Adding one centerless grinding process after the carbide rod blank coming out of sintering furnace, we get the ground carbide rod. If there is a further special length requirement, a cutting process should be done before grinding, then we get the cut-to-length ground carbide rods. Cut-to-length carbide rod blank also can be available.
According to the different grinding degree of the outer dia. of carbide rod, there are h grades and H grades tolerance, h grades referring to minus diameter tolerance, H grades referring to plus diameter tolerance. Most general ground degree requirement is h6, and Betalent carbide also can make h4, h5 degree. The below sheet listing the detailed tolerance of h4,h5, and h6.
Diameter | h4 | h5 | h6 |
0<D<3mm | 0.003mm | 0.004mm | 0.006mm |
0<D<O.1181in | 0.00012in | 0.00015in | 0.00024in |
3<D<6mm | 0.004mm | 0.005mm | 0.008mm |
0.11812<D<O.23622in | 0.00016in | 0.00020in | 0.00024in |
6<D<10.0mm | 0.004mm | 0.006mm | 0.009mm |
0.23623<D<O.3937in | 0.00016in | 0.00024in | 0.00035in |
10<D< 18.0mm | 0.005mm | 0.008mm | 0.011mm |
0.39371<D<O.70866in | 0.00020in | 0.0003in | 0.00043in |
18<D< 30.0mm | 0.006mm | 0.009mm | 0.013mm |
0.90867<D<1.1811in | 0.00024in | 0.00035in | 0.0005in |
30<D<50mm | 0.007mm | 0.011mm | 0.016mm |
1.8111<D<1.9685in | 0.00028in | 0.00043in | 0.00063in |
Besides diameter tolerance, roundness is another key factor to measure the grinding quality of a ground carbide rod, for long rods(330mm or 310mm), Betalent standard for roundness is within 0.005mm, for short cut-to-length carbide rods, roundness is within 0.003mm. For extreme requirements, that figure can be controlled to 0.003mm and 0.001mm.
To be applied as end mill raw material, common cut-to-length carbide rods lengths are 50mm, 60mm,75mm, 100mm, and 150mm.