The benchmark in mixing technology

Twin-shaft batch mixer


Twin-shaft batch mixers (DKX) set the benchmark in mixing technology.

bhs_bauma_DKXS_the benchmark in mixing_EN.mp4

Twin-shaft batch mixers (DKX) set the benchmark in mixing technology.

Twin-shaft mixing technology is suitable for all formulas and offers a wide range of benefits. The mixing procedure has a significant effect on the quality of the mixture produced and the economic efficiency of the production process. Watch the video and learn more about major projects from around the world where the twin-shaft batch mixer (DKX) has proven itself under the most difficult conditions.

Consistently high mixture homogeneity and short mixing cycles

  • Rapid increase in mixture homogeneity through intensive material exchange
  • Uniform consistency and homogeneity in every mixing cycle

Optimum energy efficiency

  • Excellent mixing performance despite low mixer speed
  • Preservation of the grain structure of the formulation’s individual components
  • Low specific energy consumption due to short mixing times, optimized mixing mechanism and efficient drive

Design results in low wear

  • Low wear on mixing tools and mixing trough lining due to low speeds and compact design
  • Significantly less wear and tear than with pan or planetary mixers
  • Optimized design of all parts subject to wear

Efficient production of concrete

  • Excellent liberation of binders in a short time
  • Creates potential for reducing the required amount of binder
  • Uniform and fast distribution of additives and admixtures across the entire volume of the mixture
  • Possibility of small batches as low as 10% of the nominal filling level
  • Safe investment in view of modern concrete formulations
  • Supports hybrid mixing cycles (slow – fast – slow)

Comprehensive modular system

Comprehensive modular system

We offer a broad spectrum of mixer sizes and accessories. The extensive modular system allows our twin-shaft batch mixer to be adapted precisely to your needs.

Product range

With our comprehensive range of twin-shaft batch mixers, we offer the right solution for any requirement, thus making our products a safe investment at all times. Depending on the application, you can choose between the following mixers:

  • DKX: The powerhouse for top operational safety
  • DKXS: The all-rounder
  • DKXN: The economical solution for ready-mixed concrete

In addition, we offer mixers with a wide range of configuration options for mixing units, drives, discharge options etc. to address an even grater range of application scenarios.


Pumped concrete

Ready-mixed concrete

Ready-mixed concrete with input size up to 64 mm


Wet mortar


Precast concrete


Specialty concrete grades

Lean concrete

Heavy concrete > 2.4 t/m³

Coarse-grained mixtures up to 160 mm, depending on machine size

Mixtures for concrete block production

BHS Transmission Safety Technology

BHS Transmission Safety Technology

The drive and gearbox unit, which is suspended on an adjustable torque strut, tracks every movement of the mixing shaft. The innovative, high-performance shaft-mounted gear unit absorbs shocks. Along with that, careful material pairing allows the gearbox to compensate for the load changes that occur each time the mixer is filled.

This significantly extends the service life and massively reduces the load on the gearbox.

BHS transmission safety technology: Maintain your equipment in its original condition long into the future.


Advantage of the three-dimensional mixing concept

In contrast to the circular motion of other mixing systems, the three-dimensional mixing principle of the twin-shaft batch mixer produces a more intensive exchange of material, which leads to shorter mixing times while consuming less energy.

Spiral mixing tools

Spiral mixing tools

  • Mixing tools arranged on each mixing shaft in the shape of an interrupted spiral
  • Two counter-rotating mixing shafts with the mixing tools overlapping in the longitudinal center of the mixer
  • Counter blades positioned at the ends of the shafts
  • Moderate circumferential speed of the mixing blades for gentle processing
  • High-quality hexagonal shaft with high torsional and bending strength
  • Streamlined mixing arms made of special cast steel
  • Helical arrangement of the mixing arms as spiral mixer
  • Easily adjustable mixer blades

Mixing principle

Mixing principle

  • Generation of a circular three-dimensional movement pattern of the entire mixture
  • Intensive material exchange in the turbulent overlap zone of the two mixing circuits
  • Optimal conversion of the energy input into intensive relative movements of the mixture
  • Total volume of material is always included in the mixing process


Gearbox [1]

BHS worm gears boast maximum operational reliability and a long service life, even under extreme loads. The gearboxes are attached to the mixing shafts without rigid connection to the mixing trough. Careful material pairing allows the BHS worm gearbox to compensate for the load changes that occur each time the mixer is filled. 

Electric motor [2]

All of our twin-shaft batch mixers are equipped with high-quality motors. They are specifically designed for the load cycles generated.

V-belt drive [3]

The power is transferred via V-belt drives. Positioning the V-belt drives on the outside of the drive provides good accessibility when performing maintenance work.

