Originally Published EMDM
January/February 2004
Technology News
Two-Component Mould Eliminates Syringe-Plunger Assembly Operations |
| By eliminating the manual assembly of syringe plungers, a moulding process reduces the product’s exposure to contaminants. |
A two-component mould that fabricates syringe plungers does away with the need to assemble plunger bodies and their tips. The tips are moulded first, after which they are transferred to plunger-body mould cavities. Each cycle produces complete plungers, thus reducing contamination concerns. Mould and die maker Boucherie (Izegem, Belgium) has a patent pending for the process.
“The part is never cleaner than when it falls from the mould,” says John C. Williams, manager of the company’s US plastic technology business unit. “By eliminating a step in the assembly process, we have reduced the product’s exposure to contaminants.”
The absence of visible injection points and parting lines is cited as another benefit of the process. It also creates a permanent bond between the plunger tip and syringe body. In addition, says Williams, “we can achieve very fast cycle times, in some cases under 7.5 seconds.”
The plunger tips are made from Santoprene TPE 8281-55 from Advanced Elastomer Systems (Brussels). The material complies with ISO 10993 and USP Class VI guidelines, is latex free, and is compatible with most forms of sterilization. Its compression set ensures reliable sealability, and it withstands exposure to a range of temperatures.
Boucherie also recently announced the development of a shuttle mould that, it says, may have medical product applications. An external station cools the first-shot moulded parts, shuttles them to the overmoulding cavities, and removes the finished parts.
The mould is designed in a stack configuration. This enables the use of a high-cavitation mould with a standard clamp and small press. Because it allows for short cycle times, the shuttle mould is suited for high-volume production processes, according to the firm.
Norbert
Sparrow
Copyright ©2003 European Medical Device Manufacturer
