The number on the bolt refers to the strength level. For example, the number 4.8 means that the strength level of the bolt is 4.8, and its shear stress is 4.8 GPa. According to regulations, bolts with a strength grade of 8.8 or higher are collectively called high-strength bolts, and the rest are collectively called ordinary bolts. General bolts use "XY" to indicate the strength, X*100=the tensile strength of this bolt, X*100*(Y/10)=the yield strength of this bolt (because according to the label: yield strength/tensile strength =Y/10). For example, grade 4.8, the tensile strength of this bolt is 400MPa; the yield strength is 400*8/10=320MPa.
Bolts that are made of high-strength steel or require a larger pre-tightening force can be called high-strength bolts. High-strength bolts are mostly used for the connection of bridges, rails, high-pressure and ultra-high pressure equipment. The fracture of this kind of bolt is mostly brittle fracture. High-strength bolts applied to ultra-high pressure equipment need to be prestressed in order to ensure the tightness of the container.
Three Identification Of Drum Closure QualityJune 30, 2022Three identification of drum closure quality1. large welding points of plugsThe welding points of plug is used to stick the attachment on the body of plug, and prevent it from falling over during open...view
Tangshan Steel City Piaohong, Steel Prices Still Have Room To Rise Next WeekJuly 1, 2022This week the spot market as a whole mainstream price shock up.With the performance of raw materials and futures, the spot market mentality was boosted, coupled with the actual transaction performance...view
Performance Characteristics of Steel DrumsJuly 17, 2023Although the application of steel drums has only a history of more than 100 years, it has developed rapidly and has a wide variety of varieties, which are widely used in industrial product packaging, ...view
Global Shipping System Under The Impact Of The EpidemicJune 30, 2022What has happened to the global shipping system under the impact of the epidemic?1. "Crazy" shipping priceIn the winter of novel corona virus pneumonia, besides the hot vaccine industry, the...view
The Price Trend Of Cold-rolled SteelJuly 1, 2022Cold-rolled coil: On April 8th, the average price of 1.0mm cold coil in 24 major cities in China was CNY 6,047 / ton, down CNY 11 / ton compared with the last trading day. This week, the weekly output...view
A Guide to Steel DrumsJune 16, 2023Steel drums are some of the most versatile and robust containers in popular usage throughout many industrial and commercial sectors. They can be found in warehouses and transport depots across the wor...view
EN
ko 
fr 
de 
es 
it 
ru 
pt 
ar 
vi 
th 
