Chemical resistance of AFM 34
Chemical resistance of AFM 34 as a survey list
Important notes about using this list
Only the chemical resistance of AFM 34 is described. Questions concerning sealability or Codes of Practice are not discussed, as these depend on the relevant operating conditions.
 
Source of the data
The data are based on experience, literary research, and laboratory tests. Partially, they are analogous conclusions. Therefore, no warranty can be accepted for individual applications, as chemical resistance also depends on the installation conditions. Tongue-and-groove flanges and/or very high surface pressures increase operational safety. Conversely, lower surface pressures and/or gasket thicknesses above 2 mm reduce the operational safety and sometimes the max. permissible temperature.
 
Temperature limits

The specified temperature limits for which AFM 34 is classified as resistant, are empirical values and should not be considered as absolute upper limits. The specified limits ensure a high safety margin, also with sub-optimal installation conditions.
 
In individual cases, the operating temperatures can therefore be considerably higher than specified in the list.
 
An increase of the temperature limit by max. 50 °C (but not higher than 250 °C, or 200 °C with water and steam) is possible if gaskets with inner beads of stainless steel (1.4571) are used, provided the bead itself is not attacked.
 
An increase of the temperature limit by max. 100 °C (but not higher than 300 °C, or 250 °C with water and steam) is possible if gaskets of reinforced AFM 34 METALL with inner beads of stainless steel (1.4571) are used, provided the bead itself is not attacked.
 
For acids and acid halides at higher temperatures than specified, the use of PTFE sheathing or pure PTFE gaskets is recommended, e.g. expanded PTFE such as REINZOFLON E.
 
For mixtures and solutions that do not form reaction products (as is the case with aqua regia, for example), the maximum operating temperature is determined by the lowest temperature of the constituent components, provided the latter is present in an appreciable quantity.
 
Reference values:
Acids and acid halides > 1 %
Other chemicals > 5 to 10 %
 

Media not listed: Analogous conclusions and effects
For chemicals not listed here, we recommend checking under products of the same homologous range, i.e. combinations with one or more CH2 groups, or under isomeric products, whereby the number, type, and distribution of the substituents must be the same. For example, instead of octane, you can check under isooctane, heptane or decane. However, instead of ethyl nitrite you may not look under nitroethane.
 
To remain on the safe side in case the substituents of a non-listed product are also different, please note that the operating temperature can be reduced up to 50 °C for every additional phenolic OH, ONO, NO2, NH2, Cl or COOH group.
 
TA air
AFM 34 and the version with stainless steel inner beading (AFM 34 CO ME) are TA air certified.

Warranty claims
The specified data have been compiled to the best of our knowledge. They are valid for the material "as delivered", without any additional treatment. In view of the many possible installation and operating conditions, definitive conclusions cannot be drawn regarding the behaviour of a sealed joint in every application. The data cannot be used as a basis for any warranty claims.