William Boulton Ltd. is a British engineering company based in Stoke-on-Trent which was originally founded in 1852. Our speciality is in the design and manufacture of vibratory process plant and machinery.
VIBRO-ENERGY® Ultra Fine Grinding VIBRO-ENERGY® Vibratory Separators VIBRO-ENERGY® Ceramic Polishing & Finishing VIBRO-ENERGY® Industrial Grinding Machines VIBRO-ENERGY® Vibratory Screens VIBRO-ENERGY® Sieving Machines VIBRO-ENERGY® Ball Mill Grinding



Micronizing and Blending


WET PROCESS – For Ultra-fine Grinding, Micronizing and Blending

Ultra Fine Grinding Machine

Only the Boulton design of Vibro-Energy® Mill has the vibratory generator mounted at the centre of gravity of the mill chamber with the coil springs mounted around the periphery of the chamber.

Ultra Fine Grinding Machine for Pharmaceuticals use

This design produces maximum ultra fine grinding efficiency compared to our old, low amplitude, original design with the vibratory generator and springs mounted below the chamber, although this design is still used as it is best suited for our polishing and blending mills where a more gentle action is required.

Boulton Vibro-Energy® Mills offer versatile, low cost, controlled particle size reduction with minimal wear and product contamination. No other type of mill has so few mechanical moving parts. Power consumption is low as there are no rotating impellors or drums.

The mills utilize inert high density sintered ceramic or carbide grinding media for iron-free grinding. The media is cylindrical or ball shape and is subjected to a high frequency, high amplitude vibration producing a vibrating and tumbling vortex action within the annular shaped grinding chamber. The process material fills the void spaces within the media mass.

Pharmaceuticals Use Machines by Williamboulton
Blending Machine for Pharmaceuticals use
Ultrafine Grinding Machine Manufacture

Dry batch or continuous mills are available for specialised applications

In conjunction with cylindrical shaped grinding media the close packed mass preferentially reduces larger particles due to the media line and plane contact surfaces, producing milled materials with a narrow particle size band distribution. All mills are adjustable for low amplitude operation if required.

Mill contact parts are either cast polyurethane at hardness 85-90 Shore “A”, polyethylene, vulcanised rubber or steel.

All mills are primarily designed for wet fine grinding in the particle size range 5 mm to sub-micron, either batch, continuous – open or closed circuit operation.

Call Today On:01782 816 158


For dry grinding and mixing/blending of pharmaceutical powders

The grinding chamber is manufactured entirely in stainless steel AISI 316L, continuously welded and stress relieved.

The mill utilises high density alumina, zirconia or zirconium silicate sintered ceramic grinding media.

The powder process material fills the void spaces within the media mass which is subjected to a high frequency, high amplitude vibratory/gyratory action producing a vibrating and tumbling vortex motion within the annular shaped grinding chamber.

Operating frequency is 16 – 19 cycles per second. Maximum amplitude of vibration is 9 mm. Internal surfaces of the chamber are crevice-free, lined with FDA approved hard polyurethane. The mill is suitable for vacuum or pressurised operation, incorporating gas or liquid purge facility. Tri-clamp fittings and silicone rubber seals are standard.

Data acquisition instrumentation such as amplitude of vibration transducers, temperature and humidity are also available.

The mill is designed for batch operation and is available in a range of powder capacities from 1 litre laboratory size to production sizes up to 200 litres.

Call Today On:01782 816 158

VIBRO-ENERGY® Micronizing and Blending

DRY PROCESS Micronizing and Blending

Vibro-Energy Mixers/Blenders operate at a more gentle, higher frequency than the grinding mills, producing a fast vibrating and tumbling vortex action within the annular shaped chamber for the mixing and blending of dry materials.

As there are no rotating parts within the mixing chamber, the machine is completely safe in operation, is easy to clean, has no rotary shaft seals and offers a lower cost alternative to traditional screw, paddle, blade and ribbon type mixers. Sizes range from 25 litres to maximum 1100 litres working capacity.

The charge of process materials is subjected to a high frequency vibratory spiral/tumbling action at 24 – 29 cycles per second. Grinding media can be added to reduce agglomerates. Media can be sintered ceramic, steel or carbides, as cylinders or spheres. The mills can be operated without media, for dry mixing and blending only.

  • Inherently safe in operation
  • No guarding required
  • No ferrous contamination
  • Minimum space requirements
  • Easy to install
  • Low power consumption