The German market for vertical single-shaft mixers in powder and bulk solids technology is characterised by a number of specialised, predominantly medium-sized mechanical engineering companies which are regarded as "hidden champions" and are active worldwide. These manufacturers develop and produce vertical mixing systems for demanding applications in the chemical, food and pharmaceutical industries, in building materials and dry mortar production as well as in plastics and ceramics processing.

Leading suppliers typically distinguish themselves through the following characteristics.

High depth of manufacture and their own pilot plant

Their own trial facilities (pilot plants) for customer-specific mixing trials with original products, including determination of mixing quality, homogeneity (CV) and batch times.

Process engineering expertise

Design of the mixers on the basis of bulk density, particle size distribution, flow behaviour, moisture content, abrasiveness and, where applicable, explosion protection requirements.

Customer-specific construction

Adaptation of vessel geometry, mixing tool (for example helical ribbon or helix, paddle), drive power and speed range to the respective mixing task, including options for liquid input, granulation or coating.

Scalability

A portfolio from laboratory and pilot-plant units through to large mixers with several cubic metres of usable volume, frequently also available as combined mixing and drying apparatus.

Hygienic design and cleanability

Dead-space-free, smoothly executed and often electropolished product-contact surfaces, joint-free weld seams, large inspection doors and standardised CIP/WIP concepts for applications in accordance with GMP, FDA and EHEDG guidelines.

ATEX and standards conformity

Designs in accordance with relevant standards and directives (for example ATEX for combustible dusts, CE, ISO 9001), in particular for chemical and food applications.

After-sales service and retrofit

Long-term spare parts supply, maintenance offerings, modernisation of existing plants and integration into process control systems via common industry standards.

Since many of these companies are described in a brand-neutral way in trade publications and their market position depends on reference projects, a specific search for suppliers is best conducted via:

• Trade fairs such as POWTECH / SOLIDS, at which a broad spectrum of manufacturers of vertical and conical mixers is represented.
• Industry associations, in particular the VDMA trade association for process plant and equipment, with manufacturer overviews for mixing technology.
• Specialised bulk solids and process engineering portals and engineering consultancies which support manufacturer-independent selection and design.

Typical leading manufacturers offer vertical single-shaft mixers which:

• enable high mixing qualities with dry, moist and suspended powders,
• achieve a very good discharge rate, a small footprint and high fill level flexibility (often 10–100 % of the usable volume) through the vertical design,
• can be operated as contact dryers or reactors under vacuum with optional double jackets and heated shafts,
• are equipped where required with cutting rotors (choppers) for deagglomeration and for the fine incorporation of liquid components.

For users it is practical not to tie the question of "leading manufacturers" to the familiarity of a brand name alone, but to:

• demonstrable references in comparable processes,
• available trial facilities,
• documented hygienic, GMP and ATEX concepts,
• the ability to integrate into their own automation environment and
• the quality of service and support across the entire life cycle of the plant.