LEHMANN MILLS three roll mills and dispersion equipment

LEHMANN MILLS three roll mills: industrial and laboratory roller units, product scraper knives, precision rolls, and drive components.

LEHMANN MILLS: global manufacturer of three roll and dispersion mills

Established over a century ago in Salem, Ohio, LEHMANN MILLS operates under the Butech Bliss group. The plant has produced over 5,000 industrial roller mills for processing high-viscosity suspensions, printing inks, electronic pastes, and cosmetic formulations.

Century-long American engineering legacy with integrated production shops in Salem
Production of over 5,000 heavy three roll mills and precision dispersion assemblies
Integration into Butech Bliss expanding precision metalworking machining resources
Factory reconditioning and maintenance support for Lehmann and third-party brands

Horizontal and inclined three roll mills of the Model 7312KVH series

Heavy-duty three roll mills by LEHMANN MILLS deliver controlled shear grinding and homogenization for pastes with micrometer gap regulation. The build incorporates wear-resistant water-cooled rolls and a rigid welded bed structure to dampen operational vibration.

Horizontal and inclined roll configurations optimized for viscous paste discharge
Precision screw and hydraulic mechanisms maintaining micrometer nip gap positions
Internal water cooling circuits stabilizing temperatures for heat-sensitive pastes
Rigid low-alloy structural steel frames engineered to absorb mechanical vibrations

Model 8A Bench Top precision laboratory mills and two-roll units

Compact bench-top roller mills by LEHMANN MILLS are engineered for testing laboratories and formulation development. These systems deliver exact scalability of dispersion parameters directly onto full-scale industrial roller machines operating across manufacturing plants.

Compact bench-top configuration of the Model 8A series for research laboratories
Two-roll laboratory variants equipped with electric heating zones for polymer trials
Variable peripheral roll speeds and gear ratios enabling fine dispersion control
Repeatable grinding performance ensuring seamless scaling to production equipment

Product take-off scraper knives, aprons, and guide side shields

Finished product take-off assemblies feature quick-change knife blades machined from tool steel and adjustable guide aprons. Bronze side shields retain high-viscosity slurry within the grinding zone, preventing slurry leaks and lateral edge spillage during processing.

Quick-change scraper blades manufactured from heat-treated alloyed tool steel stock
Adjustable take-off aprons featuring micrometer angle adjustment against roll bodies
Bronze and polymer side shields sealing slurry within the operational roller sector
Reduced fluid friction and prevention of thermal residue formation along blade edges

Roll regrinding, crowning profile calculation, and geometry restoration

The LEHMANN MILLS service center calculates custom roll crowning profiles accounting for operational roll deflection and thermal expansion under heavy loads. Precision cylindrical grinding equipment restores roundness, micro-profiles, and runout to original design limits.

Mathematical calculation of roll crowning profiles matched to working slurry loads
Precision cylindrical grinding of roll surfaces with runout kept within micrometers
Restoration of journal bearing necks for precision sleeve assemblies and fluid seals
Ultrasonic non-destructive inspection of roll shells to confirm material integrity

Heavy drive gear trains, bronze sleeve bearings, and rotary unions

Power transmission systems by LEHMANN MILLS feature spur and helical gears cut to precision tolerances, designed to handle high torque under shock loading. Bronze journal sleeves and dual-flow rotary unions ensure extended operational life during continuous mill operation.

Gear transmissions designed with optimized tooth profiles for smooth tooth engagement
Precision bronze journal sleeve bearings machined with integrated lubrication channels
Dual-flow rotary unions supplying heating or cooling fluids into internal roll bores
Flexible gear couplings connecting drive shafts with primary industrial electric motors

Century-long engineering traditions and LEHMANN MILLS history

Founded in 1834 by engineer Johann Martin Lehmann, the original enterprise established fundamental standards for precision roller machinery designed for grinding and dispersing industrial slurries.

The American division LEHMANN MILLS in Salem, Ohio, advanced these competencies by manufacturing heavy three roll mills, producing over 5,000 industrial machines for chemical, coatings, cosmetic, and electronic sectors.

In September 2021, the company joined the Butech Bliss equipment group, pairing decades of roller engineering experience with heavy industrial metalworking capacity in Ohio.

The Salem complex features CNC cylindrical grinding machines, dynamic balancing pits, and coordinate metrology inspection stations ensuring strict manufacturing tolerances.

Mechanical design and fluid dynamics of 7312KVH three roll mills

The 7312KVH series three roll mills deliver precision grinding for high-viscosity pastes via controlled shear velocity gradients between adjacent roll bodies.

The design supports horizontal and inclined roll orientations, optimizing gravitational slurry delivery and uniform paste discharge across the work area without stagnant zones.

Micrometer screw pairs and hydraulic cylinders maintain consistent nip gap openings under fluctuating operational loads.

A massive welded low-alloy structural steel frame absorbs dynamic harmonics, protecting journal sleeve bearings and gear teeth from mechanical fatigue during continuous production shifts.

Model 8A Bench Top precision laboratory mills and testing equipment

Compact bench-top roller mills of the Model 8A Bench Top line are engineered for research facilities and industrial quality control laboratories.

These units reproduce the fluid dynamic conditions of full-scale production mills, guaranteeing direct scalability of experimental data when transferring formulations into high-volume manufacturing.

For evaluating polymer formulations and thermoplastic compounds, two-roll laboratory variants incorporate independent electric heating elements reaching 250 °C.

The systems feature variable-speed digital drives with smooth RPM and torque regulation, enabling realistic simulation of production loads during trial runs.

Product take-off aprons, scraper blades, and guide side shields

Final take-off of finely ground paste from the apron roll is performed by an adjustable scraper assembly featuring micrometer pressure regulation.

Quick-change blades machined from hardened tool steel guarantee clean paste removal without overheating and eliminate mechanical scratching across precision ground roll surfaces.

End side shields machined from bronze or engineering polymers seat tightly against roll shoulders, forming an enclosed hopper for the input slurry.

The shield profile prevents paste migration through lateral seams and stops particulate matter from penetrating bearing housings during continuous material feeding.

Precision roll regrinding and crowning profile calculation services

During intensive grinding cycles, rolls experience combined mechanical deflection from separation forces and thermal expansion. The LEHMANN MILLS engineering center calculates custom roll crowning profiles to create a microscopic convex surface contour that offsets deflection under working loads.

High-precision cylindrical grinding performed on heavy CNC machines restores roll roundness, surface micro-topography, and radial runout to factory specifications. Controlled surface finish provides uniform metal-to-slurry grip and maintains uniform paste film thickness across the full face length.

Drive train gear pairs, bronze sleeve bearings, and rotary unions

Transmission of substantial torque between rolls rotating at differential speeds is handled by heavy gear sets with modified tooth profiles.

Specialized heat treatment of gear teeth ensures high surface fatigue resistance and low operational noise under high starting torque and variable operating speeds.

Roll journal necks are supported by heavy bronze sleeve bearings featuring labyrinth seals and forced oil lubrication. Cooling water is delivered into internal roll bores through dependable dual-flow rotary unions fitted with wear-resistant carbon sealing rings.

LEHMANN MILLS and model names are trademarks of their respective owners and are used only to identify the equipment for which we source parts. SpareX is not an official dealer, distributor or representative of LEHMANN MILLS and is not affiliated with the trademark owner. Origin, documents and warranty are stated for each item in the quotation.