婷婷五月伊人,亚洲国产精品免费,日韩午夜福利在线观看,一区二区午夜按摩,久久精品国产免费,国产免费a级片全部,成人黄片在线播放

Main Products
Products Grade: 55SiCrA,55SiCrA-1
Specifications: φ5.5-22mm
Applied Standard:  agreement
Characteristics: suspension spring\valve spring\mechanical spring
Applications: Suspension spring steelSpring steel
Use of Products: The wire rod of 55SiCrA, which is common steel grade to produce suspension spring and valve spring widely used in automobile and motorcycle Industries, has characteristics of uniform-chemical composition, low gas content and harmful elements, high purity, slight decarburisation, good surface quality and drawability as well as consistent heat-treatment quality.