SMC's PA series process pumps now has a fluororesin bodied version, which
extends the applications of these compact and flexible units into areas
such as food processing and semiconductor manufacture. The new PA33/PAP33
series (PAP being the clean room version) are available in automatic (ie
non-electric control) and air-operated versions, the latter being
provided with a remote reset function as standard. In addition, the
air-operated type offers a stable performance, even at very low flow
rates or pressures, or when pumping gas entrained liquids. The discharge
rate, which can be as high as 13 litres/min, is easily controlled, while
repeated stoppages cause no problems for the pump.
PA series pumps are widely used to pump aggressive chemicals and
additives such as solvents and acids. One user recently placed a PA unit
on trial to test its capabilities transferring solvents. The most
aggressive solvents were used for the test, some of them being left in
the pump for up to 48 hours. With traditional pumps, this would have
required the replacement of seals in contact with these fluids.
We took the [SMC] pump apart, gave it a quick wipe around, and were
extremely impressed with the ease of maintenance, he reports. The
design includes features within the contact areas of the fluid chambers
that I have been seeking for my application - no sharp edges, adequate
radii at critical points, ease of cleaning and good sealing. Moreover, we
can use the same pump to feed solvent and/or water based materials. Such
a pump is difficult to find elsewhere.