Safety and simplicity: the weigh forward

Key issues facing machinery manufacturers include cleanability, accuracy, validation, reduction in external services and the ability to work in isolators.

With these factors in mind, Adelphi Manufacturing, has developed the TGM S420 tube filling machine. The orientation device has been moved from above the tube to below it and the essential connections to crimping jaws are totally enclosed in a single stainless gantry.

On their Rota R911 filling machine, the ampoule draw off has been redesigned to allow a steady-flow of air away from the drug surface. Nitrogen purging is now provided not just before and after filling, but during filling and during the flame-heated closing process. After enclosure of the drug product, processes such as crimping of vials, are conducted away from the area where the drug is exposed.

The design of dosing pumps has also been changed radically. Rotary-type stainless steel pumps replace the old-style linear slide volumetric pumps because they have a much smaller number of parts, fewer different materials in contact with the product, are easier to clean and validate and are more accurate.

Ceramics have become the standard production materials for very small doses.

Another development is the use of flowmeters, which are changing the way industries think about liquid filling. Although flowmeters are more expensive than their piston-based counterparts, Brian Potifer, director of filling machine specialists Masterfil said, 'It is a matter of considering the overall cost of ownership.

'Selecting a filler was once a matter of balancing capital cost against speed of output and accuracy. Now, with run lengths becoming shorter, changeover time has assumed much greater importance. Flowmeter fillers provide high up-time and, in our experience, will also reduce maintenance costs.'

Peristaltic pumps are now more popular in some applications because the product is contained in one length of tubing from bulk supply to the filling nozzle.which can be renewed after each batch.

To reduce the problem of damaged or spoilt containers, Swiftpack has designed a system that incorporates a number of innovative features. One of the most common problems associated with filling is damage caused to the containers, either from poorly filling nozzles or by the filling head coming into contact with the containers during the operation.

To overcome these problems, the system uses a positive shut-off valve on each filling nozzle, which prevents stringing or dripping. It also features a new design of nozzle bar lift mechanism within the filling head. In addition, the head is fitted with various sensors, both to control the location of the containers prior to filling and to count containers as they pass under the head.

NJM/CLI introduced a new Model FLX1200 filling machine at Interphex, US recently. The machine is claimed to feature excellent filling accuracy, simple operation and flexibility as well as interchangeable filling systems, which allows the use of volumetric piston filling or electronic flow metering systems. The FLX1200 is built with state-of-the-art electronics and utilises a CTC touch screen operator interface. Programmable filling speeds and nozzle positioning, maintenance-free drive system and quick connections of modular components provide for user friendly operation.

For convenience and accurate filling of a large number of test tubes, Cole-Palmer offers a new Masterflex benchtop robotic dispensing system that fills automatically, quickly and accurately. There is a choice of single or repetitive dispensing, which can fill up to 5,700 test tubes/hr. It is said to be ideal for speeding up processing in small batch pharmaceutical production, or media preparations.

DT King supplies a fully PLC-controlled in-line liquid filling machine. The Technofill Premier liquid filler is multi-headed and is equipped with volumetric gear pumps, which are suitable for dosing a wide range of free flowing products. All control is via touch screen technology with a programmable user-friendly interface.

Packaging Overhaul has launched a new compact liquid filler. The Nu-fill liquid filling machine combines a proven gear pump filling technique with the latest electronic control systems and a fill accuracy of ± 0.5%. The use of a Siemens controlled inverter enables a two-speed fill and three pump sizes, coupled with an extensive range of nozzles, means that volumes from a few millimetres up to several litres can be filled accurately and efficiently.

Minute quantities of pharmaceutical powders can be dosed to a claimed accuracy of 0.5% by the SD-1 microdoser, developed by German manufacturers Optima. Marketed in the UK by Sussex & Berkshire, the auger-based system offers a dosing range of 0.01 to 20g. Operation is either on the timed fill volumetric principle, with feedback compensation for variations in powder bulk density, or as a gravimetric weigher, equipped with a high accuracy load cell.

Dosing augers and the infeed screw from the hopper are servo-motor driven for accuracy and, in common with all other product contact parts, can be quickly disassembled for cleaning without the use of tools.

Another manufacturer using auger based systems is All-Fill International, which was showing two machines at Pakex, the packaging exhibition held in Birmingham, UK recently. The twin head machine comprises a single drive to two independently-controlled augers that ensures minimum dust generation. The Micro-fill unit, a servo-driven ultra-high-accuracy dosing machine fill onto a Mettler precision balance. Volumetric and gravimetric versions of the 10 series filler are available.

As with filling machines, the key to production of these machines is simplicity of use, reducing the footprint and achieving value for money.

Weighing machines

It is widely accepted that a reliable checkweigher is a vital component of any pharmaceutical production line. In a steady growth market dominated by a handful of close competitors, the onus is on checkweigher manufacturers to innovate in order to push demand upward and move the market forward. With accuracy now accepted as given, today's main industry developments are dictated by customer wants and needs.

The European checkweigher market is estimated at around $110 million (€97.2 million) annually.

Companies such as Lock Inspection Systems have been quick to act on these challenges. At the end of last year, after several months of intensive r&d into customer needs, Lock introduced its new WeighChek series of checkweighers to the UK market, combining the requisite accuracy with unparalleled ease-of-use. WeighChek combines user friendliness and enhanced performance.

The machine's display panel is a unique feature; said to be simple to operate, the panel is fully rotatable and tiltable to suit the operators' needs. Its luminescent touch screen is readable even in direct sunlight and delivers critical product information via a series of windows.

A checkweigher's microprocessor is a valuable source of performance and product information, most of which can be printed out on paper. The challenge for checkweigher manufacturers lies in feeding the data into management information systems so users can transmit data via a factory network.

This facility will shortly become a 'must' for machinery manufacturers wishing to remain competitive. Lock has incorporated RS232 and RS485 ports in all of its checkweighers, facilitating integration with the user's existing management information and quality control systems.

Up to 40 WeighChek machines may be networked together, and control and performance data transmitted between each machine and the user's management information system.

Designed to meet FDA standards and built to GMP's, Thermo Ramsey's Icore AC9000 Rx is a checkweigher that can weigh down to a 2g package with an accuracy of ±50mg at speeds of up to 300rpm. The machines also provides real-time statistical process control, reject verification, full graphics and external data communication. Another feature to ensure compliance to GMP's is that product rejects are ejected into a lockable reject bin.