亚洲最黄视频-亚洲最大在线-亚洲最大网址-亚洲最大色网-亚洲最大色视频-亚洲最大情网站在线观看

U-shaped steel

U-shaped steel

DESCRIPTION

U-shaped steel (full name: mine roadway support hot-rolled U-shaped steel) U-section steel is a type of steel with a cross-section like the letter U, sometimes with a cross-section in the shape of the


DETAILS

U-shaped steel (full name: mine roadway support hot-rolled U-shaped steel)
U-section steel is a type of steel with a cross-section like the letter "U," sometimes with a cross-section in the shape of the Japanese letter "ひ."
The latest standard was released in 2008, on April 1, 2009 implementation of the national recommended standards
GB / T 4697-2008
U-shaped steel bracket
Main features: under pressure, support a long time, easy to install and easy deformation characteristics.
Main purposes: Mainly used for mine roadway, mine roadway secondary support, as well as supporting the use of tunnel support and other purposes.
As the main section steel for making tunnel scalable metal stents, U-section steels are widely used both at home and abroad.
However, due to the inconsistent understanding of the properties and requirements of the U-shaped steel, the cross-sectional shapes, geometrical parameters and materials of U-shaped steel in various countries are not the same.
China's U-shaped steel production models are mainly 18U, 25U, 29U, 36U four. One of the first two of the Department of 60's products, is a waist positioning; the latter two are 80's products, is the ear location. U18 is rarely produced due to its low carrying capacity.
In GB / T 4697-2008 in addition to the above four models of U-shaped steel, the new 40U this model.
The weight of each type of U-beam is as follows:
18UY 18.96 kg / m
25UY 24.76 kg / m
25U 24.95 kg / m
29U 29 kg / m
36U 35.87 kg / m
40U 40.05 kg / m
After the model with "Y" said for the waist positioning.
U-type steel varieties: cold-formed U-shaped steel, large U-shaped steel, U-shaped steel for automobiles, hot dip galvanized U-shaped steel and other open cold-formed steel.

RELATED PRODUCTS

成人高清免费无码毛片 | 成人影片免费在线观看 | 成人小说亚洲一区二区三区 | 91yeyeairiri | 东北女人无套内谢毛片 | 无码人妻丰满熟妇奶水区码 | 久久亚洲综合影院蜜臀 | 中文字幕一区二区人妻痴汉电车 | 无码粉嫩小泬无套色欲人妻 | 日韩专区 欧美专区 | 精品无码一区二区人妻久久蜜桃 | 日韩的一区二区三区四区五区视频 | 亚洲色情一二三区 | av高清无码在线观看 | 亚洲乱码一级婬乱A片3A片 | 人妻无码免费视频 | 中文字幕永久区乱码六区 | 欧美写真视频一区 | www.免费视频 黑料 | 熟女A片精品一区二区免费看 | 91精品少妇高潮一区二区三区不卡 | 亚洲AV无码乱码A片秀色直播 | 日本有码在线播放 | 国产伦精品一区二区三区免费视频 | 亚洲 日韩 国产 成人 另类 | 亚洲成色www成人网站妖精 | 丁香九九九九九综合视频 | 亚洲AV成人一区二区三区在线 | 欧美人穴高清视频在线播放 | 四色永久网站地址 | 国产精品欧美一区二区 | 美女被玩弄出水来 | 国产人妻精品午夜福利免费 | 午夜福制92视频1000集 | 福利柠檬成人aⅴ导航 | 亚洲无码在线免费观看视频 | 丰满人妻少妇久久久久久久久久久久 | 韩国无码在线观看 | 亚洲一区二区三区免费 | 91在线无码精品秘 入口九色十 | 久久夜色精品国产欧美乱极品足浴 |