Torque support [4]

The adjustable torque support is used for the alignment of the gearboxes. It also allows the gearbox to be fastened to the mixing trough without pressure, avoiding unnecessary loads on the gearbox toothing. This special feature is an essential prerequisite for achieving a long gearbox life.

Synchronous coupling [5]

A low-maintenance elastic coupling is installed between the gearboxes to synchronize the two mixer shafts.

Fluid coupling (optional)  [6]

The hydrodynamic fluid coupling prevents both mechanical and electrical load peaks. Its use is recommended in particular if unstable electricity supply conditions prevail on site.

Shaft seal & bearing

The mixer shafts are reliably sealed with axial face seals. The shaft bearings are mounted on bearing lanterns and are physically separated from the shaft seals. This significantly increases the operational reliability of the mixer shaft bearings.

Special designs

Concrete paving block

Top level of homogeneity for base and top layer

The production of concrete for paving blocks requires highly reliable mixing technology with consistently high levels of homogeneity. The filigree top layer, in particular, requires extremely homogeneous concrete to minimize rejects. The proven twin-shaft batch mixer (type DKX) has been configured by BHS accordingly. The result is a special mixer configuration for concrete blocks with adapted speed, accurate humidity measurement and water dosing, as well as a smooth mixing system and a high-pressure cleaning facility.

Twin-shaft batch mixer (DKX) for the production of concrete paving blocks


Twin-shaft batch mixer (DKX) for the production of concrete paving blocks

Smooth mixing unit, three-dimensional mixing principle and maximum reliability: Efficiency and quality go hand in hand at BHS. The mixer is the key component in the production of concrete paving blocks. Our proven twin-shaft batch mixer can adapt flexibly to your needs and requirements and mix even small batches reliably. Watch the video to learn more about the twin-shaft batch mixer (DKX) in use at the concrete block factory of Excluton.

Sand-lime blocks

Homogeneous and reliable

The production of sand-lime blocks requires highly reliable mixing technology with consistently high levels of homogeneity. The BHS twin-shaft batch mixer (type DKXK) meets these requirements while ensuring fast mixing times and reliable, reproducible results. Colors, too, are distributed quickly among the mixing material without leaving any streaks. Due to its design, the twin-shaft batch mixer of type DKXK is less prone to wear and tear than conventional mixing systems. Its rubber trough makes the DKXK ideally suitable for operation as a main mixer for highly abrasive sand-lime blocks. Twin-shaft batch mixers of the DKXK series are available with capacities ranging from 1,000 to 6,500 liters.

Twin-shaft batch mixer (DKXK) for the production of sand-lime blocks


Twin-shaft batch mixer (DKXK) for the production of sand-lime blocks

Watch the video to learn more about the use of the twin-shaft batch mixer (DKXK) at the sand-lime blocks plant of Hermann Peter KG. The customer Hermann Peter uses the twin-shaft batch mixer DKXK with its rubber trough as the main mixer upstream of the reactor.

Combimix (DKXC)

Our patented Combimix system transforms the BHS twin-shaft batch mixer into a mixer that operates continuously according to the proven twin-shaft technology and allows for adjusting the mixing time. This improves the performance up to 60% compared to batch mixing processes.

Laboratory mixer

Perfect for your concrete laboratory: Our twin-shaft batch mixer in a configuration that produces about 60 l of hardened concrete per batch. The complete mixer is scaled down so that it achieves meaningful test results that are reproducible in the actual production machines.

Vacuum mixer

We can adapt our twin-shaft batch mixers so that a vacuum can be applied during the mixing process. This makes it possible, among other applications, to produce a mixture with particularly low air void contents.

Mixing mechanisms

Universal mixing unit

Universal mixing unit

This features a 60° arm inclination for the production of ready-mixed concrete, precast concrete, special concretes and many other mixing materials.

Smooth mixing tools

Smooth mixing tools

This serves to reduce adhesions to a minimum, even when processing sticky mixtures.

Coarse particle mixing system

Coarse particle mixing system

For the production of concrete used in dam construction, this system is suitable for aggregates up to 180 mm, depending on mixer size.

Twin mixing mechanism

Twin mixing mechanism

For the production of dry and moist mixtures with many fine particles. This doubling of the mixing arms significantly increases the number of relative movements in the mixture, resulting in shorter mixing cycles.

Wear lining

Diamond-shaped tiles

Diamond-shaped tiles

Diamond-shaped tiles with a material thickness of 19 mm made from optimized chrome chilled cast alloy can be used as mixing trough lining. The service life improves by up to 30 % compared to rectangular tiles.



We offer rhombus-shaped tiles with a material thickness of 28 mm for high-wear applications. The variable hardness of the individual tile rows ensures uniform abrasion across all wear zones. This nearly doubles the service life compared to the 19-mm rhombic tiles.


