Zhengzhou wholesale mining screw with a ball screw ball mill liner pad combination wholesale Siwa

Doo-bolts level ???? Do 400X0.8 = 320MPa Grade 1 Chinese name Doo-bolt English name: bucket-type bolt 2 is defined by the head and screw (threaded cylinder) whose head is shaped hopper a class of fasteners science: ball screw (a subject) Doo-bolts (two subjects); fasteners (three subjects); 3 Wikipedia card Doo-bolts [1] Doo-bolts: Use in a ball, a class of non-standard fasteners crusher liner on. The bolt head by a positive bevel, the screw thread (externally threaded cylinder) composition. Performance Level 4 performance level and meaning Doo-bolts can be divided into a total of 10 personality can 3.6,4.6,4.8,5.6,5.8,6.8,8.8,9.8,10.9,12.9 grade, where 8.8 (or more) for the strength of the bolt material heat-treated carbon steel and alloy steel, high strength bolts bolts called, and the rest is known as the general strength of the bolt. Bolt performance rating label has two parts numbers, respectively bolt nominal yield strength and tensile strength ratio. For example: a performance grade 4.8 bolts, and its meaning is: (1), bolt material nominal tensile strength up to 400MPa grade; (2), bolt material yield strength ratio is 0.8; (3), the nominal bolt material 400X0.8 = 320MPa yield strength up to level 2, the performance level of 8.8 bolts, and its meaning is: (1), bolt material nominal tensile strength up to 800MPa grade; (2), bolt material yield strength ratio is 0.8; ( 3), the nominal bolt material yield strength of 800X0.8 = 640MPa grade 3, grade 10.9 bolts performance, and its meaning is: (1), bolt material nominal tensile strength up to 1000MPa level; (2), the bolt material yield ratio of 0.9; (3), the nominal bolt material yield strength of the bolt 1000X0.9 = 900MPa grade performance levels of meaning is the international standard, the same performance level of the bolt, the difference between matter and the origin of the material, its performance is the same, the design performance levels can use only. Bolt strength rating of 10.9 means the bolts shear stress level is 10.9GPa. 5 types of bombs supporting a bolt + nut + pad + pad 2, bolt + nut + washer + cylindrical rubber three steps, bolt + nut + washer + O chamfered rubber gasket