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
亚洲精品无码专区久久久| 131美女爱做视频| 特黄熟妇丰满人妻无码| 18禁美女裸体网站无遮挡| 欧美人牲交| 亚洲 欧美 综合 另类 中字| 美丽人妻在夫前被黑人| 中文乱码字慕人妻熟女人妻| 国产在线一区二区三区av| 成人无码一区二区三区网站| 国产精品无码午夜福利| 国产精品毛片va一区二区三区| 国产色在线 | 日韩| 无码视频一区二区三区在线观看 | 国产女精品视频网站免费| www国产内插视频| 八区精品色欲人妻综合网| 精品国产一区二区三区久久久狼| 国产亚洲精品aaaa片小说| 久久久久久久综合综合狠狠| 久久精品99无色码中文字幕| 真人新婚之夜破苞第一次视频 | 国产免费午夜a无码v视频| 曰韩内射六十七十老熟女影视| 亚洲熟妇少妇任你躁在线观看无码 | 少妇无码av无码专线区大牛影院| √新版天堂资源在线资源| 国产肥熟女视频一区二区三区| 18成人片黄网站www| 国产精品久久久久久人妻| 亚洲午夜福利在线观看| 欧美疯狂做受xxxx高潮| 永久免费无码av在线网站| 国产综合精品一区二区三区| 亚洲精品乱码久久久久久蜜桃图片 | 美丽人妻在夫前被黑人| 狠狠色噜噜狠狠狠777米奇| 一本一道人人妻人人妻αv| 亚洲精品国产成人| 欧美亚洲国产成人一区二区三区| 国产伦久视频免费观看视频|