axle are mounted in unchangeable manner and eccentric to one another, at least during the rolling process. The relief device acts independent of the main roll axle and the mandrel roll table axle are eccentric to one another.

A billet (2) is rolled to a rod (3) in a rolling mill. The rod (3) exits the rolling mill with a finishing temperature (TE1). A rear laser measurement device (8) arranged downstream of the rolling mill detects the head end and the speed (v) of the rod (3). The detected speed (v) of the rod (3) is integrated to its length and an instantaneous length (L) of the rod (3) is determined. Dependent on the determined instantaneous length (L) of the rod (3), cutting commands (S) to a rear shears (5) arranged downstream of the rolling mill are provided for cutting the rod (3) in sections (6) of predetermined length (L0). The sections (6) of the rod (3) are cooled down in a cooling bed (7).

A billet (2) is rolled to a rod (3) in a rolling mill. The rod (3) exits the rolling mill with a finishing temperature (TE1). A rear laser measurement device (8) arranged downstream of the rolling mill detects the head end and the speed (v) of the rod (3). The detected speed (v) of the rod (3) is integrated to its length and an instantaneous length (L) of the rod (3) is determined. Dependent on the determined instantaneous length (L) of the rod (3), cutting commands (S) to a rear shears (5) arranged downstream of the rolling mill are provided for cutting the rod (3) in sections (6) of predetermined length (L0). The sections (6) of the rod (3) are cooled down in a cooling bed (7).

A steel wire rod includes, in terms of mass %, 0.95-1.10% C, 0.10-0.70% Si, 0.20-1.20% Mn, 0.90-1.60% Cr, 0-0.25% Mo, 0-25 ppm B, 0-0.020% P, 0-0.020% S, 0-0.0010% O, 0-0.030% N, and 0.010-0.100% Al. In a surface area of the steel wire rod, the Vickers hardness is HV 300 to HV 420, the area ratio of pearlite is 80% or more, and the area ratio of pro-eutectoid cementite is 2.0% or less. In an inner area of the steel wire rod, the area ratio of pearlite is 90% or more, and the area ratio of pro-eutectoid cementite is 5.0% or less. In the steel wire rod, the area ratio of pearlite blocks having an equivalent circle diameter of more than 40 μm is 0.62% or less, and the difference in Vickers hardness between the surface area and a center portion is HV 20.0 or less.