Printing material web processing machine

摘要

A printing material web processing machine, in particular a web-fed rotary offset press, has at least one press cylinder for printing the web, a dryer disposed downstream of the press cylinder, which guides the web along a path, and at least a first pull roll disposed downstream of the dryer to convey the web along the path with a given tensile stress. The web processing machine further has a first apparatus disposed downstream of the press cylinder and upstream of the dryer for separating the web from the press cylinder, and a second apparatus for driving the first pull roll, which drives the first pull roll at a rotational speed that is reduced as compared with the rotational speed of the press cylinder.

主权项

1. A web-fed rotary printing press, comprising:
at least one press cylinder for printing a paper web conveyed at a controllable first tensile stress; a dryer disposed downstream of said press cylinder, said dryer including a plurality of nozzle bars disposed on both sides of the web guiding the web along a meander-like path, the nozzle bars being spaced apart and offset from one another; a pull roll disposed downstream of said dryer for conveying the paper web along said meander-like path under a second tensile stress; a first apparatus disposed downstream of said press cylinder and upstream of said dryer for separating the paper web from said press cylinder during a normal printing operation, said separating of the paper web from said press cylinder being decoupled from the conveying of said paper web along said path; a second apparatus for driving said pull roll at a controllable rotational speed which sets said second tensile stress; and a controller coupled to said at least one press cylinder and to said second apparatus, said controller setting said first tensile stress and said second tensile stress such that said second tensile stress is less than said first tensile stress.