Discharge gate design features

  • Solid and robust cast construction
  • Centrally located between the two mixing shafts
  • Effective sealing due to adjustable gate rails
  • Precise regulation of the discharge volume
  • Reliable actuation using pneumatic or hydraulic cylinders

Standard-sized rotary gate is a fit for most applications

Rotary gate in split design for alternate discharge to two discharge points

Discharge flaps for residue-free emptying – especially suitable for applications in the cement, dry mortar and disposal industries

Lubrication Systems

Central lubrication

The central lubrication system continuously supplies the internal mixing trough seals with grease during mixing operation. Manual lubrication of the seals is only necessary after each mixer cleaning.

Impulse-driven central lubrication

Impulse-driven central lubrication

The impulse-driven central lubrication system supplies the internal axial face seals with grease. After mixer cleaning or when required, lubrication of the seals can be triggered via the control unit at the push of a button. The running time is freely adjustable.

Fully automatic central lubrication

Fully automatic central lubrication

The lubrication points of the four axial face seals, the four internal mixer trough seals (and, as an option, the other lubrication points of the mixer) are automatically supplied with grease via a PLC controller and by means of a progressive distributor. To lubricate the system after mixer cleaning, it is sufficient to trigger the grease pump via the PLC control.

Options & accessories


Moisture and temperature measurement

Moisture and temperature measurement

Our twin-shaft batch mixers can be equipped with measuring probes from all major manufacturers for measuring the moisture or temperature of the mixture. Due to its design and the intensive, three-dimensional movement of the mixed material, the twin-shaft batch mixer provides particularly reliable measuring results.



Our twin-shaft batch mixers can be fitted with a front-mounted device for taking mixture samples. This option represents a decisive advantage, especially when it comes to producing demanding concrete formulations.

Installation in electrical terminal box

Installation in electrical terminal box

If required, all electrical wiring can be bundled in a terminal box for easy installation.

Maintenance platforms and footholds

Maintenance platforms and footholds

To ensure easy access for cleaning and maintenance work, our twin-shaft batch mixers can be supplied with maintenance footholds or movable maintenance platforms.

Machine and plant accessories

Mixing trough cover

The dust-proofed mixing trough cover of our twin-shaft batch mixer is equipped with large maintenance hatches that are opened with the aid of gas springs. A wide range of optional custom connections for feeding, venting, video monitoring or color and fiber addition are available upon request. Dust can be successfully removed via airbags or an active filter.

Water metering

Depending on the requirements, water can be added through baffle plates or water spray pipe systems (non-pressurized or pressurized). The water nozzles of the pressurized water spray pipe system are designed for pure and recycled water. We offer reliable steam injection systems for the production of hot concrete.

High-pressure cleaning

Our proven high-pressure cleaning system with three-dimensional rotating nozzle heads delivers excellent cleaning results and uses water very sparingly. The high-pressure cleaning system can be extended by an additional ring piping system for cleaning the discharge hopper. In twin mixing systems, only one unit is required for cleaning both mixers alternately.

Skip hoist

For applications where fast and clean feeding of the mixer with aggregates is of the essence, we offer tailor-made, robust skip hoists in tipping bucket or bottom discharge design.


Wir bieten für die Mischgutabgabe in den Fahrmischer oder offenen LKW bewährte Standardlösungen als auch individuelle Lösungen an. Abbildung: Entleertrichter in Gummikorbversion mit hydraulisch einschwenkbarem Tropfschutz, zusätzlichem Trichter für Kipperverladung, Reinigungsringleitungssystem, Gewichtsüberwachung und Revisionsrahmen mit Teleskopstützen.

Technical specifications

Performance data
per batch
Maximum compacted concrete outputStandard
drive 3)
Maximum aggregate size
Truck mixer
discharge 1)
Open truck discharge 2)Quality concreteHydro dam concrete 4)

