Linotech: Industrial Rotary Press

Linotech, a manufacturer of industrial tablet presses based in France, is part of the Eurotab group. Eurotab is a leading manufacturer and distributor of tablets for the European consumer and industrial markets. Eurotab’s innovations and more than 45 years of experience in manufacturing tablets is reflected in the Linotech line of industrial rotary tablet presses.

Products pressed on Linotech tablet presses include, but are not limited to, dishwashing detergent tablets, laundry detergent tablets, water softener tablets, Chlorine tablets for swimming pools, cosmetics and food products.

Linotech presses are custom-designed to client’s specifications, and are capable of pressing tablets ranging in size from 20 mm to 100 mm in diameter, with the largest press capable of applying a compression force of up to 600-650 kN. It is also possible to press multi-layer up to 5 five layers, cored and tablets-within-tablets.

During manufacturing of the presses, the massive main structures are stabilized by a heat treating process so the presses are able to withstand the tremendous loads encountered when pressing very large tablets. Surfaces are made of stainless steel or coated with application-specific corrosion resistant coatings. The enclosures are safety interlocked with a smooth fit and finish for product containment. The compression chamber can be kept under negative air pressure to reduce operator exposure to dust.

The turrets have hard chrome plating on the working surfaces. Punch holders ride in lubricated bushings. The turrets are driven by powerful AC motors coupled to frequency inverters. The turret drives have enough torque so that the presses can be restarted under full load without any problem. The double paddle powder feeders are driven by variable speed asynchronous servomotors. We can offer many solutions to overcome problems with poorly flowing powders.

Linotech industrial rotary tablet presses are designed to use as many readily available, off-the-shelf components as possible. During maintenance, the modular design makes it easy for technicians to remove sub-assemblies without having to disassemble the entire press. Special tools and removable platforms for the larger presses are available to facilitate maintenance and de-tooling.

Controls:

The control systems automatically monitors pre-compression force to control tablet weight, while the main compression force is monitored by a PID loop to adjust tablet height on order to maintain consistent tablet densities. Independent systems constantly monitor compression forces to retract rollers and shut down press case of over pressure. Other safety systems are also built-into the press prevent personal injury to the operator and damage to the press.

Controls are customized to each customer’s requirements, and employ Siemens PLCs with 12 inch touch screen HMIs with different access levels for operators and supervisors. For tight budgets, some models can be supplied with simplified manual controls (i.e., equipped adjustment hand wheels) .

New Control System Options:

• Unmanned for 24 hour production (when coupled with the Automatic Sampling System described below.)
• Traceability and recording of critical process parameters, identification of parameters deviating from normal and flagging of transient and continuous faults.
• Batch production reports with statistics.
• Recording of short term compression events with real-time processor; graphing of compression profiles.
• Force monitoring and control of individual punches.
• Presses can be interfaced to an Automatic Sampling System to periodically divert sample tablets from the press into an instrument to automatically measures the hardness, weight and height of tablets. The measurement data are fed back to the PLC so that correct tableting parameters are maintained without operator intervention.
• A portable hardness testing instrument and floor standing Height/Weight/Hardness testing instrument for measuring extra large (up to 100 mm) tablets.
• Integration with plant’s MES and MRP systems.