摘要 |
<p>A pneumatic pumping device incorporating a movable valve such as bellows (4), diaphragm driven by air back pressure in a cylinder (3) so that a liquid is inhaled and discharged by reciprocating movement of the movable valve, and in which surfaces contacting the liquid on the internal and external parts of the pumping device are formed of either a single substance or a compound of a fluororesin such as PTFE, PFA, CTFE in order to feed strong acid liquid or strong alkaline liquid without corrosion on components of the pumping device.</p> |