Roller bearing, one of the two members of the class of rolling, or so-called antifriction, bearings (the other member of the class is the Ball Bearing). Like a ball bearing, a roller bearing has two grooved tracks, or races, but the balls are replaced by rollers. The rollers may be cylinders or truncated cones. Only radial loads (i.e., loads perpendicular to the axis of rotation) can be carried when the rollers are cylindrical, but with conical rollers both radial and thrust, or axial, loads (i.e., ones parallel to the axis of rotation) can be carried. A needle bearing has cylindrical rollers that are relatively slender and completely fill the space between the races; in many cases the inner race is dispensed with. Because there is line contact between a roller and the races, while in a ball bearing there is point contact, in a given space a roller bearing can carry a greater radial load than a ball bearing.
Roller bearings are used in all main shaft and auxiliary drive shaft applications to support pure radial load, and allow for axial shaft elongation due to temperature changes with no additional load effect on the bearing. They are usually located at the ends of the turbine and compressor shafts and are often mounted in a housing, but separated from it by a layer of pressurized oil known as a squeeze film damper. Roller Bearing,Self-Aligning Roller Bearing,Double Row Roller Bearing,Neddle Roller Bearing Shijiazhuang Longshu Mechanical & Electrical Equipment Trading Co., Ltd. , https://www.lsjgbearing.comPVC Coated barbed wire is used for security fencing
Barbed wire is used to build security fencing for livestock, private area, industrial area, warehouse or sensitive sites and to construct barrier for military fortifications. We can supply not only galvanized barbed wire, but also PVC coated barbed wire for security and protection.
PVC coated is that the wire covered with vinyl. The PVC layer not only has a positive effect on the strength and toughness of the material, but also reduces the risk of rust. It also can reduce the wear between layers when operating. PVC coated barbed wire is the ideal type for ocean engineering, irrigation machines and big excavators.
Our PVC coated barbed wire consists of 2 twisted wires with 4 spikes, spaced 65mm-120mm apart from each other.
 PVC coated barbed wire specification
Polymeric coating (green RAL 6005)Â
1. Inside wire: galvanized wire
2. PVC coating thickness: 0.4mm -0.6mm
Twisted wire diameter:Â
3. Inside wire diameter: 1.6mm -3.5mm,
4. Outside wire diameter: 2.0mm -4.0mm
5. Thorns wire diameter: 1.5mm -3.0mm.Â
6. Package: 50m, 100m, 250m, 400m/coil or 30kg-50kg/coil
 
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In many cases, instead of having a separate inner race for roller bearings, the [inner race" is an integral part of the shaft or stub shaft. This reduces complexity, weight, and build-up of concentricity tolerances. Overall, this is cost effective, but the cost of replacement or repair is likely to be higher than for separate inner races.
Model NO.: ZB-BW
Barbed Distance: 6"
Barb Length: 18mm
Coil Outside Diameter: 700mm
Color: Blue, Green
Trademark: ZB
Transport Package: Packed on Wooden Box
Specification: can be customized
Origin: China
HS Code: 7313000000
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