Abrasion In Refractory
R-MAX products were developed by Resco for its petroleum refinery market. The technology features abrasion-resistant aggregates in an extremely strong matrix. We have developed a variety of compositions for mineral processing applications in the R-MAX product family.
Our general service R-MAX products are listed here. The C suffix indicates a casting-only material. A G suffix indicates that that product is only suitable for gunning. Note that the abrasion test numbers are higher for the gunning mixes. This is because we do the abrasion plates by casting in the lab. These gunning mixes cast poorly in the laboratory and require more water than casting grades, which yields more abrasion in the C-704 test. We expect that the abrasion resistance of a gunned R-MAX lining will be better than what the cast sample laboratory tests indicate. The QT suffix indicates that the product contains QUIKTURN technology for fast dry outs. PC suffixes indicate pump casting grades, also useful for shotcrete linings.
The two photos below show one of the first R-MAX linings in a long rotary pebble lime kiln, the extreme feed end in a heat exchanger zone. Remember the heat exchanger location gets my most severe abrasion rating at a 6. After 15 months the lining looked great, a bit polished, and you can easily see the marks from the form boards. This lining was vibration cast at between 4.5% to 5% water using R-MAX C.
After 27 months, the same lining is still in great shape, although the cold joints at the edges of the pours are more pronounced. This lining is ready to give several more years of service.
Just for comparison, here are abrasion plates for R-MAX PC QT and R-MAX PC. The R-MAX PC gives an excellent result, but in comparison, the R-MAX PC QT looks a bit better. Returning to the water content for mixing, the standard water content for testing R-MAX PC is 6.5%, which is for pumping consistency and is what the plate on the right was cast at. The R-MAX PC QT in this case was cast at a lower 5% water, typical for vibration casting. Visually you can see the importance of water content for abrasion resistance.
Resco offers several R-MAX products that combine abrasion and build-up resistance by modifying the aggregates and additives. R-MAX CZ is a casting-only grade with a zircon addition for helping to manage moderate build-ups. It is often used on burner pipes in cement kilns. We offer a zircon-containing gunning mix version for moderate build-up resistance, R-MAX ZG QT. R-MAX Z PC QT offers moderate build-up resistance, shotcrete capability, and fast dry-outs. Our newest product, R-MAX AZS PC QT, is for more serious build-up locations and includes shotcrete and fast dry-out capabilities.
What Imparts Good Abrasion Resistance
- Hard, abrasive refractory grains
- An engineered matrix to achieve low water content and good flow
- A strong bond between the matrix and the refractory grains
- Low water content on installation
We encourage you to look to Resco for assistance in solving your abrasion problems and suggest that you try one of our R-MAX products. The R-MAX products continue to impress me as they handle the most severe abrasion applications. Thank you for participating.