“The really unique factor about this facility is its ability to recharge materials faster than we can batch them,” says Lode. “We can batch at full production for multiple days on end and finish at the end of day with the plant full of materials, ready for the next day,” he says.
Sam Hild, National’s Operations Manager, says: “With a typical plant you would be able to do 300 yards an hour for three or four hours, but at some point, you run out of material. You have to catch up and replenish your bins. This plant should be able to operate at max capacity for an unlimited amount of time.”
With an aggregate storage system capable of handling over 5-thousand tons of live material it’s easy to see why. "Our on-site aggregate storage system has the capability to house and batch ten different aggregates,” says Lode. “We also have a thousand tons of overhead cementitious storage and ten individual silo capacities. That gives us the ability to switch from a specialty aggregate source to what we would call our daily driver, run of the mill aggregates. We can batch 6-thousand PSI side-by-side with 15, 18, 20-thousand PSI concrete and not miss a beat.”
The system is fed by three independent drive-over grizzlies with each lane dedicated to three different materials. DHE’s Scott Humphrey, designer of the facility, says those grizzlies are a unique component of the plant’s high-capacity material storage. “Each grizzly or each lane has its own conveyor system to replenish the batch plant,” says Humphrey.
“We have approximately 1,500 tons of sand, which are over the tunnels to the east. We have 1,500 tons of three-quarter inch aggregate to the west. In the middle, we have two, 1,000 ton bunkers with four compartments each. In addition, we have another 3,000 tons of dead material storage, 1,500 over each tunnel. If they ever needed to, they could literally push a loader into the tunnel feed system,” he says.
Lode says typical plants only have a single grizzly that takes several minutes to offload per truckload. “Older style plants typically just have one drive over grizzly with a radial stacking conveyor that would either put material on the ground or into the respective bins, but you had to wait and move the radial stacker from one material to the next.”
One of the most impressive aspects of the operation is 16-hundred linear feet of conveyors all condensed into about a 200-foot area. When the massive hot-vulcanized belts are running at full speed, they can move some 750 tons of material per hour.
“The two outside conveyors are always live and they're being fed by two tunnels with individual gates or hoppers,” says Humphrey. “As the material is pulled down, they can actually open up another feed hopper, keeping the material moving through consistently. The ten bunker compartments out back feed eight different materials up in the batch plant, with nine and ten being dedicated to the two live conveyors.”
Keeping all that material reliably moving required some special engineering on the part of DHE. “We worked in harmony with the Dodge Gearbox people to develop a floating mount for the gearbox,” says Humphrey. “That minimizes or suppresses motor movement so we're not having any fatigue or shortening the life cycle of the conveyors. It's very unique in the design.”
The gearbox is also tilted to ensure longevity. “The gear oil that's in the box is in the belly of the case where it needs to be,” says Lode. “That way, you have less movement of the gears on a dry run. When this conveyor starts, it's instantly lubricated with the gear oil as opposed to typically how these boxes have rested on their side.”
Rising 100-feet above street level are two 547-ton cement storage bins. Each of the five compartments drop directly into weigh batchers without the help of powder screws. “That’s another unique aspect to Vernon,” notes Lode. “It’s built vertical so transferring cementitious materials is all gravity fed. It's instantaneous, so we're going to pick up three to four seconds on the compression load cell versus the S-type or the hanging scale which will ultimately speed up our batching.”
The dual alley cement silos feature 5” diameter fill pipes with 4” couplings. That gives operators the ability to offload a full 25-28 ton cement train in just 30 minutes.
Positioned near the entry of the site is a two-story batch office with a commanding view of the overall operation. Here, ordering, dispatching, ticketing and batching is handled with an eye to efficiency. At the heart of the operation are state-of-the-art Jonel Archer Batch Controls for full plant automation.
“The nice thing about having the Jonel controls is the amount of data and information that's available to us in real time,” says Lode. “I can hop on my laptop and see exactly what's happening at this plant on every single load in real time. The other nice feature is we're going to be able to look at this plant and analyze the data that's constantly coming and going through this plant. We'll be able to identify any potential maintenance issues before they become a problem.”
As the first load of concrete gets ready to head out to downtown Los Angeles, the National Ready Mix team is ready to put the “megaplant” through its paces. “I’m excited to see how far we can push it, as far as yards per hour. We’re anticipating close to 400 yards per hour,” says Hild.
“The engineering and the overall design of this facility really is quite a feat and a major accomplishment,” says Lode. “When you're looking at over 1200 feet of conveyor moving 2,225 tons of material per hour through a condensed area, it took a lot of design work and a lot of attention to detail to make that happen.”
To order concrete from the Vernon plant please call: (323) 923-4466. For further information and to request a quote to deliver to your project, please contact your National Ready Mix sales representative or call 626-358-9690 ext. 101.