Understanding the working conditions and principles of welded pipe rolls
Do you know before you buy? The working process of welded pipe rolls. Today by the welded pipe roll manufacturer to introduce you.
Determined by three factors.
① rolling mill, rolling material and rolling conditions, as well as a reasonable choice of rolls.
② roll material and its manufacturing quality.
③ roll use and maintenance system.
Strength, thermal crack resistance.
Usually the main requirement for rough rolls is strength and thermal crack resistance; the working roll of a small 20-roller mill weighs only about 100 grams, while the weight of the support roll of a wide plate mill has exceeded 200 tons. When selecting rolls, first according to the basic strength requirements of the mill for rolls, selected to safely carry the main material (various grades of cast iron, cast steel or forged steel, etc.).
Hardness, wear resistance.
And finishing rolls with high speed, rolling the final product to have a certain surface quality, for it to hardness, wear resistance, etc. as the main requirements. Then consider the rolls should be used when the wear resistance. As the wear mechanism of the roll is very complex, including the mechanical stress effect, rolling when the thermal effect, cooling effect, the chemical effect of lubricating medium and other effects, there is no a comprehensive assessment of the roll anti-wear unified indicators. Since hardness is easy to measure and can reflect wear resistance under certain conditions, the radial hardness curve is generally used to approximate the wear resistance of rolls.
In addition, there are some special requirements for rolls, such as the amount of pressure down, the rolls are required to have a strong bite into the ability, more resistant to impact.
Rolling thin specification products, the rigidity of the roll, the uniformity of the tissue properties, processing accuracy and surface finish requirements are more stringent.
When rolling complex sections of steel, also consider the cutting performance of the working layer of the roll body.
Selection of rolls, some of the performance requirements of the rolls are often opposed to each other, roll purchase and maintenance costs and very expensive, so should be fully weighed against the technical and economic advantages and disadvantages of the decision to use cast or forged, alloy or non-alloy, a single material or composite materials.