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: 12CrMo4
Specifications: φ5.5~16mm
Applied Standard:  agreement
Characteristics: It's used to produce the engine vavle spring retainer
Applications: Common parts
Use of Products: 12CrMo4 is a commen steel grade which used to producethe engine vavle spring retainer. This product has characteristics of uniform-chemical composition, low percentage of harmful elements, high purity, slight decarburisation, good surface quality. After spheroidize annealing, this product has the characteristics of good cold heading properties ,stable heat-treatment properties and good hardenability