MANUFACTURING
Extruded medical tubing dates back to the 1930s. At that time, use of catheters was limited. Most catheters were made by the tedious method of wrapping nylon, cotton or silk over a music wire mandrel, then coating and baking it one layer at a time to produce the desired thickness. As the uses for catheters and tubing in general increased so did the demand for more production. This need accelerated the medical tubing business.
Tubes at the time were fitted with connectors to join them to the supply, suction device or pump that motivated whatever was to pass through them. The process of joining the tube to the connector introduced other possible flaws in the overall product such as steps or flashing. It became desirable to eliminate or limit the use of connectors and extrude the tube with the diameter required for the connector incorporated within its length.
The first tube of this type made in the United States was developed in a small factory in Argyle, New York, in the late 1950s by Dave Sheridan. Sheridan discovered that by stopping the internal airflow in a tube while it was being extruded, caused a bump in the outside diameter. He went on to develop the process by controlling the airflow and at the same time, controlling the extrudate speed to develop the size and shape of the bubble required. Sheridan’s discovery led to an ever-increasing amount of catheters and other types of tubes such as
• tubes for intravenous sets for continuous medication
• continuous taper tubing for ease of catheter insertion, single or multilumen
• inset bump tubes for use as suction devices
• continuous tubing with multiple bumps that can be cut to length.
