| 摘要 |
<p>The spinning steel ring (1) is partially hardened, that is to say in a local area (8) of the ring wherein there is provided a traveller flange (2) with its guiding surface (3). This area (8) is comprised of an outer softer running-in layer (11) and of a hardened core (9). The running-in layer (11) comprises a superficial layer of iron nitride (7) which gradually transforms into an austenitic and martensitic transition layer (10) containing nitrogen of which the austenite contents decreases inwardly, thereby enhancing the hardness. After the iron nitride layer (7) has been worn, the traveller may slide onto the transition layer (10) of which the hardness increases gradually and which becomes more resistent as it wears. In this manner, the running in time is considerably reduced and it allows without any trouble after the running-in. The dimensions of the spinning ring (1) are strictly maintained due to the fact that the hardening is limited to the area (8).</p> |
