Always strapped for room, wetcast precasters value every square foot of production space. Now production has a new dimension: upwards.
Ratec, a Fort Lauderdale, Fla., equipment manufacturer, unveiled an innovative casting system at bauma. It allows producers to double their productivity in casting high-quality panels without taking up floor space. And with a little ingenuity, producers can also add to their product lines.
Ratec engineers refer to their new pouring technique as die-cast flush-concreting. The system enables producers to inject self-consolidating concrete (SCC) into vertical, high-performance forms. The final product is a high-quality, double-sided, tightly dimensioned element.
The production system has an all-steel, dual-casting chamber. The vertical forms stand 18 feet high atop a sturdy platform. Engineers designed the steel walls and locks to withstand the liquid pressures from SCC. All three walls are mounted on heavy-duty rollers. To open the forms, workers easily open or close the doors.
Depending on the height of the form, a producer can almost triple the production yardage per square foot. Along with increased production, the new forming system is the key tool for a new engineered casting system called Upcrete. Ratec hopes producers adopt the system to economically mass-produce elements for housing.
A key quality facet to the production system is the patent-pending universal concrete inlet. The inlet is a V-shaped, metal apparatus that is designed to attach to any standard pump connection. Following pumping, the valve's closing eliminates any clearance volume. Laborers don't have to carve out any clean-out concrete from the inlet.
The filling crew pumps SCC through the valve's open pipe. The pump's low pressure injects the free-flowing SCC upwards, equally filling both casting chambers. When the concrete reaches the desired height, the laborer keeping pressure on the fresh concrete column closes the inlet's stopper.
Engineers positioned the stopper so it travels at a near perpendicular angle to the form's outlet. They accomplished this by attaching the stopper to a threaded rod that's strong enough to withstand the form head pressure from the fresh concrete. When the laborer wrenches the stopper to its final position, it sits flush with the form's inner wall. The fit is so tight, there is hardly any impression on the cast concrete element.
The new system also eases material handling. The ends-up lift places less stress on the freshly cast element. Producers may be able to reduce ends up reinforcement, which is often added for just the initial pick from a horizontal to vertical position.
That's because after the concrete hardens, it's easier to remove elements with horizontal pours. The demolding crew first secures the element with lifting equipment that is hooked to the crane. Once secured, the laborer rolls one of the outer doors away from the double chamber.
With enough clearance, the overhead crane simply moves the element from its vertical position in the form to the storage area. The second element is removed similarly.
Since the element is cast upward, the only surface that is not provided a manufactured finish is at the top of the element.