Selecting the right pneumatic valve that can be beneficial to your machine requires 3 important things:

Shifting Forces: In order to ensure a reliable valve, high shifting forces are required.  A valve with higher forces will shift through more contamination throughout its life.  How can you determine shifting forces?  Speed.  Higher forces result in faster speeds. Fast valve = High shifting forces = A more reliable valve.

Balance: In many applications, it is critical that the same result happens each time a valve shifts.  A filling machine must fill bottles to the same levels.  A glue dispensing gun must place a glue dot in the same place every time.  A sorting machine must eject bad parts consistently.  In order to do this, a valve must be repeatable at all pressure levels.  This is especially important to compensate for variations in pressure during normal plant operations.  This attribute is referred to as a “balanced design". 
 
Balanced design = Repeatability = A more reliable valve.

Orifice size: The larger the orifice in the valve is, the less likely the valve is to get clogged and not function.  Try looking at filter specs to see where manufacturers believe the problems start for their orifice.  For instance, a 40 micron spec would indicate a larger orifice than a 5 micron spec.
 
Shifting forces, balance, and orifice size are all important in selecting the right product for you.  Contact Pneumatic Solutions Australia to discuss these factors with one of our pneumatic consultants and for a free product demonstration!