Wetcast production plant Slab-Flex delivered to South Korea

Just recently, Afinitas delivered a new wetcast production plant to the South Korean manufacturer Finnocon to produce concrete blocks in elastic formwork shapes on wooden or steel pallets in multiple production.

The basic equipment of the machine is designed for one product size per pallet. In order to be able to produce different products with this equipment, additional elements have been offered, which can be easily exchanged. With these elements several product sizes can be positioned and produced on one pallet. The machine is equipped with the following units:

1 Conveyor and hydraulic power unit

1.1 Timed conveyor

The time-controlled conveyor transports the pallets through the entire production line including the infeed and outfeed buffer station, consisting of a transport frame that is guided by guide shoes with linear movements and transports the pallets to the next station. By means of hydraulic cylinders, the pallets are gripped by engaging latches that ensure exact positioning in the respective production station.

The conveyor has a cycle time of approximately 30 seconds, with a slower movement selected when a stack of molds is moved in and out to ensure that these stacks are moved in and out safely. The movement is controlled by a proportional hydraulic solenoid valve, which ensures uniform acceleration and deceleration of the pallets.

1.2 Central hydraulic power unit

A central hydraulic power unit is provided for the transport, respectively for the stacking and destacking magazines and the vibrating table; in addition, the hydraulic power unit is extended for the additional options offered.

2 Unstacking and stacking of pallets (2 pcs.)

The pallet/form is positioned in the destacker of the indexing conveyor with a forklift. One pallet is left on the indexing conveyor and the remaining stack of molds is lifted. After the mold is transported by the indexing conveyor, the complete stack is lowered onto the indexing conveyor and again the plate stack is lifted without the plate at the bottom; the operation is hydraulic. Mold stacking is performed in the reverse direction, the stacking system is designed for max. 15 pallets, including share of control elements and hydraulic cylinders. Optionally, an extension for stacking and destacking magazine enables stacking of two different pallet heights.

3 Demolding roller unit and demolding station

3.1 Demolding roller unit

The demolding roller unit is designed to open the upper mold frame to support the demolding process and is in front of the demolding station.

3.2 Demolding station

The concrete elements are simultaneously gripped by a vacuum suction unit via a linearly adjustable vacuum lifting frame. They are lifted out of the mold and deposited on a roller conveyor next to the indexing conveyor. During stripping, the molds are held down on the plank by a hold-down device and the side mold walls are opened so that the concrete products can be removed. The hold-down device is interchangeable to allow quick changeover to pallets with other products. The hold-down device consists of the holder and a hold-down frame. The hold-down device was included in the price, but not the holding frames for the individual products; the pick-up device as well as the vacuum cup are included, but not the suction cups, including control part and pneumatic or hydraulic cylinders.

An extension of the demolding station: allows demolding of heavy products, but only in semi-automatic mode. The mold must be manually removed and reinserted into the line.

4 Hold-down frame and vacuum suction cup

4.1 Holding-down frame

This item includes three holding-down frames for quick pallet change with one or two molds, one holding-down frame for quick pallet change with three or four molds, and one holding-down frame for quick pallet change with up to six molds.

4.2 Vacuum suction cup

Furthermore, the scope of supply included 6 pcs vacuum suction bell for various products with fixing device.

5 Product turning device and conveyor

5.1 Product turning device without 90° change of direction

The product turning device (without 90° change of direction) is designed for immediate turning of fresh products from the front side to the back side, consisting of a transport unit on which the panels are placed by the demolding unit (approx. 1.2 m long), a turning device with change of direction incl. control share and pneumatic-hydraulic cylinder. In addition, there is an extension for tipping device in such a way that higher products can be transported, but without turning.

5.2 Conveyor, with drive

A conveyor with drive (coming from the turning device, approx. 5 m long) provides for the transport of the products.

6 Vacuum tube lifter, cleaning and oiling station

6.1 Vacuum tube lifter (optional)

A packing aid in the form of a vacuum tube lifter, lifting capacity approx. 130 kg, is optionally available for packing the plates.

6.2 Cleaning station for molds

A mold cleaning station by means of a dumping device for the entire production plate with molds, including a pneumatic extension for the cleaning station with four pneumatic cylinders has the task of keeping the molds in position during dumping. Also included is an electric control unit, but not the waste container (exclusive).

6.3 Oiling station

One oiling station for spraying release agent into the concrete contact area of the molds, for easy demolding of the finished concrete products from the PUR molds.

The spraying device is designed as a suspension bridge above the cycle belt; the three gun nozzles are adjustable in quantity and direction. The spraying unit operates without air, equipped with a collecting tray for the demolding agent and with an enclosure, including an electrical control component.

7 Concrete batching unit and batcher

7.1 Concrete batching unit type ATL

Afinitas also supplied a type ATL concrete feeding unit with a single hopper, with a capacity of approx. 750 l (removable for cleaning) and a concrete screw conveyor.

The feeding unit is mounted on a hanging gantry above the indexing belt as well as above the leveling table. Three continuously adjustable metering chambers for filling the concrete are attached to the hopper of the hopper. These metering chambers consist of a rectangular container that is actuated by means of a hydraulic cylinder. The dosing chambers correspond to the volume of the molds to be filled.

Below the metering chambers there is a discharge opening through which the green concrete is filled into the prepared mold frame. When changing the molds, the delivery volume can be easily changed automatically, including cylinder and control part for the automatic function.

The main batcher includes a concrete hopper (750/750 l), with a second concrete auger, for placing a second concrete color.

7.2 Height-adjustable charging unit (optional extension)

As an optional extension, the feeding height of the unit can be adjusted hydraulically, with a maintenance bridge in front of the batching unit.

7.3 Special leveling device

A special leveling device is positioned under the batcher, including base frame, for leveling the concrete.

8 Special vibrating table

Both vibrating tables are mounted on separate frames with vibration isolators. During the compaction process, the mold is fixed to the vibrating table by clamping devices. The vertical vibrations are transmitted to the molds by two high-frequency electric vibrators with approx. 11 kN each.

The delivery includes a base frame, two vibrators with control elements, and a frequency converter for setting the vibrators via a potentiometer on the control panel.

9 Main control, safety and documentation

9.1 Main control system

The main control system for operating the wet and dry line is a Siemens make, with power sections integrated in control panels, including panels with all electronic elements for manual/automatic operation.

9.2 Safety, documentation and instruction

The delivery package to the Afinitas customer is rounded off by safety equipment such as light barriers, fences and safety gates depending on local conditions, overall documentation and instruction for the entire plant, and modem for remote access to the machine via the Internet.