Being able to grind multiple materials reduces your grinding costs for everything you grind. So the more material ground the better. If you are a C&D Recycling Company for example, then you not only can separate the wood, plastics, metal and rock, but you can sort the shingles and be able to reduce your landfilling costs by lowering disposal weights. Even if you do not have an outlet for the shingles, mixing with small stone and making roads on your Landfill or site is a great option to eliminate this product after it is ground.
`But grinding shingles will wear out all the surfaces in your Grinder in a hurry and you will need a lot of water to keep the grinding chamber cool. This is the number one conversion you will need. Your radiator will plug solid with shingle dust and even dipping it may not fix it. Roofing tear off shingles are hard and brittle and the easiest to grind. Factory reject materials are much more difficult and if it is the middle of summer in the south, your ¼” ground shingle material will make one giant asphalt cone if you haven’t mixed in a little fine sand to stop it from sticking together.
There are machines specifically made to grind shingles. On these machines, there are usually:
· More replaceable wear plates
· Can be different tips
· Grinder Hammer pattern is made to keep materials away from the sidewalls of the grinding chamber to reduce wear on the outside surfaces
· Top Fed rather than force fed with feed rolls. Gives materials time to fall through screen and reduces oversize product
· Single discharge belt to reduce transfer leakage
· Conveyor Belt Splicing is different to reduce fine material leakage
· Heavy duty water spray system
among many other changes to maximize shingle reduction production.
So what do you change or what can you change to switch from grinding wood to grinding shingles? Each machine is different, some say run as is, not a good idea. Look for one that can reduce wear, increase production and is easily changed. You could purchase a shingle package grinder and then convert for wood, and then all the package options are already included. Here are some ideas:
· Adding additional wear plates
· Different rotor or rotor configuration with additional hard surfacing
· Different belt splices
· Deflector plates or screen to keep overs from mixing with finished product
· Smooth belts not chevron patterns
· Adjustable belt scrapers to keep as tight as possible to clean the belts
· Water, Water, Water. Spray bars and enough water flow to keep the grinding chamber cool
Before you invest in this additional expense, make sure you have an outlet for materials. Even better, make sure you have two outlets, so when the first one disappears, you have another option. Use as an amendment to asphalt mix is great, but when the oil price drops and it is not worth the price to buy your material, the Asphalt plant will go back to straight liquid and leave your grinder worn and wet and covered in shingle dust.
Questions? Dave Whitelaw Grinderguy@askthegrinderguy.com