Stretching nip rolls, stretching nip press to use the stretching nip rolls, papermaking machine and method of operation of the stretching nip press

摘要

The present invention is a stretching nip roll (5) capable of forming a press nip (N) with respect to a counter roll (7), wherein the stretching nip roll (5) is a counter roll (7). Relates to a stretching nip roll having a length in the flow direction when cooperating with. The stretching nip roll (5) includes a flexible jacket and an elastic press body (13) disposed inside the flexible jacket. The top (14) of the press body (13) is chamfered so that the working surface (15) of the top has a downstream end (16) in the flow direction, and the downstream end (16) Is followed in the flow direction by an outlet side surface (17) which branches off from the inner surface (11) of the flexible jacket (10). The press body (13) further includes at least first and second internal pressure chambers (18, 19). The pressure chambers (18, 19) can be pressurized so that the press body (13) expands. The first internal pressure chamber (18) has a length in the flow direction that does not extend beyond the working surface (15), and the second internal pressure chamber (19) is the first internal pressure chamber (18). And has a length in the flow direction that extends beyond the downstream end (16) of the working surface (15). The working surface (15) and the outlet side surface (17) are made of a material having a Shore A hardness higher than the Shore A hardness of the material of the remaining portion of the press body (13). The present invention also relates to a stretching nip press and a papermaking machine in which the stretching nip roll is used. Furthermore, the present invention relates to a method for operating the stretching nip press.