DKX 0.50

0,75 m³0,5 m³73 cycles/h37 m³/h73 cycles/h37 m³/h15 kW64 mm-
DKX 0.751,13 m³0,75 m³65 cycles/h49 m³/h65 cycles/h49 m³/h22 kW64 mm-
DKX 1.001,5 m³1 m³58 cycles/h58 m³/h60 cycles/h60 m³/h37 kW64 mm80 mm
DKX 1.251,88 m³1,25 m³53 cycles/h66 m³/h53 cycles/h66 m³/h45 kW64 mm125 mm
DKX 1.672,51 m³1,67 m³48 cycles/h80 m³/h49 cycles/h82 m³/h55 kW64 mm125 mm
DKX 2.003 m³2 m³49 cycles/h98 m³/h53 cycles/h106 m³/h65 kW64 mm150 mm
DKX 2.253,38 m³2,25 m³46 cycles/h104 m³/h50 cycles/h113 m³/h65 kW64 mm150 mm
DKX 2.503,75 m³2,5 m³48 cycles/h120 m³/h56 cycles/h140 m³/h75 kW64 mm150 mm
DKX 2.754,13 m³2,75 m³46 cycles/h127 m³/h55 cycles/h151 m³/h2 x 45 kW64 mm150 mm
DKX 3.004,5 m³3 m³44 cycles/h132 m³/h53 cycles/h159 m³/h2 x 55 kW64 mm150 mm
DKX 3,335 m³3,33 m³41 cycles/h137 m³/h50 cycles/h167 m³/h2 x 65 kW64 mm150 mm
DKX 3.505,25 m³3,5 m³42 cycles/h147 m³/h52 cycles/h182 m³/h2 x 55 kW64 mm160 mm
DKX 4.006 m³4 m³39 cycles/h156 m³/h49 cycles/h196 m³/h2 x 65 kW64 mm160 mm
DKX 4.506,75 m³4,5 m³37 cycles/h167 m³/h51 cycles/h230 m³/h2 x 75 kW64 mm160 mm
DKX 5.007,5 m³5 m³35 cycles/h175 m³/h50 cycles/h250 m³/h2 x 90 kW64 mm160 mm
DKX 6.009 m³6 m³31 cycles/h186 m³/h48 cycles/h288 m³/h2 x 110 kW64 mm160 mm
DKX 7.0010,5 m³7 m³28 cycles/h196 m³/h44 cycles/h308 m³/h4 x 75 kW64 mm160 mm
DKX 8.0012 m³8 m³26 cycles/h208 m³/h43 cycles/h344 m³/h4 x 90 kW64 mm160 mm
DKX 9.0013,5 m³9 m³24 cycles/h216 m³/h43 cycles/h387 m³/h4 x 110 kW64 mm180 mm

1)  30 s mixing time, truck mixer input rate of 0.12 m³/s (0.16 yd³/s) and compactability rate of 1.15.
2)  30 s mixing time, compactability rate of 1.45.
3)  Alternative drive power available on request for other applications.
4)  For types DKX 1.00 to DKX 4.50 with coarse-grain mixing tools.

Performance data for other materials available on request. All specifications apply to the standard version. Technical data for customized designs may differ from the specified data. All technical data may change due to development. Subject to modification without notice. 

Dimensions and weights 
TypeABCDEFWeight 5)

DKX 0.50

2.310 mm1.275 mm1.655 mm1.550 mm1.470 mm1.000 mm3.100 kg

DKX 0.75

2.540 mm1.500 mm1.880 mm1.550 mm1.470 mm1.000 mm3.600 kg

DKX 1.00

2.400 mm1.230 mm1.570 mm2.040 mm1.830 mm1.200 mm4.040 kg

DKX 1.25

2.590 mm1.500 mm1.840 mm2.040 mm1.885 mm1.200 mm5.200 kg

DKX 1.67

2.920 mm1.765 mm2.105 mm2.040 mm1.940 mm1.200 mm5.700 kg

DKX 2.00

2.590 mm1.480 mm1.900 mm2.470 mm2.040 mm1.400 mm7.500 kg

DKX 2.25

2.850 mm1.740 mm2.160 mm2.470 mm2.040 mm1.400 mm8.100 kg

DKX 2.50

3.100 mm1.990 mm2.410 mm2.470 mm2.070 mm1.400 mm9.000 kg

DKX 2.75

3.150 mm1.990 mm2.410 mm2.470 mm2.080 mm1.400 mm9.600 kg

DKX 3.00

3.410 mm2.250 mm2.670 mm2.470 mm 6)2.080 mm1.400 mm10.200 kg

DKX 3.33

3.410 mm2.250 mm2.670 mm2.470 mm2.110 mm1.400 mm10.400 kg

DKX 3.50

3.250 mm1.995 mm2.400 mm2.855 mm2.320 mm1.650 mm13.400 kg

DKX 4.00

3.500 mm2.255 mm2.660 mm2.855 mm2.320 mm1.650 mm14.000 kg

DKX 4.50

4.270 mm2.510 mm2.915 mm2.855 mm2.400 mm1.650 mm14.700 kg

DKX 5.00

4.260 mm2.410 mm2.870 mm3.180 mm2.760 mm1.950 mm22.000 kg

DKX 6.00

4.790 mm2.940 mm3.400 mm3.180 mm2.800 mm1.950 mm24.000 kg

DKX 7.00

5.290 mm3.475 mm3.935 mm3.180 mm2.590 mm1.950 mm29.000 kg

DKX 8.00

5.440 mm3.475 mm3.935 mm3.180 mm2.800 mm1.950 mm34.000 kg

DKX 9.00

5.980 mm4.010 mm4.470 mm3.180 mm2.800 mm1.950 mm37.000 kg

5)  Weight for standard design without accessories.
6)  2,350 mm for DKX 3.00 in ISO variant.