Model 551 High Temperature Metering Pump uses stainless steel isolation diaphragms in a hydraulic manifold to separate the fluid being pumped from the driver pump. Therefore, the pump seals are always at ambient temperature and never in contact with the pump fluid. This combination insures a long seal life and trouble free operation at high temperature as well as the ability to pump a wide range of reagents. The front panel control allows the user to set flow rate, minimum and maximum pressure setting. The touch screen display reads out flow rate, minimum and maximum pressure, and operating pressure (digital transducer included). Remote hydraulic pump head allows portion of pump to be operated within oven or explosion proof compartment, while the control and electronics remain outside (1.5 meter maximum separation). This allows for the same flow control and programming features that we offer in our standard HPLC pumps, but at temperatures up to 200°C. Pump head heating options include oil gallery, electric heating element, or placement in customers oven. Combine two pumps together for high pressure gradient operation. This feature allows user to program changes in solvent composition over time period that ranges from 6 seconds to 999 minutes.