| 摘要 |
<p>The roll has a peripheral surface coating formed by a helical winding of one or more metal strips, which are fixed at their ends to the roll body and possibly also at intermediate points. The helical turns are pref. sepd. by gaps, the strip being spot welded at intervals to the roll body. Alternatively, the turns may be in contact and spot welds used to join adjacent turns and include the roll body in the spot weld. The metal strip is pref. 5-15 mm. thick and (a) several strips may be rolled in helices with the same direction and pitch; or (b) at least two strips can be rolled in opposite directions, to form helices which are symmetrical w.r.t. the roll section. Guide and suport rolls are subjected to pronounced thermal stress which causes cracking and fracture of the rolls. The invention provides roll peripheries which can expand and contact when exposed to thermal stresses, thus preventing roll fracture.</p> |
