Apparatus for dewatering fiber suspension for producing a web of fiber

Apparatus for dewatering a suspension of fibers comprising:

• a first strip movable through a dewatering region;
• first support means for moving said first strip on a convex pathway through the dewatering region and for maintaining longitudinal tension of said first strip;
• said first support means comprising a stationary support which is convexly curved and over and with respect to which said first strip is moved;
• said first support means including means for moving said first strip over said stationary support;
• a second strip movable together with said first strip through the dewatering region;
• second support means for moving said second strip along a concave pathway through the dewatering region and for moving said second strip spaced from said first strip and for also maintaining the longitudinal tension of said second strip;
• at least one said strip being water permeable;
• for eliminating pressure gradients in the suspension held between said strips passing through the dewatering region, said second support means being shaped for maintaining the radius of curvature of said second strip at a value at which the radius of curvature at every point along said second strip substantially is:
• ##EQU2## where S is the tension of said second strip established by said second support means therefor;
• p.sub.o is the dynamic pressure of the suspension in the intake between said strips where the suspension first contacts both said strips;
• .rho. is the density of the suspension;
• g is the acceleration due to gravity;
• h is the actual vertical height or distance between the point on said second strip at which the radius is being measured and the point on said second strip at which the suspension first contacts both said strips.