The invention relates to a creping blade (1) with a blade-like main part (8) made of metal, in particular steel or stainless steel, said main part having a working edge (2) which can be placed against a drying cylinder (3) and which adjoins an end face (4) with a counter-edge (5). Grooves (6) are worked into the end face (4) and are arranged at a distance to one another, and a wear protection layer (7) is provided on the wall of the main part (9) between the working edge (2) and the main part (8), wherein the grooves (6) are worked at least into the wear protection layer (7).

A doctor apparatus for a web forming machine to doctor a moving surface, and the doctor apparatus (10) includes a doctor blade (16) and blade holder (11), which blade holder (11) has a holder component (14) preferably made of aluminum, to which the doctor blade (16) is mounted by a front plate (15), and a frame component (12) preferably made of fiber-reinforced polymer material, to which the holder component (14) is mounted. The doctor apparatus (10) having a loading element (22) arranged between the frame component (12) and holder component (14) to load the blade holder (11) and further the doctor blade (16). The invention also relates to a corresponding blade holder and holder component.

A system comprises a user computing device, e.g., smartphone, having an imaging device lens. A creping analysis module comprises a housing configured for selective coupling to the user computing device, wherein the imaging device lens is encompassed by the housing, the creping analysis module further comprising a magnifying element, a ring adapter, and a light source configured to provide a grazing angle illumination. During a calibration mode, pixels per unit length are determined from a calibration image collected via the creping analysis module at a set magnification and the grazing angle illumination via the light source. During an operating mode, crepe structure characteristics are ascertained in captured operating images comprising a tissue sheet, via the creping analysis module at the set magnification and the grazing angle illumination, and a crepe structure value is determined based on the crepe structure characteristics and the pixels per unit length.

A plurality of studs mount a doctor blade holder to a doctor back in a fiber web machine for slidable extraction of the doctor blade holder in the cross machine direction. Each stud (15) has a body (16) with a cylindrical center segment with a protruding nonround flange (17) formed as a single piece with the center segment. Opposed flats of the nonround flange of the body (16) may be engaged by the opposed parallel jaws of a conventional wrench allowing ready attachment of the studs to the doctor blade holder and subsequent installing within the channel of a rail which is mounted to the doctor back. A slide bar may be fixed to the doctor blade holder to extend out of the rail for engagement and extraction of the doctor blade holder.