Design of the shaft:
1. The material of the shaft is mainly ordinary carbon structural steel, such as C35 and C45, in addition to cast iron, ceramics, and resin plastic, but the shafts of the latter three materials have defects in sealing the seal kit.
2. Hardness. The surface hardness of the rotating shaft is generally ≥35HRC. When the medium is dirty, there are contamination impurities from the outside, or the shaft surface speed is> 12m / s, the shaft surface hardness should be above 55HRC, and the depth of the quenched layer on the shaft surface is> 0.mm.
3. Surface roughness. Because the speed of the shaft is different from the amount of oil, if the roughness of the shaft is too large or too small, it will affect the leakage and wear of the seal kit. The allowable range of the surface roughness of the shaft is Rz 1.0 to 5.0 μm; Ra 0.2 to 0.8 μm. An seal kit of 2.5 to 1.6 μm Rz was taken for the rotating shaft.
4. Shaft processing. Correct shaft processing is the decisive factor to ensure the normal operation of the sealing system. The suitable seal kit shaft processing method is horizontal feed fine grinding and emery paper polishing. The unsuitable processing methods are finishing on a lathe, super finishing, calendering, and emery paper polishing (the abrasive paper is polished by moving in the axial direction).
5. The chamfer of the shaft, the recommended value is 15 ° ~ 30 °; the principle is to allow the seal kit to be installed without damaging the lips of the seal kit.