The 6400 Automatic Isoperibol Calorimeter represents the next evolutionary step in the Parr automated calorimeters. Inclusive and compact, the instrument incorporates a closed loop cooling subsystem into the calorimeter. This subsystem uses a thermoelectric cooler assembly attached directly to a one liter water tank which supplies cooling water to the calorimeter. An external nitrogen pressurized tank is used to supply rinse water to the calorimeter. This model features the fixed bomb and bucket design allowing for automated bucket and jacket fill as well as automated vessel fill and rinse. The 6400 requires one minute of operator time per test, allowing a technician to operate up to four calorimeters simultaneously.
Features and Benefits
Parr Fixed Bomb and Bucket Technology
The 6400 Automatic Isoperibol Calorimeter uses a fixed bomb and bucket design where the bomb and bucket are not removed from the calorimeter during routine operations. This design concept has made it possible to offer unique levels of automation for the entire calorimetric determination not just the data collection and reporting steps. The result of this automation will save approximately five minutes of operator time per test when compared to any removable bomb calorimeter.
Oxygen Charging and Release
The fixed bomb and bucket design allow the oxygen supply to be directed into the head of the bomb at the beginning of each test. The head of these bombs incorporate a check valve which dynamically seals when the bomb is pressurized. At the end of the test, the gases in the bomb are automatically released while the calorimeter is being returned to its starting temperature.
The bucket in these calorimeters has been designed to provide smooth circulation over the surface of the vessel. The design also repeatedly fills the bucket volumetrically. The bomb head closure seals the bucket at the same time the bomb is closed. This unique design minimizes the amount of water required for the test as well as permitting rapid, automatic and repeatable filling for each test. The water heated by the combustion is automatically drained from the bucket at the conclusion of the test and replaced with cooling water to bring the bomb and bucket rapidly back down to the starting temperature for the next test.
The 6400 Calorimeter features the patented closure design of the Parr Fixed bombs. This design allows the user to seal and lock the head into the cylinder with simple one sixteenth turn. The main bomb seal is an o-ring optimized to minimize frictional wear, improving the lifetime of this seal. At the conclusion of the test the inside surface of the bomb is washed to remove the products of the combustion from the bomb. The automation of the bomb washing step eliminates one of the most tedious and time consuming manual operations required with removable bomb calorimeters. Besides the elimination of the drudgery of manually washing the bomb, a not so obvious advantage of the fixed bomb design is that the bomb is always washed as soon as the final temperature can be determined. Generally, this is within 4-5 minutes of the time the bomb is fired. This holds to an absolute minimum the time any acids produced by the combustion can attach to the inner surfaces of the bomb. This has improved the service life of these bombs in comparison to removable bombs.