Schedule a Call Back
Hydraulic Swimming Rolls
Hydraulic Swimming Rolls
Unique Machine Systems offers high tech Hydraulic Swimming Rolls. The basic principle underlying swimming calender rolls and swimming press rolls are same. Material of construction, finish, surface coating and values of PLI are quite different to meet specific requirement of pressing the water out of the web. Shell of the roll may be made of alloy cast iron, alloy steel or stainless steel with or without rubber covering. Instead of applying hydraulic oil at one common pressure, many sub-pistons are fitted inside the roll and pressure acting under each piston can be controlled from outside. This enables the operator to profile the moisture to suit web condition and environmental conditions (edges loosing more moisture, etc), different to meet specific requirement of pressing the water out of the web. Piston shoes work as per "hydrostatic principles" and so there will be no metal-to-metal contact between rotating shell and stationary piston and hence no wear at sliding surfaces. Generally, one side of the sheet is usually in contact with a smooth, hard roll, with or without hard rubber covering. The roll in contact with the felt is usually covered with somewhat resilient rubber cover to soften the nip. The top roll is mechanically loaded by pneumatic or hydraulic cylinders to create the desired pressure at the nip. Same paper machine is called upon to manufacture different weight and grades of paper. A fixed crown (obtained by grinding the roll) is suitable only for one nip load condition, i.e., only for one grade of paper. "Swim rolls" and more precisely "hydraulic swim rolls" enable the operator to set the exact value of crown or profile to deliver a reasonably level moisture-profile into the dryer section.
