BCR - Boral Bricks Revamps Plant 3
In the late ’90s, Boral Bricks decided to streamline its operations. One plant would focus on making all of Boral’s architectural brick, allowing all the other plants to focus on residential. The Augusta plant’s central location, ready access to a large supply of raw materials and the availability of transportation systems made it a prime choice for the architectural product line. Boral decided to modify the plant to handle the architectural brick production while doubling the plant’s capacity to about 90 million brick per year.
Computerizing Clay Prep
The first step in updating Plant 3 was the clay preparation facility. The existing raw clay crude storage shed, which held shale and kaolin, was too small. The company added 100 ft to the shed to ensure that fewer mining cycles would be required and that the material in the shed would stay dry.Next, the plant replaced its old McLanahan Pioneer crusher, built in the ’50s, with a new JC Steele double roll primary crusher. “With the McLanahan crusher, we were probably getting 4 or 5 in. particles—about grapefruit size—and we were counting on our grinding system to take those particles all the way down to -8 mesh,” said Gary Kennamer, regional quality manager. “This put a lot of wear and tear on our equipment, and it wasn’t efficient—we weren’t getting the tonnage we needed out of our grinding and screening system. The new crusher greatly reduces the particle size to no larger than 11⁄2 to 2 in. in diameter—about the size of golf balls. Doing the majority of our primary crushing through the double roll crusher helped our grinder put out more tonnage per hour of grinding and helped make the batching of the materials much more accurate.”
The company chose the JC Steele double roll primary crusher for its reputation in the industry, as well as for its versatility. “We use the crusher for shale, which is very hard, as well as kaolin, which can be very soft and sticky—almost muddy sometimes. We needed a crusher that could handle these different types of raw materials,” Kennamer said.
A new batching system was next on the company’s list. The original system, supplied by Inglett & Co. (Augusta, Ga.) when the plant was first built, used mechanical balance beam scales. When a certain amount of material was on the scale, the system would hit a limit switch and shut off the belt that was feeding it, then dump its material into the batch. Switching among the company’s 10 different batching formulas was a labor-intensive, time-consuming process. Employees had to set the weights manually by sliding them along the balance beam, and inaccuracies were common. When the belt stopped, large particles often continued to fall into the batch, making it overflow. While the new primary crusher helped, it didn’t solve all of the problems, so Boral asked Inglett to update the entire batching system.
Inglett replaced the old mechanical balance beam system with four 4-cu.-ft. hoppers. Each hopper has 1000 lb load cells on each corner to ensure that batches remain accurate to 1⁄10 of a pound. Additionally, all weights and formulas are programmable through a PC using Fastrac III software. “To change a formula, we simply punch a few buttons and we’re ready to go. The accuracy and color consistency of the new system is way beyond anything we could have imagined,” Kennamer said.
Using the new batching system, Plant 3 can print out statistical reports that show the average weights of each hopper and the average deviations. This enables the plant to keep a close eye on the quality of its products. The system is also self-calibrating to ensure that the weight of each batch remains accurate. “The computer watches the batching process, and if it runs so many batches that are considered ‘out of control’—either above or below the desired weight—it will automatically put itself in standby mode, drop its own calibration weights, which are in the load cells, recalibrate itself, and then turn itself back on. It does a better job than any person could do on it,” Kennamer said.
After going through the batching system, material next moves to the hammermill. Plant 3 replaced an old rim discharge grinder with a JC Steele hammermill to further increase its efficiency. A closed-loop circuit between the hammermill and eight 8-mesh screens ensure that all material is ground to –8 mesh before it heads into the manufacturing facility.
Through these modifications, Plant 3 was able to increase its grinding capacity from 45 to 70 tons per hour. The plant is currently investigating new screens that will enable it to reach a 100-ton-per-hour grinding capacity. “Right now, our batching system and grinder will handle 100 tons per hour, but the screen capacity creates a bottleneck. Replacing the screens should solve that problem,” Kennamer said.
Modernizing Manufacturing
Once the grinding plant had been updated, the company began evaluating its needs in the manufacturing facility. Two rebuilt JC Steele 90 brick machines were installed to handle the increased production of architectural brick. Both machines feature quick-change dies that allow the company to easily switch between product lines. “We run a lot of solids, and we used to have to open the head of the brick machine up, dig it out, take the bridge out, close it up, run the solids, open it back up, dig it out, put the bridge back in and reset the bridge. It took us about two hours to run two cars of solid brick. With the new brick machines, we can change over and run solids and then change back in 20 seconds—all we have to do is switch the head over and it starts right back up,” said Carl Williamson, Plant 3 manager.While the two tunnel kilns were still in good condition, the old Pearne & Lacey setting machines were slow and outdated, and prevented the plant from getting enough product through the kilns. Boral Bricks had had some experience with JC Smale setting machines in its Australian plants, so it decided to replace its old setting machines with a new JC Smale unit, capable of setting 30,000 modular brick per hour and 14,000 large face brick per hour—about 54 cars in an 11-hour shift.
The new setting machine also features a push-through cutter that raises a single brick slug up vertically through the wires rather than pushing a double slug horizontally through the wires, resulting in much straighter cuts. The cutter also rolls the edges of the brick slightly to prevent the chipping that is common with architectural brick. In addition to the increased product quality provided by the new machine, a double wire bank design has significantly reduced downtime for replacing broken wires. “If a wire on the old cutters broke, we’d have to stop immediately to change wires. This machine automatically switches from one bank to the next and keeps running,” said Williamson.
For its unloading operation, the company switched from a Mark IV and a Signode monorail to an automatic JC Smale unloading machine. “The new machine lets us grade every face brick on the kiln car,” said Williamson. “A defacer system takes each bung and defaces the brick, turning all the faces up. The brick then goes through a grading and refacing area, which puts paper on the brick and refaces the brick, turning it back to a face-to-face placement.”
In its packaging operation, the company replaced its steel strapping system with Signode HT80 strapping heads and plastic strapping, which creates a better quality package. “The plastic strapping system pulls the strapping tight from both the front and the back, and it doesn’t matter how long the package sits on the yard or what kind of weather it sits in—it doesn’t loosen up,” Williamson said.
Adding up the Benefits
The updates in both the clay prep and manufacturing facilities enabled Plant 3 to handle the required increase in architectural brick production—but they also provided numerous other benefits. The plant was able to switch from two eight-hour shifts running seven days per week to one 12-hour shift seven days per week, cutting back on labor costs. Additionally, many of the plant’s labor-intensive operations were eliminated, significantly reducing the potential for ergonomic injuries and lost-time accidents.The quality of the brick has also increased tremendously. In addition to the more accurate batching, blending, cutting and packaging systems, a belt system hooked up to the setting machine has enabled the company to reduce the amount of B-grade brick that it produces as a result of product changeovers. “When we want to change from one color to another we have to put the new color through the extrusion machine and ‘flush out’ the old color. During that flush out period, we were setting about two cars of B-grade product,” said Williamson. While a market does exist for these products, the company only receives about half of the selling price compared to its typical product lines. With the new belt system, the company transports its B-grade slugs back to the clay prep facility, where they are ground up and reused to make more primary products. “Last year, we made about 1.5 million B-grade bricks. This year, in the same amount of time, we’ve only made about 200,000,” Williamson said—an amount large enough to meet their distributors’ needs but small enough to maximize the plant’s profit.
These updates weren’t cheap, but both Kennamer and Williamson are certain that they’ll pay off over the long term. “It’s a nice plant—it was money well-spent,” Williamson said.