The roll on the paper machine: structure and function

The roll on the paper machine: structure and function - 2019 03 - 7 cases of backup roll and work roll: dehydration and supporting network. Counterproposal roll requirements: light weight, flexible transmission, have enough stiffness. The structure of the roller body: case roller is a common thin-wall steel pipe roller, rubber roller surface bread, to facilitate the dehydration of slurry, corrosion resistance and reduce wear and tear of the bronze. There is also a package of glass fiber reinforced plastic, which is beneficial to reduce weight. Case the diameter of the roller: main shall ensure that the roller body has enough stiffness and speed stability, therefore is associated with the speed and width of paper machine, the higher the speed, the larger the width, the diameter of the roll should be more the case, must also be dynamic balance calibration. The case of roller bearings: 1) Commonly used rolling bearing; 2) The bearing shell should have good sealing, prevent water immersion; 3) To keep good lubrication, reduce case roller rotating friction torque; 4) Case of roller bearings in longitudinal beam orbit, can be changed according to the need to distance; 5) Case of roller bearings should be set high and low adjusting device. The dehydration mechanism of roller: dehydration effect mainly in the bronze is separated from the roller surface contact line direction along the relative established wedge in the process of negative pressure zone. On roller with copper net flow inside the wedge between the gap on roller and leads to the flow of the bronze, and cross section increases gradually. Because the water had enough cohesion, water will not be easily separated, as the result of the various points within the current traction on roller wedge formed the vacuum suction drainage on range. The suction effect is similar to the wedge interval there is a downward movement of the piston, the water pump discharge from the Internet, and then borrow case roller high-speed rotation of the centrifugal effect to water, complete dehydration process. When case roll into the contact area of the off-line aquifer is pressure at the same time, so in the role of the roller is the nature of the pulse. The higher the speed of the pulse, the greater the causes plasma surface instability even jump pulp. So the grooving roller and chopping board. Case of roll arrangement: low speed paper machine: close before they are thin. High speed paper machine: first dredging thick or thin Micronesia first after dredging. In grooved roller: role: the high speed, close to the chest roll roll a few root case with grooved roller instead. Can make dehydration, so beneficial to uniform forming of sheet. Often think: grooving width more more, the lower the dehydration ability, grooving roller in the dehydration ability only ordinary case roll 1/2 ~ 1/10. Structure: the same as the ordinary case roll, just get in the car over the surface of the roller body multichannel parallel annular groove.