Knurled Stainless Steel Roller, Turn-Milled Hemispherical Texture, Coaxiality 0.015 mm

About This Part

This roller moves material by grip. Its outside diameter carries a dense, matrix-arranged array of hemispherical studs machined directly into the stainless body, the kind of texture used where a roller must not slip: feed rollers, drive drums and handling surfaces. The studs are cut, not cast, so the array is uniform, burr free and repeatable across the face, and across replacement rollers years apart.

Inside is the precision half of the part. The bore is held to H7 for a transition or light interference fit on the drive shaft, with stepped seats and shoulders for bearings, keys or locking hardware. Coaxiality between bore and outside diameter is held within 0.015 mm, because a roller that runs eccentric transmits that error straight into the web or belt it drives, as speed variation and tracking wander.

Machining thousands of individual studs loads the surface asymmetrically, and the resulting local forces can dent roundness if the part is chucked conventionally. The countermeasure is an expansion mandrel: the roller mounts on an internal expanding arbor so its outside can be machined without clamp-point distortion, and the finish passes come off with even, light cuts. End faces are turned square so the roller balances and seats true at speed.

Verification is instrumented. CMM takes the bore, seats, end face runout and coaxiality; an optical measuring projector checks the stud array for uniformity and form; and finished rollers run on a dynamic balance tester, because a texture roller spinning off balance shakes everything downstream of it.