Spool production goes aseptic

Since the production of its first spool back in 1952, Hafner has managed to accumulate some 54 injection moulding machines, which it now operates in three shifts. Now a leading European manufacturer of spools, the company supplies around 1,400 spool types in diameters ranging from 40 to 1,000mm for a wide variety of applications and in a wide range of materials, including PS, ABS, PE, PP and PA.

It took Hafner just nine months to set up its new cleanroom module for special medical applications. Certificated in accordance with cleanroom Class 8 (ISO 14644), it is free of particles and micro-organisms in line with current Good Manu-facturing Practice (cGMP) Class D.

An injection-moulding machine with a locking force of 3,500 kN forms the core of the new production module. The layout of the facility was designed around the KM 350-2700 C2 injection moulding machine, but only the clamping unit and the mould parts of this machine are housed in the cleanroom itself.

The dust-free material metering and feed systems, the machine’s plasticising unit and the temperature control systems remain outside the cleanroom area in an area called the “grey” room (see figures 1 & 2).

Spools weighing approximately 500g made from impact-resistant ABS are among the first products to be manufactured in the new facility.

The injection moulding of the spool bodies is fully automatic and is carried out in the cleanroom. A five-axis robot, from Reis Robotics, then withdraws the parts from the mould and stacks and packs them in a double-film packaging material as specified by the customer (see figures 6 & 7 opposite).

The spools are packed in the film bags so that they can be transported easily without stress or distortion in an aseptic pack. A single operator sees to the supply of new packaging tubes and the removal of the finished packaged units.

The spools manufactured and packaged in this protective atmosphere arrive, free of micro-organisms and particles, at the premises of the customer, B. Braun Melsungen AG, where they can then be used without any additional finishing costs within its cleanroom facilities. For example, some of the spools are used for winding capillaries and flexible tubes of 0.7 to 5.0mm diameter, for application in permanent venous catheters (Figure 3).

Cost benefit

The operation of a cleanroom area was a new field for the company, as general manager, Jan Hafner, explains: “We first of all considered in great detail what the prospects were, and what outlay in terms of personnel, planning and investment would be needed. In fact, with regard to the actual process of cleanroom production, we had to start from zero since the method of working was completely different. But it soon became obvious that there is great potential for marketing our spools.

“In the final analysis, the delivery of aseptic spools means the customer does not have to bear the costs of a subsequent cleaning step. On the other hand, the costs of installation [of a cleanroom], staff training and certification are distinctly high. It takes a certain learning curve, especially for staff.”

The facility set-up was devised in such a way that there is no need for human contact with the product during production. As a direct consequence, the floor area of the actual cleanroom could be kept extremely small. This means low costs for installation, operation and the routine cleaning and disinfection required by cGMP.

An additional result is that any risk of contamination is reduced to the minimum.

Particular attention was paid to the mould technology employed: well established cooling technology and precise mould temperature control guarantee significant cooling of the relatively thick-walled parts on removal and before the robot stacks them in the film bags.

Both throughput monitoring and water filtration in the temperature control system at this point ensure high process reliability. This reduces the requirement for the machine setter to don special clothing and enter the cleanroom in the event of a fault or in order to change parameters – keeping both costs and contamination risks down. The operator can carry out all essential control operations from outside the cleanroom (figure. 2). Only maintenance tasks or a change of mould require additional access by personnel into the cleanroom.

The company says the unusually fast production start-up time was down to the help of experienced contractors, such as Dittel Cleanroom Engineering. This company, based in Kochel am See, was responsible for the design, planning and certification as well as for assistance in bringing the system into operation.

Hafner says: “We decided to use an experienced associate in order to avoid costly errors even at the planning stage.”

Great value was also placed on the suppliers’ level of experience with cleanroom applications when selecting system and process components.

The cleanroom itself, was constructed by Lindner AG, of Arnsdorf, Germany. This company, from Lower Bavaria, has extensive experience from comparable projects.

The commissioning took place early in 2008, with the handover testing being conducted by Ingenieurburo BSR. Measured values such as particle counts and cleanliness tests produced for the room at this point were superior to the standards required.

Rapid validation

The facility was not only built but also validated in a relatively short space of time. Understanding the machines was key to the project so that, on the one hand, the system would meet government agency requirements, while on the other, its transparency and structure could also confer production advantages and cost savings on the operator.

The validation process required:

• certification of cleanrooms and ventilation systems
• certification of room monitoring systems
• certification of pharmaceutical production plants
• certification of industrial plants and machines
• certification of laboratory instruments
• certification of medical instruments
• certification of computerised systems
• certification of control systems and process control systems
• certification of software systems and software products.

Despite this long list, the project was completed relatively quickly. “Luckily, we made very precise preparations with our associates, even in what appears to be a very short space of time,” says Hafner. “On the other hand, in the fields of mould design and mould making, we have quite a lot of experience that we had to adapt to the requirements of the cleanroom.

“With regard to certification, in accordance with ISO 9001 and 14001 we were able to call upon our 12 years of experience with our quality management system. This system had to be supplemented by the processes required by cGMP – a cost that should not be underestimated.

“In parallel with the launch of the project, staff had to be prepared for this new method of production. High motivation on the part of our staff and extensive training sessions paved the way to success.”

The new installation enables the company to present a more customer-focused service from product development through mould design right up to the production of aseptic spools. For users of spools, the costs of a subsequent cleaning step are saved and the spools can be purchased germ-free.

Hafner says the company’s activities in this field are to be intensified. “Our move into cleanroom technology opens up for us as spool manufacturers completely new target groups and applications.”