Operation & Maintenance
Back-Pressure Adjustment
Setting final cake compression at the discharge
The back-pressure device at the discharge end controls how hard the cake is compressed before it leaves the machine. More back pressure raises cake solids up to a point; too much can extrude solids into the filtrate or overload the drive.
How back pressure shapes the cake
As sludge reaches the discharge end, the narrowing screw pitch and the back-pressure plate or cone form a plug of cake that seals the machine and allows compression. Increasing back pressure tightens this plug, squeezing out more water and raising cake solids. Beyond an optimum, further pressure forces fine solids back through the screen into the filtrate and increases screw torque without improving dryness.
Tuning back pressure
- 1Confirm polymer and screw speed are already set
Back pressure is the final trim, not the first control.
- 2Increase back pressure in small increments
Watch cake solids rise and filtrate stay clear.
- 3Stop when filtrate starts to cloud or torque climbs
That marks the practical maximum; back off slightly.
RF Series Screw Press
Self-Cleaning Ring Disc Filter Elements
Fixed and moving stainless steel rings form the filtration gaps and keep them clear continuously — no filter cloth, no clogging.
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