Hex flange head bolt DIN6921
We have our own surface treatment plant, and the thickness of zinc layer meets the standard requirements. We can make authoritative inspection reports, including surface treatment such as hot galvanizing, Dacromet, electro galvanizing, boiling black, etc.
The outer hexagon screw is a matching nut used to fasten and connect two connected parts with through holes and components. Hex head screws are commonly used bolts. It is more important to use Class A and Class B outer hexagon. In addition, it is often used in the occasion of high assembly accuracy, large impact, vibration or cross rate load. Grade C outer 66 screws are used in situations where the surface is rough and the assembly accuracy is not required.
GB series, Q standard series, DIN German standard series, IFI American standard series, BS British standard series, JIS Japanese standard series, ISO international standard series, etc.
One of the standards for hexagon bolts is the level standard, which is divided into 4.8 and 8.8. These two levels are used more frequently in the market. Especially Grade 4.8 outer hexagon bolt. Because it is much cheaper than grade 8.8 hex bolts. Of course, it is more widely used. But for products with high requirements. Because of its high requirements in hardness and other aspects.
The material comes from a high-quality steel manufacturer, which can issue an authoritative material inspection report, including Q235, 35 #, 45 #, 345B, 40Cr, 35CrmoA, stainless steel 201, 304 and other special materials.
This requires the use of grade 8.8 hex bolts. Grade 8.8 outer hexagon bolt is harder in terms of hardness and screw torque. It is safer to use the product. Faster and more stable.
