中国·永利y23455(股份)有限公司

The Automatic Coarse Aggregate Angularity Tester can test the angularity of coarse aggregates with particle sizes ranging from 4mm to 20mm according to EU standards (the Chinese standard is 4.75mm to 19mm). The test results can further be used to control the quality of aggregates according to the control indicators in the new JTG F40 Technical Specifications for Construction of Asphalt Pavements.

Compared to traditional semi-automatic testing equipment, the "fully automatic" coarse aggregate angularity tester can automatically start the timer when the mass of the aggregate entering the receiving container reaches 1000g. The timer stops automatically when the balance reading reaches $1000 + \frac{7000 \times apparent relative density of the aggregate}{2.70}$ , calculating the flow time. This eliminates the operational errors introduced by manual stopwatch timing methods required for imported equipment. Therefore, during the test, the operator only needs to input the apparent relative density of the aggregate in advance, load the sample, and start the equipment to automatically complete the test.

The height of the opening can be flexibly adjusted:

For aggregates with particle sizes of 4.759.5mm and 9.513.2mm, the opening height is 41±0.2mm ~ 43±0.2mm.
For aggregates with particle sizes of 4.75~19mm, the opening height is 60±0.2mm.

Standard Samples of Coarse Aggregate

The standard samples are made from pre-selected aggregates that have been crushed, naturally dried, sieved, and uniformly mixed before being packaged in polypropylene barrels, each containing 10kg. These samples are calibrated by the Key Laboratory of Road Structure and Material of the Ministry of Transport's Highway Research Institute and come with a certificate.

The validity of the standard samples is 20 uses. After 20 uses, a comparison test should be conducted with new standard samples. If the difference in flow time between the two samples exceeds 4 seconds, the old sample should be discarded and replaced with a new one.

Note: The typical nominal value of the standard aggregate is 113 seconds, with an uncertainty of 0.289 seconds (subject to the actual certificate indicators).