Diaphragm pumps have established themselves as the preferred source of vacuum for laboratories. They do not contaminate your media, can be supplied with universal chemical resistance, are maintenance-free, gas-tight, and flexible. But when gases with a high moisture content need to be evacuated – in vacuum drying for example – condensation can collect in the pump head resulting in reduced flow and longer evacuation time increases.
To alleviate this problem, KNF has engineered into Selected diaphragm vacuum pumps an ingenious drying system. With these new self-drying pumps, it is possible to blow condensate at high speed out of the pump head without disruption to the evacuation process. To do this, the pump head is vented to atmosphere by means of a solenoid valve, while the vacuum in the sample chamber remains constant. After the pump head has been dried, the pump produces much better vacuum, and evacuates noticeably quicker than a pump without the drying system.
The drying system – patent pending – operates independently of the pump and is switched on, when re-quired, by a switch on the control panel. When the drying system is not switched on, operation of the pump is conventional. The drying process can be automatically controlled to meet the needs of various laboratory processes.
The range of Self-Drying Pumps is comprised of four chemical-resistant pumps with flow rates between 20 and 80 l/min (measured with air at 20°C and atmospheric pressure), and ultimate vacuums between ≤ 10 and ≤ 4 mbar abs.