Since the revision of the calculation standard EN1591 (2014 version), pressure has strongly increased to improve certain parameters by the manufacturers of PTFE sheets and gaskets.

The revised version of this standard demands substantially improved mechanical material properties for successful flange calculations. In particular, the flow behavior has a great influence on the calculations as well as on the maximum permissible surface pressure.

The significant improvement in the new Teadit 30 SH ePTFE gasket sheet is credited to a much more homogeneous and considerably finer fibrillation. The VCI (German Chemical Industry Association) guideline for flange assemblies requires Appendix C“ a minimum PQR value of 0,45 (under maximum operating temperature). On this basis, Teadit 

30 SH meets the requirement with a maximum permissible operating temperature for PTFE i.e. 260°C. Filled restructured PTFE materials, as well as other expanded PTFE sheets simply cannot keep up with these requirements.

The strategic improvements of the new Teadit 30 SH material are also reflected in the maximum permissible gasket stress Qsmax. According to EN13555 the shrinking of the inner diameter must be considered for Qsmax determination. While the Qsmax value for most PTFE gaskets has to be significantly reduced, particularly at elevated temperatures, this is not the case with Teadit 30 SH gaskets!

The data-sheets according to EN13555 have already been uploaded at http://www.gasketdata.org/ or on our 30SH Product Page where you can see the outstanding mechanical properties of the product. 

All relevant approvals for the new Teadit 30 SH - like TA-Luft, safety of blow-out, FDA and 1935/2004 - are already available. Teadit 30 SH sheets are available on short call, both in printed and/or embossed version.