It is often necessary to study tablets made from pure compounds or unlubricated formulations that would normally fracture during ejection. Tablets may fail because of stress created during ejection — friction or shear at the die exit. A common solution is to release the die wall pressure after compaction but before ejection.

The Manual Split Die Holder is an economical method of releasing die wall stresses after compaction and producing compacts for further testing. It fits in the same space as the standard die holder. Dies may be split into two, three or five sections as required.

Compacting a tablet creates very large radial forces on the die wall. When the punch load is released, residual radial die wall pressure often causes the tablet to fracture or develop stress cracks — particularly as the lower punch pushes it out. At the top of the die, the tablet experiences severe shear stresses as the top exits the die first.

To study the compaction properties of pure APIs and other materials that won’t tablet conventionally, a hydraulically actuated split die can release die wall pressure automatically before ejection. Optionally, die wall pressure can be servo-controlled to release in proportion to the axial punch pressure — effectively a tri-axial pressure release.

Die type: Round B or D

Hiestand testing of compressed powders requires a homogenous cubic tablet free of stress cracks. Larger compacts are ideal, but small sizes are also used for material-sparing work. To produce compacts free of stress cracks, tri-axial decompression is required.

The Hiestand fixture, combined with the tri-axial control option, enables Hiestand compacts to be produced on the Huxley Bertram Compaction Simulator. With the High Force actuator option, larger compacts can also be produced. The lower punch holds a retractable probe, allowing compacts to be made with or without a central through-hole.

Moving die faces: 4 individual | Compact size: 10–19 mm | Confining force: up to 85 kN | Axial force: 50 kN or 130 kN options

Cored tablets, or “dry encapsulated” tablets, allow a variety of dosage options and are becoming increasingly common. The core feeder mounts on an existing hopper drive, and additional guides ensure the core is accurately placed. Optional extra hopper drives can be retrofitted. Programming is straightforward and similar to a 3-layer tablet.

Core-rod tooling supports a number of advanced tablet designs — from simple rings, through encapsulated segments, to complex dissolution profiles. Both upper and lower punches can be configured with individually actuated sleeves and core sections to achieve sophisticated tablet geometries.

Compaction simulation is most valuable when there are many production variables to study. The reduced time-to-market and reduced risk of production issues easily justify developing complex dose forms on a sophisticated simulator — cost justification is often achieved on a single project. The Huxley Bertram simulator’s configurable workspace, powerful controller and configurable software make installation of special tooling straightforward.

Available on: HB50 and HB100

Most simulator users produce slugs for granulation as part of their workflow, and many also study formulation behaviour under roller compaction conditions as a material-sparing alternative to running a dedicated roller compactor. Appropriate tooling and software make this work substantially more convenient.

Tooling: Large rectangular punches, typically 22 × 10 mm in D or F format | Software: Automatically loaded roller compaction test profiles

Productivity in a development laboratory is often a critical factor in time-to-market. The standard cost overhead for senior scientists is not a true measure of the cost of their time spent measuring tablets manually and recording the data.

Automatic weight and thickness measurement on the machine frees up valuable time and ensures that more data is correctly and securely recorded. It is especially valuable when tablets contain active pharmaceuticals requiring special handling.

Available on: HB100 and above

Capsule filling development and study is a regular requirement in early-stage drug development. It’s faster and more economical when performed using small quantities of powder on a fully programmable, versatile machine, with comprehensive data recording for future reference.

Easy change-over between tamping disc and dosator pin methods allows both techniques to be evaluated. Automated capsule closure enables convenient production of small test quantities.

Available on: HB50 and above | Methods: Dosator Pin, Tamping Disc

Huxley Bertram normally provides an annual calibration service if requested, often combined with a service visit. Customers who prefer to perform their own calibration, or to use a third party, can be supplied with a calibration kit containing the appropriate devices for the configuration of their machine.

Many powders are dangerous to humans for a variety of reasons, and many new products have unknown levels of toxicity at the development stage. The HB100 Contained variant integrates powder feeding, compaction and tablet handling within a sealed envelope to OEB 5, supporting safe development work with potent compounds.