Fully automatic coarse aggregate flow time measuring instrument

The coarse aggregate flow time measuring instrument is used to measure the time required for a certain volume of coarse aggregate to pass through a fixed size opening, indirectly evaluating the angularity of coarse aggregate. Suitable for measuring the angularity of coarse aggregates with a nominal maximum particle size of 9.5-19mm, the product complies with the mandatory industry standard JTG 3432-2024 "Test Code for Aggregates in Highway Engineering" of the People's Republic of China.

2. Structural characteristics of coarse aggregate flow time measuring instrument

The whole machine consists of a vibration table (including rubber suspension, vibration motor, base, etc.) and a flow device (including sample cylinder, guide groove, etc.);

⑵ Vibration table: A flow device is fixedly installed on the vibration table, and a bubble level is also set up;

There is a vibration motor suspended below. The vibration table is connected to the support frame through four rubber suspension devices, and the bottom of the support frame is a 100kg ± 10kg base.

⑷ Install the rotating shaft of the vibration motor horizontally, perpendicular to the axis of the guide groove;

⑸ The metal flip door controls the sample to slide out of the sample cylinder.

3Fully automatic coarse aggregate flow time measuring instrumentMain technical parameters

❶ Machine height: 1225mm;

❷ Base size: 400mm × 400mm, composed of a plastic sample cylinder and a metal guide groove, with a total mass of 42.3kg ± 0.1kg;

Inner diameter of sample cylinder: 125mm ± 1mm, height 610mm ± 10mm;

❹ Flow channel: inclination angle of 10 °± 0.5 °, internal width of 90mm ± 1mm, plastic edge embedded;

Adjustable opening of metal baffle: 42mm ± 1mm or 60mm ± 1mm;

❻ Collar angle: 10.0 °± 0.5 °;

Vibration motor rotating shaft: speed 2970r/min ± 20r/min;

Under no-load conditions of the flow device: frequency 50Hz, amplitude 0.18mm ± 0.02mm.

4. Test Procedure for Coarse Aggregate Flow Time Tester

4.1 Standard aggregate test

Before each formal test, the flow time of the standard aggregate should be measured first.

4.1.2 Adjust the support frame of the coarse aggregate flow time measuring instrument to make the vibration table horizontal. Set the opening to 42 ± 0.2mm using a height block

4.1.3 Start the vibration motor 5 minutes in advance during the test and maintain vibration throughout the entire test process.

4.1.4 Place the balance in front of and below the tester, and then place it on the receiving container so that the particles sliding down from the guide groove during the test can enter the receiving container, while the balance displays the mass of the falling sample. Reset the balance to zero. Close the flip door. Slowly pour the standard aggregate into the sample cylinder, ensuring that the surface of the aggregate is flat. However, after pouring, the surface of the aggregate must not be disturbed or scraped flat by any tool.

4.1.5 After vibrating the standard aggregate for 20 seconds ± 5 seconds, open the flip door to allow the aggregate to flow out of the sample cylinder along the inclined surface of the guide groove and into the receiving container. When the balance shows 1000g, start the stopwatch immediately; When the balance displays 1000+7000 × γ and/2.70, stop the stopwatch immediately and read the time as the flow time of the standard aggregate.

4.1.6 After the aggregate flows out, clean the sample cylinder, guide groove, and receiving container.

4.1.7 Repeat the test for the same aggregate according to sections 4.1.4 to 4.1.6 above, for a total of 5 measurements.

During the entire testing process, the ambient temperature should be maintained at 15-30 ℃, and the vibration motor should remain in a vibrating state until all tests are completed.

4.1.9 Take the average of 5 measurements and record it as F. If. When meeting the standard value of standard aggregate within ± 5s, set the opening within the range of 41 ± 0.2mm~43 ± 0.2mm, and retest according to the above method until the E measured by the set opening meets the standard value of standard aggregate within ± 5s.

If a suitable opening is not found to meet the standard value E ± 5s requirement for F, the coarse aggregate flow time measuring instrument should be discarded.

4.2 Sample Testing

4.2.1 For the 4.75-9.5mm and 9.5-13.2mm particle size aggregates, set the opening according to 4.1.9 and conduct the test according to methods 4.1.2-4.1.8.

4.2.2 For the 4.75-19mm particle size aggregate, set the opening to 60 ± 0.2mm and conduct the test according to methods 4.1.2-4.1.8.

5. Packing List for Coarse Aggregate Flow Time Tester

⑴ Host: 1 unit

⑵ User manual: 1 copy

⑶ Certificate of conformity: 1 copy

⑷ Warranty card: 1 copy