Bolt performance grade, namely the bolt performance grade for steel structure connection, is divided into more than 10 grades, such as 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9, etc.Bolt performance grade label consists of two parts, which respectively represent the nominal tensile strength value and bending strength ratio of bolt material.
The meaning of bolt performance grade is the international general standard, the bolt of the same performance grade, regardless of the difference of its material and origin, its performance is the same, the design can only choose the performance grade.
Strength grade 8.8 and 10.9 magnitude refers to the level of the shearing stress of bolt is 8.8 GPa and 10.9 GPa 8.8 nominal tensile strength of 800 n / 640 n was nominal yield strength bolts/was generally is expressed in “X.Y” strength, X * 100 = the bolt tensile strength, X * 100 * (Y / 10) = yield strength of the bolt (as stipulated in the logo: the yield/tensile strength = Y / 10, namely 0. Y showed) such as magnitude 4.8, the tensile strength of the bolt is: 400 mpa.Yield strength: 400*8/10=320MPa.Another: stainless steel bolts are usually labeled A4-70, the appearance of the A2-70, meaning otherwise explain measurements: length measuring unit in the world today there are two main types, one for the metric system, the measuring unit is meter (m), centimeters (cm), mm (mm), etc., in Europe, China and Japan and other southeast Asia use is more, another is English, the measuring unit is mainly for the inches (inch), is widely used in the United States, Britain and other European and American countries.1. Metric system measurement: 1m =100 cm=1000 mm2, English system measurement: (8) 1 inch =8 ints 1 inch =25.4 mm
Bolts used for connection of steel structures have more than 10 grades, including 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9 and 12.9.Bolt performance grade label consists of two parts, which respectively represent the nominal tensile strength value and bending strength ratio of bolt material.For example: bolts with performance rating 4.6, which means:
1. The nominal tensile strength of bolt material reaches 400MPa;
2. The bending strength ratio of bolt material is 0.6;
3. The nominal yield strength of bolt material reaches 400×0.6=240MPa class
Performance grade 10.9 high strength bolt, its material after heat treatment, can achieve:
1. The nominal tensile strength of bolt material reaches 1000MPa;
2. The bending strength ratio of bolt material is 0.9;
3. The nominal yield strength of bolt material reaches 1000×0.9=900MPa class
Post time: Mar-31-2019