All equipment and components listed in the specifications below must be as named or MNDOT approved equal. Asphalt Content Furnaces (Barnstead/Thermolyne Asphalt Content Tester - Model F85938X) or MnDOT Approved Equal The unit shall consist of National Center for Asphalt Technology (NCAT) Asphalt Content Tester that combine a furnace with an internal weighing system that constantly monitors weight loss during burn-off to determine asphalt content of asphalt mixtures in accordance with ASTM D 6307 and AASHTO T 308 and that conforms to all the following requirements and specifications: • Shall be a forced air ignition furnace capable of maintaining a temperature of 6500 C (1200 0 F). Shall also be capable of maintaining other set temperatures. • Shall be equipped with an internal balance, thermally isolated from the furnace chamber, capable of weighing a 5000-gram sample in addition to the sample basket. Endpoint sensitivity must be within 0.01%- 0.5% of sample weight. • Shall calculate a temperature compensation factor for the change in weight of the sample baskets and provide for positive or negative input of aggregate calibration factor. • Shall provide printed results that include: initial specimen weight, specimen weight loss, temperature compensation, correction factor, corrected asphalt content in percent, test time and test temperature. • Shall have a minimum sample chamber of 355 x 266 x 355mm (14" x 14” x 14") (W x H x D). • Sample stability is reached once endpoint criterion is met for 3 consecutive minutes during the test. • Shall have automatic endpoint detection within 0.01% and software ends the test, prints the results and beeps until STOP is pressed to unlock door. • Shall have a safety door lock that prevents access during operation. • Shall be equipped with a 24 hour/7day timer.
