国产亚洲精品自在久久,野花香社区在线视频观看播放,а√天堂中文在线资源bt在线,日韩人妻高清精品专区

tangshan tiankun metal tool manufacturing co., ltd
搜索
首頁

current location:

Homepage >  News Center: Tips: the industry news is meaningful to update every day
tangshan tiankun metal tools co., ltd News Center

tangshan steel shovel
tangshan steel shovel

luannan county is located in the core area of bohai economic circle and beijing tianjin hebei metropolitan area, with complete infrastructure. luannan county is a famous steel spade production base, with an annual production of more than 300 million steel spades and hardware tools, accounting for 90% of the country's export volume, and an annual export of 80 million us dollars. in recent years, luannan county, hebei province, the "hometown of steel spade", has guided enterprises to increase product research and development, and promoted the development and upgrading of steel spade industry. at present, there are 182 steel spade enterprises in the county, and the products are exported to more than 140 countries and regions.

time:2021.01.11.10:35
quality of steel spade
quality of steel spade

as a kind of common metal products, steel spade is widely used in agriculture, construction and other industries. the quality of steel spade depends on the production process and heat treatment process of steel spade. the heat treatment process of steel includes annealing, normalizing, quenching and tempering and surface heat treatment. tempering includes high temperature tempering, medium temperature tempering and low temperature tempering. tempering is to reheat the quenched steel to a certain temperature and then cool it by a certain method. its purpose is to eliminate the internal stress produced by quenching, reduce the hardness and brittleness, so as to achieve the expected mechanical properties.

time:2021.01.11.10:36
steel shovel town
steel shovel town

luannan county takes the transformation and upgrading, innovation and development as the main line to make the traditional characteristic industry bigger and stronger. through the transformation of mode and structure, it constantly innovates the reform ideas and measures, builds the steel shovel town with high quality, focuses on promoting the high-quality development of the steel shovel industry, and drives the traditional characteristic industry to radiate new vitality. recently, the provincial development and reform commission announced the list of the first batch of characteristic towns in hebei province (jite town lianban [2017] no. 1). luannan county, china steel shovel town on the list of cultivation category.

time:2021.01.11.10:37
日本50岁丰满熟妇xxxx| 樱桃视频影院在线播放| 色橹橹欧美在线观看视频高清| 国产成人a视频高清在线观看| 8ⅹ8x擦拨擦拨成人免费视频| 一边做一边说国语对白| 西西午夜无码大胆啪啪国模| 蜜臀av无码人妻精品| 公和我做好爽添厨房| 人人妻人人添人人爽欧美一区 | 久久亚洲av无码精品色午夜麻豆| 午夜性色一区二区三区不卡视频| 免费无码一区二区三区蜜桃| 国产精品免费观看久久| 欧美午夜一区二区福利视频| 三男一女吃奶添下面| 高h小月被几个老头调教| 精品无码人妻一区二区三区| 成品人视频ww入口| 天天干夜夜操| 国产成人亚洲精品青草天美| 少妇下面好紧好多水真爽播放| 女人高潮内射99精品| 国产精品扒开腿做爽爽爽视频| 99久久精品国产一区二区蜜芽| 日本丰满熟妇videossex8k| 国产中老年妇女精品| 免费又黄又爽又猛的毛片| 午夜免费福利小电影| 中文字幕亚洲乱码熟女一区二区| 国产精品无码一区二区三区在| 亚洲精品456在线播放| 国产av无码久久精品| 人妻体内射精一区二区| 香港三日本三级少妇三级视频| 国产一区二区精品久久岳| 99久久无码一区人妻| 亚洲av日韩综合一区二区三区 | 久久久久免费看成人影片| 亚洲一区爱区精品无码| 色老板美国在线观看|