Rollers are the most critical step in the cold-bending forming process. Therefore, the material selected for the roller is also a key factor in judging the quality of a roll forming machine. The selection of different rollers’ materials will cause big difference at the quality of profile and at the production cost. In the Chinese roll forming machine market, the material of the rollers is usually divided into following types: 45 steel, 45 steel electroplated with Cr, GCr15, Cr12, Cr12MOV, etc.
Many manufacturers will also change rollers to cast iron in order to save cost. Buyers need to carefully distinguish when you buy machines. Due to the different metal contents of the chemical elements C, Cr, MO, V, etc. of the above-mentioned several kinds of materials, the process performance and price are very different, so the application in production is also different. For ordinary coils with a yield strength less than 330Mpa and a thickness range less than 1.5mm, such as hot-rolled sheets, cold-rolled sheets, PPGI,galvanized steel , 45 steel or 45 steel chromed can meet the requirements. In order to prevent the rollers from rusting and prolong the service life of the rollers, Linbay Machinery apply chrome plating process to all 45 steel rollers (chrome plating thickness is 0.05mm), and the hardness after heat treatment can reach 58-62HRC, which is roughly the same as the hardness of Cr12 and GCr15. While reducing costs, it gets good quality at same time. If you want to produce high-strength coils with a yield strength greater than 350Mpa or stainless steel coils, Linbay Machinery will choose GCr15 or Cr12 as the material for the rollers, which are more expensive. These two materials have higher wear resistance, thermal stability and compressive strength, excellent overall performance. Among them, the Cr12 component is equivalent to American Standard D3. In addition to being used as a roll material, Cr12 is also commonly used as a punch, die, and insert material. The most high-quality material of the rollers is Cr12Mov or Japanese standard SKD11 or American standard D2, which is quite expensive compared with others, it has high wear resistance and has the longest service life. In addition to being used as roller’s material, Linbay Machinery usually uses this material for cutting blade.
Above all, you can choose the roller’s material according to your profile requirements and investment budget. Linbay Machinery will always give you the best solution for your specific requirements, so that you can buy a most satisfactory roll forming machine.
The main composition and performance of the rollers in the roll forming machine | ||||||||
Producing country |
Mateial model |
C content |
Cr content |
MO content |
V content |
Hardness after heat treatment |
Performance | |
China | 45 steel | 0.42%-0.5% | ≤0.25% | 56-59HRC | It has good strength and cutting performance, heat treatment to obtain a certain degree of toughness, plasticity, wear resistance, after quenching and tempering treatment, the mechanical properties are better than other medium carbon structural steels. | |||
China | GCr15 | 0.95%-1.05% | 1.3%-1.65% | 61-66HRC | High-carbon chromium bearing steelwith low alloy content, after quenching and low-temperature tempering,has high hardness, good mechanical properties, uniform structure, good fatigue and high contact fatigue performance. |
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China | Cr12 | 2.0%-2.3% | 11.0%-13% | ≥58HRC | High carbon steel has higher carbon content, so it has higher hardness, alloy elements increase hardenability, high wear resistance, but poor impact toughness. |
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China | Cr12MOV | 1.45%-1.7% | 11.0%-12.5% | 0.4%-0.6% | 0.15%-0.3 | ≥60HRC | V can refine the grain of steel, improve hardenability and thermal strength, maintain strength and sufficient resistance to deformation at high temperatures; Cr can increase strength and toughness, and combine with C to form carbides,which can be used under high temperature and pressure It can improve the hydrogen corrosion resistance;hardenability, hardness after quenching and tempering, wear resistance and strength are higher than Cr12, used to make various cold punching dies. |
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Japan | SKD11 | 1.4%-1.6% | 11%-13% | 0.8%-1.2% | 0.2%-0.5% | >62HRC | Corresponding to China’s Cr12MOV, and US D2 | |
US | D2 | 1.4%-1.6% | 11.0%-13% | 0.7%-1.2% | 0.80% | ≥60HRC | Corresponding to China’s Cr12Mov, and Japan’s SKD11 |
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US | D3 | 2%-2.35% | 11%-13.5% | 60-62HRC | Corresponding to China’s Cr12 |
Post time: Aug-27-2020