As loose PTFE brands hit the market, volumetric dosing of PTFE powder into the mold cavity  became possible. This created conditions for implementing the automatic molding process which is mainly used for fabrication of those parts which generated lots of cutting waste during the billet machining process.

 

It has now been proven that the automatic molding method is a cost-efficient solution for mass production of small-size parts with a weight of up to 50 g.

 

The automatic molding method enables finished parts such as O-rings, washers and valve seats to be made from PTFE-A by pressing PTFE in molds congruous to the finished part. The use of this process provides opportunities for:

 

reducing fabrication costs through material savings and efficiency improvements;

fast bulk fabrication (with an output of 15-30 pcs per minute);

fabrication of complex shapes with additional machining.

PTFE-A processing method based on automatic molding is used for fabrication of large runs of medium-precision parts. Dimensional tolerance for automatically molded PTFE parts is +/-0.2 mm.

 

It is cost-efficient to use this process for fabricating seats and rod gaskets for DN10-40 ball valves where the demand exceeds 30,000 pcs/month.