| In this new age of scientific instrumentation and | | | | withstand possible hazardous substances, and not |
| analysers, the need for fluidics management at an | | | | lose their functionality in the exposure to |
| increasingly accurate rate has eclipsed the | | | | excessive heat or cold. The valve timing must be |
| standardized pumping methods used in the past. | | | | efficient and cause a steady flow of air, fluid, or |
| High-capacity diaphragm pumping stations in the | | | | gas without interruption or surges. |
| analytical laboratory are needed for the efficient | | | | Some diaphragm pumps are used for the |
| operation of many instruments and analyser, as | | | | negative pressure, as in vacuum systems used in |
| they depend more and more on mechanical | | | | chemistry or hematology analysers. Reservoirs |
| methods for fluid and gas movements throughout | | | | are used to maintain a constant vacuum after the |
| the systems. | | | | pump has reached the required pressure, so the |
| Different pumping methods exist, and each | | | | pump is only activated at times when the |
| presents its own set of problems encountered by | | | | negative pressure reaches undesirable levels. The |
| laboratory personnel. Finding a good match for the | | | | diaphragm pump must withstand on-and-off |
| needs of your laboratory does not have to seem | | | | operation at different times, and the motor must |
| so daunting, as there are so many systems from | | | | be a quick-response electric with auto-shutdown if |
| which to choose. Finding the pumping system for | | | | overheating is reached. |
| the analysers and other instrumentation of the | | | | Diaphragm pumps come in two styles: Single head |
| laboratory can be just a matter of how you | | | | and double head. The single head can have |
| operate fluidics or liquid handling, or what type of | | | | different capacities, ranging up to 100 InHg, or 7.0 |
| analysis is predominant in the laboratory. One of | | | | Bars. This is excellent for the operation of several |
| the best methods for fluid management is the | | | | instruments that require positive pressure in their |
| diaphragm pump. | | | | reservoirs. As far as vacuum, a capability of 1000 |
| The diaphragm pump is a deceptively simple | | | | Mbars should be available with an excellent |
| design. A diaphragm, or membrane, is positioned in | | | | diaphragm pumping system. |
| a pumping chamber, usually form-fitted to achieve | | | | A dual-head diaphragm pump can provide even |
| efficient gas or fluid movement. The membrane | | | | more pressure and ultimate vacuum to handle |
| can be made of a thermoplastic, rubber, such as | | | | just about any need. These larger, high-powered |
| latex, or a PTFE impregnated plastic. The flexibility | | | | units have two diaphragms functioning in tandem, |
| is not as important as the materials ability to | | | | so that the flow rate through tubes is constant |
| withstand against high temperatures, caustic or | | | | and controlled. With gauges and relief valves, |
| acidic chemicals, or acidic vapors. The diaphragm | | | | there can be no doubt about the performance of |
| must be able to run indefinitely without concern of | | | | these versatile and precision pumping systems. |
| overheating or general wear over short periods. | | | | Diaphragm pumps are the systems of choice for |
| The valve system must also follow certain | | | | many research and medical laboratories around |
| guidelines for safety and flow control. The valves | | | | the world. |
| must be made of materials that can also | | | | |