Technology News

TECHNOLOGY NEWS: MANUFACTURING EQUIPMENT

Downstream extrusion equipment from a supplier of auxiliary systems for plastics processors has been updated to satisfy the demands of extruders of medical tubing. Conair (Slough, Berks, UK; www.conairgroup.com) introduced improvements to its Medline cutter system as well as its vacuum tank at the Plastec West show in Anaheim, CA, USA, at the end of January.

The tubing pull-and-cut system was shown at the event with newly written software and advanced servo-drive technology. The software allows users to independently control the dimensions of up to eight lumens without experiencing delayed response times, diminished resolution, or a loss of repeatability. The unit also employs servo-drive technology to periodically adjust inner and outer diameters and to expand the tubing. The machine cuts the tubing with extreme precision, yielding a quasi-finished catheter component.

“Independent position-controlled servo drives on the upper and lower belts and twin in-line planetary gear reducers all but eliminate speed variation in the Medline puller,” says Bob Bessemer, downstream extrusion product manager at the company’s US headquarters in Cranberry Township, PA. The ability to control process variables, he adds, is a key demand among medical extruders.

At Plastec West, the firm also introduced an improved vacuum tank design that offers several features of interest to medical tubing manufacturers, according to Bessemer. Precision automatic vacuum control is particularly noteworthy, because it allows the user to adjust vacuum levels in the tank using a digital potentiometer.

“Digital vacuum control is inherently more accurate than analogue control,” says Bessemer, “but extruders prefer to make adjustments by turning a knob rather than entering a digital setting on a keypad. Depending on the application, the resolution of the potentiometer can be changed to fine or coarse increments,” he adds.

The interior of the tank has also been redesigned to eliminate nooks and crannies where bacteria and pyrogens may become lodged, and tubing guide rollers now flip out of the way to allow unimpeded access to the workpiece during start-up.