Screed mixer-pump S8 CM

Product overview
The S8 CM is a continuous mixing and pumping unit for lightweight screeds and cement- or anhydrite-based self-levelling screeds. Designed and built by BUNKER, the machine integrates a continuous spiral metering mixer, foam generator and a screw pump to enable a continuous work cycle and a consistent homogeneous mixture without the interruptions of separate mixing and pumping operations.

How the machine works
The cement powder (bags or silo) is fed into the hopper of the continuous mixer. In the mixing chamber the following are introduced simultaneously:

• The cement powder, via the spiral metering unit in the mixer hopper
• Water, dosed by the electric water pump mounted on the machine
• Foam, produced and dosed by the integrated foam generator

The materials are rapidly mixed to the required consistency and density. The mixture discharges into the mixing/pumping hopper where it is further blended and then pumped by the screw pump through rubber hoses to the installation point. The system guarantees continuous mixing and pumping with a stable homogeneous mix over time.

Benefits

• Elimination of segregation
• Consistent, controlled consistency and density
• Absence of lumps
• Pumping process free of recurring blockages

Poly B (optional accessory)
The Poly-B is a pneumatic conveyor for polystyrene beads, driven by a three-phase electric motor – 2.2 kW 400 V 50 Hz. It comprises a hopper, compressor and venturi tube that injects polystyrene beads into the mixing chamber of the S8 CM. By adjusting compressed air flow it is possible to vary screed density and thermal conductivity. Combined with the S8 CM it enables a continuous work cycle; with one operator the production can reach about 10 m³/h (mixture: water, cement, polystyrene beads Ø 3 mm, foam density 300 kg/m³). Typical uses: thermal insulation of substrates, roofs and terraces. Geotechnical uses: cavity filling, historic building renovation, anti‑vibration foundations, prefabricated elements, foundations on marshy ground, masonry blocks and attics.

Applications

• Lightweight screeds for thermal insulation floors
• Anhydrite and cement-based self-levelling screeds
• Cellular concrete with polystyrene beads

Accessories & key features

• Transfer cap for silo feeding (SILO compatible)
• Continuous mixer with spiral metering
• Mixing/pumping hopper with special mixing blade coupled to screw pump (double mixing)
• Foam generator and pump for foam dosing
• Water pump for dosing water
• Additive dispenser (Dosatron shown on page)
• Control panel for operations
• Water / foam regulation handles
• Level probe for hopper monitoring

Technical specifications

• Electric motor screw pump: 5.5 kW 400 V 50 Hz
• Electric compressor: 1.5 kW 400 V 50 Hz
• Air output: 250 l/min
• Water pump: 0.75 kW 400 V 50 Hz
• Pump (foam generator): 0.75 kW 400 V 50 Hz
• Continuous mixing motor: 3 kW 400 V 50 Hz
• Hopper capacity (continuous mixing): 60 l
• Hopper capacity (mixing and pumping): 120 l
• Loading height continuous mixer: 1020 mm
• * Weight (machine without mixer shaft): 500 kg
• Total installed power: 11.5 kW
• Adjustable axle: work position – road use position
• Recommended generator: 40 kVA - 32 kW 400/230 V, 50 Hz – 1500 rpm soundproof
• Cellular concrete (with polystyrene): Horizontal conveying distance **: 180 m; Vertical conveying distance **: 60 m; Maximum theoretical pressure: 15 bar; Theoretical screw pump output: 135 l/min; Maximum grain size: 9 mm
• Self-levelling screed (anhydrite and cement based): Horizontal conveying distance **: 120 m; Vertical conveying distance **: 40 m; Maximum theoretical pressure: 30 bar; Theoretical screw pump output: 80 l/min; Maximum grain size: 10 mm
• ** Conveying distances depend on material, consistency and hose diameter