Views:10 Author:Site Editor Publish Time: 2021-01-24 Origin:Site
According to National Standard GB/T230.2, rockwell hardness of 8 grade Lug nut must be HRC23-32.
Sometimes the product hardness is too high, will affect his flexibility, easy to break, so our factory's 8-class lug nut, rockwell hardness control in HRC25-29.
How do I detect rockwell hardness of an 8-class Lug nut?
1. First of all, the surface of the product coating removed, because the coating is not hardness, will affect the accuracy of the test, so the surface of the product to be ground into a plane, exposing the steel inside.
2. Place the Lug nut on the table.
3. Rotate the platform to bring the product into contact with the detector. Make sure the little pointer is aligned with the red dot.
4. Rotate the dial so that the big pointer is aimed at the letter "C"
5. pull the first switch on the right side so that the detector presses down hard on the product.
6. Push the second switch on the right and release the force of the probe.
7. Read the data to determine eligibility.
1．the nuts and bolts of the testing method is the same, but the HRC standard is not the same, different grades, different HRC standard.
2. In addition to Rockwell hardness testing, load retention testing is required to determine the mechanical properties of Lug nut and Lug Bolt. Next time, we'll show you how to test the payload.