... whole scrap tires into high quality, uncontaminated crumb rubber. It is uniquely designed to allow the customer to adjust the equipment screens ... Contaminant free.Maintenance:• Shredder-Allow for 20 minutes for every 8 hours of run time-tighten bolts, lubricate, and inspect• ... bolts, lubricate, and inspect• Granulators-20 minutes for every 8 hours of run time-tighten bolts, lubricate, and inspect. ...