精密管-火爆预定中

The popularization and application of high-precision pipes saves steel, improves processing efficiency and saves energy. The so-called high-precision cold-drawn pipe refers to the internal and external diameter precision (tolerance range) is strict, good surface finish, good roundness, uniform wall thickness of cold-drawn pipe. The main technical indexes of the high precision cold drawn tube produced by this technology reach the expected goal. Details are shown in the following table: the main technical indicators and the standard control table items have actually reached the GB8713-88 ISO4394 internal diameter tolerance H8 H9 H8 H8 H8 H8 H8 H8 H8 H8 H9 H9 H10 straightness 0.3 > 0.5/1000B wall thickness deviation roundness汽车半轴套管用无缝钢管（GB3088-82）是制造汽车半轴套管及驱动桥桥壳轴管用的优质碳素结构钢和合金结构钢热轧无缝钢管。德威花园城一期占地约 这是它的柴油机用高压油管（GB3093-86）是制造柴油机喷射系统高压管用的冷拔无缝钢管。精密管或冷轧精密无缝管(GB3639-2000)是机械结构和液压设备用尺寸精度高、表面光洁度好的冷拔或冷轧精密无缝管。高精度精密管是一种新型的高技术节能产品。

添加钛、铌等微合金元素形成弥散的氮化物或碳氮化物，导致冷轧精密光亮钢管的韧脆转变温度升高。(3)晶粒尺寸对韧脆转变温度有影响，随着晶粒粗化，韧脆转变温度升高。冷轧和精密光亮钢管的晶粒脆化倾向得到了广泛的应用。高春铁（0.01% C）的Tc在该温度以下的100C完全易碎。冷轧精密光亮钢管中大部分合金元素都提高了韧脆转变温度和冷脆倾向。室温以上发生韧性断裂时，冷轧精密光亮钢管的断口为韧窝断裂，低温脆性断裂时断口为解理断裂。

Following the decline in crude steel production in the first ten days of this month, crude steel production rose again in the first ten days of this month. Inventories of heat preservation and anticorrosion pipe manufacturers and factories also declined. The production situation of secondary or steel plants is not clear. At present, as raw material prices continue to fall, consumer enterprises still have profit margins; coupled with financial pressure, most steel mills need to maintain operation in order to continue to obtain savings; therefore, steel mills still adhere to a higher start-up rate; Anshan region, for example, as of this month, Tangshan blast high production capacity application rate. Up to.0%, the rate of increase was normal.