• With a mobile block and paver plant, producers cut costs by delivering production instead of products to the jobsite.

    Credit: Reid Fleming Industrial

    With a mobile block and paver plant, producers cut costs by delivering production instead of products to the jobsite.
  • The self-contained mobile plant includes a mixer, conveyor, block machine, pallet feeder, and stacker. A cement silo, generator, and aggregate bins complete the setup.

    Credit: Reid Fleming Industrial

    The self-contained mobile plant includes a mixer, conveyor, block machine, pallet feeder, and stacker. A cement silo, generator, and aggregate bins complete the setup.

Unlike their perishable ready-mixed cousin, concrete block and pavers aren’t constrained to projects within a strict delivery radius. Producers of concrete products often find themselves bidding on jobs in a different state, or even across the country. However, this wide-open market brings its own challenges.

While a producer may have the right product at the right price for a distant project, profit margins can be quickly dissolved by high delivery costs. “A lot of work is going on right now outside of the efficient transportation range of production plants, and fuel costs are high,” says Steve Levy, owner of Reid Fleming Industrial. “Producers and contractors can’t pass these costs along to customers, and their profits are suffering.”

Taking a cue from the ready-mix industry’s portable batch plants, Reid Fleming has designed a mobile block plant that can be assembled at a jobsite to produce mortarless block, pavers, and segmental retaining wall block. The self-contained plant uses full-size, heavy-duty production equipment that can produce 1000 CMUs or 1600 square feet of pavers per hour.

The trailer-mounted plant includes a 50-cubic-foot mixer and conveyor to the casting machine, and an exit system with a pallet feeder and stacker. The manufacturer’s automated plant package also comes with a 20-ton portable cement silo, 100kva generator, and 2000 production pallets. Separate truck-mounted “dry side” equipment is available for depalletizing and cubing the finished products.

Producers can use Reid Fleming molds or their own to make products ranging from 1-inch pavers to 10-inch retaining wall block with cores — as long as they can fit within the plant’s 36-by-36-inch working surface. The mobile plant is designed with as many commercially available parts as possible, so producers aren’t tied to the manufacturer if replacements are needed.

The manufacturer offers setup and startup support, including training on how to use the equipment in a producer’s specific location. “We meet with customers to go over every nook and cranny of what they want to do, so the system can be up and running smoothly on day-one,” says Levy. Reid Fleming uses program logic controls to monitor the machine while it’s running, troubleshoot, and make any necessary software changes remotely.

Standard operating procedures

Instead of delivering truckloads of block or pavers, producers transport the 30-ton mobile plant to the jobsite. The 40-foot trailer meets highway transport regulations, so no special oversize permits or escorts are required.

Plant setup takes about two days. No foundation slab is needed, but the manufacturer recommends using railroad ties or timbers to support the trailer and absorb vibration during operation. The plant can tap into public power and water utilities, or run on a generator and use water trucked in by a tanker.

In a typical jobsite operation, the producer or self-performing contractor uses a front-end loader to feed sand and aggregates (up to 6-mm crushed limestone) into the plant’s mixer. Cement is fed into the mixer directly from the portable silo. After about four minutes of mixing, the concrete is discharged onto a belted conveyor. It is delivered into the feed hopper on top of the block-making machine, which can be controlled manually or automatically by a solid state programmer.

After the block is formed, the auto stacker lifts the production pallets from the conveyor two at a time, and stacks them onto a single forklift truck pallet. When the stack is 18 pallets high, the producer moves the cube by forklift to a designated spot for drying. The mobile plant uses a very dry mix, vibration, and compaction to produce high-strength block that can be handled within 24 hours; no curing is needed.

New opportunities

Although the movable plant equipment is engineered to be lighter than fixed production equipment, Levy stresses it’s not a light-duty version. In fact, several producers have opted to remove the plant from its trailer and permanently mount it for much less than the cost of a new fixed plant.

One Florida producer uses the equipment as a full-time auxiliary production line when its plant is running at full capacity, or for small or non-standard orders. The plant manager can designate the mobile unit for special block without disrupting production in the main plant.

The self-contained unit can also extend producers’ delivery territory to remote areas where land use rights or lack of infrastructure, such water or power sources, limit opportunities for building new plants. As long as producers have access to raw materials and a generator, they can supply block and pavers to even the most remote jobsite. TCP

Visit www.fleming-mfg.com or telephone 573-265-3314 for more information.