How To Improve Screening Efficiency
These current product mixes of smaller aggregate material (1”-1/4”) require much more open area within the screen to obtain the desired results. The problems caused by this are twofold:
- The bed depths of the screens are sometimes twice the acceptable bed depth, creating excessive wear and too much carryover of in-spec product;
- Screen decks can become blinded over due to the excessive bed depth and moisture of the material.
Some solutions to these problems are to monitor your bed depth and ensure that it is not four times higher than the opening of the screen cloth.
Monitoring your crusher setting will also greatly help in keeping material in spec. Daily inspections of your crusher setting (and sometimes multiple in abrasive applications) will keep the crusher at its optimal setting and aid in proper screening.
The stroke and speed of the screen are crucial to ensure that the size of the material being screened has enough g-force or speed of revolution to be screened adequately. The speeds can vary as much as 1,000 rpm for ¼” material to 600 rpm for 6” material.