Injection molded medical clamp weighs just 0.003g

A medical clamp with a part weight of 0.003g will be manufactured from polyacetal supplied by Ticona in a cycle time of 4  seconds in a demonstration at the German medical show Compamed being held in Düsseldorf Nov. 16-18.

Molded medical clamp is made with polyacetal.

The part will be molded on a MicroPower 15/7,5 from Wittman Battenfeld with a four-cavity mold from Microsystems UK. The MicroPower is sold in a clamping-force range from 5 to 15 tonnes.

"This innovative two-step injection unit, consisting of a screw and a plunger, with a shot volume ranging from 0.05 to 4 cm³, injects thermally homogeneous melt, with the result of premium-quality parts from absolutely stable production with short cycle times," a spokesman for Wittman Battenfeld said.

Special auxiliaries

Its peripheral equipment is adapted to produce nano and micro parts. In the upcoming demonstration at Compamed, the parts are removed by a W8VS2 Wittmann robot. As part of a quality control system, the parts are then passed on to a camera integrated in the production cell and in the machine's control system for quality inspection. The parts are subsequently separated according to cavities and stacked in a stacking module.

The machine's clean-room module provides clean air class 6 according to ISO 14644-1, according to Wittman Battenfeld. In such applications, the parts are injection-molded, inspected and deposited within the clean-room compartment.

In a separate demonstration at the show, paper clips will be produced on a MicroPower 15/7,5 with a six-cavity mold from Microsystems UK in a cycle time of  four seconds.

The finished parts will be ejected in free fall onto a conveyor belt.

There are no commercial applications to date for the part, but two companies are showing interest.  One is producing vascular clamps. The other one (an American company) is producing clamps for skin closure after surgery. A Wittman Battenfeld spokesperson said  the names of the companies could not be disclosed due to confidentiality agreements.