All-in-one medical tubing system delivers all the options.

By combining every feature requested by a group of medical extrusion experts, Conair Gatto of Bay City, Mich., has developed a completely preconfigured, ready-to-run downstream system for making small-bore tubing. "The guys we talked to are on the leading edge and we tried to give them everything on their dream lists," says extrusion systems manager Bob Bessemer. Conair introduced the Series 2000 HT Micro Bore system at NPE in Chicago last month.

Intended to replace free extrusion with a vacuum-tank system that fits within a clean-room environment, the all-stainless Micro Bore ships on a single base measuring only 7.5 ft long. Bessemer says it can produce single- or multi-lumen tubing with ODs up to 0.200 in. at rates up to 500 fpm in the smaller-diameter products.

One of the system's most critical components is a 4-ft-long, dual-chamber vacuum tank. It's essentially a half-scale version of Conair's patented High Technology Tank, though this smaller tank has several new features intended to minimize turbulence. For example, a newly designed "skimmer" tube draws thin sheets of water from the top of the tank, replacing conventional drains. Also, the heat exchanger is built into the tank's wall so that only small amounts of make-up water need enter the tank. And the tank's cantilevered rollers can be locked to prevent any movement that might induce turbulence.

A fine-toothed timing belt containing a non-stretching stainless-steel braid drives the Micro Bore's integrated puller, and a built-in Thermolator water-temperature controller from Conair Tempro completes the equipment package. For process control and SPC/SQC recording, the Micro Bore includes an on-board 486 PC, which also handles recipe storage and taper-tube programming. SQC capabilities include collection of many types of production data: The system can document the water and air flow rates, vacuum levels, puller speed, water temperature, and cut length associated with a given product.

USER'S CHOICE

In addition to the base system, the Micro Bore lets users easily add an array of options to create a more customized line. "Our market research told us that many commercial systems lacked that features that users care about," Bessemer notes. "And many potential users don't have the time or know-how to pull together their own systems from a variety of vendors." So Conair decided to offer every feature deemed important by a group of tubing producers surveyed by Bessemer before the design stage.

While not unusual when taken individually, these options are noteworthy for being supplied as part of a preconfigured package, eliminating the need for an expert to design a system from scratch. "You can essentially roll the Micro Bore off the truck, put it in line with an extruder and begin producing tubing," says Bessemer. Among these options are:

* A servo-driven, rotary-knife cutter that can run at up to 1000 cpm. It uses a planetary-gear reducer to get maximum power from a small motor running at high rpm.

* Various air-control kits to raise the Micro Bore's lumen capacity from one to five.

* A new process-water debubbling system to keep any bubbles from causing surface blemishes or interfering with ultrasonic gauging. The system relies on a water/air separation system located just after the water pump.

* OD/ID/wall-thickness gauges from Zumbach Electronics of Mt. Kisco, N.Y.; On Line Controls of Woburn, Mass.; or other user-specified suppliers.

* An optical system that measures diameter variations such as lumps and neck-downs.

* Taper/bubble controller and software.

* A potentiometer-based system for measuring the distance between die face and tank to [+ or -]0.001 in. for precision setup.