国色天香手机视频免费网|汤唯色戒床上未删减版|91视频大全|在线免费成人,不忠未删减完整版电影,久久性天堂,伊伊亚洲综合人网777

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