BS EN 12846-1:2011 pdf download

BS EN 12846-1:2011 pdf download.Bitumen and bituminous binders- Determination of efflux time by the efflux visco meter Part 1: Bituminous emulsions.
NOTE 2 The viscomeler cup should be provided with a lid suitable for clostig the upper end of the cup without touching the test material when the cup is filled. This lid is provided with a central hole throt4 which the thermometer cat pass and with a groove on one side through wtiidi the rod of the valve cat pass
6.2 Vlscorneter water-bath, constant temperature for maintaIning the lest temperature to within ± 0,5 C. A typical elevation and a plan of assembled viscometer are given In Figure 1.
6.3 Temperature controlled water bath, maintained at (40,0 ± 0.5) C. ii which one or more of the viscometer cups can be immersed up to the rim of the cup.
NOTE 1 Other test leniperalures are (50.0 t0.5YC or (25.0 ± 0,5) C.
If a multiple-cup heating barn Is used, the cups shall be separated from each other and from the walls of the bath by at least 55 mm.
A suitable support shall be provided to maintain the cup(s) in a vertical position.
An appropriate climatic chamber may be used for low breaking Index emulsions (see 8.3.4).
NOTE 2 The viscometer water bath (62) may also be used to directly condition the test sample in the cup.
6.4 Thermometers, two, conforming to the requirements described in Annex &
Other temperature measunng devices may be used instead of mercury stem thermometers. However, the mercury stem thermometer Is the reference device, Therefore any alternative device employed shall be calibrated so as to provide the same readings as would be provIded by the mercury stem thermometer, recognising and allowing for the fact of changed thermal response times compared with the mercury thermometer.
When measuring and controlling nominally constant temperatures, as in this test method, alternative devices can indicate greater cyclic variations than mercury thermometers, to an extent depending on the cycle time of heating and the power of the controlled heat input.
6.5 ReceIver, consisting of a 100 ml cylinder with graduations at 20 ml. 25 ml and 75 ml. complying with the requirements of EN ISO 4788.
6.6 Timing device, capable of measuring the efflux time with an accuracy of ±0,2 s.
7 Sampling
The material under test shall be sampled in accordance with EN 58 and prepared in accordance with EN 12594.
The test shall be carried out in duplicate.
8 Procedure
8.1 General
Carry out the procedure in laboratory at room temperature between 18 C to 28 ‘C.
8.3.5 If a separate water bath is used (63), remove the filled cup from the water bath and place It into the viscometer cup holder. Check that the sample is maintained at the required temperature. If not, wait till equilibrium at test temperature is reached again
8.3.6 Remove any excess emulsion sample while removing the thermometer so that the fInal level of the lander is on the centte line of the levelling peg when the rod of the valve is in a vertical position. Reniove the cork or stopper.
8.3.7 Pour the light mineral oIl (5.1) or solution Sa (5.2) or solution S (5.3) Into the receiver (6.5) up to the 20 ml graduation mark and place the receiver (65) directly under the orifice of the cup. Lift the valve and suspend it on the valve support such that the peg Is levelled with the upper edge of the cup of at least 16 mm. Start the timing device (6.6) when the liquid in the receiver reaches the 25 ml graduation mark and stop it when the liquid reaches the 75 ml graduation mark.
Record the effiux time to the nearest 0,2 5.
8.3.8 Repeat Sampling (Clause 7) and Procedure (Clause 8) steps on a second emulsxn test sample.
9 Expression of results
Express the resull as the arithmetic mean of the two results obtained in accordance with Clause 8 to the nearest second, provided that individual results do not differ by more than the value for repeatability given in Table 2 under Clause 10.
If the two results differ by more than the above specified values, repeat the whole procedure.
10 Precision
10.1 General
The precision of the method was evaluated with 4 mm and 10 mm cups only. With the 2 mm cup, the
precision Is not available.
10.2 RepeatabIlity
The difference between two successive test results, obtained by the same operator with the same apparatus under constant operating conditions on identical test material would, in the long run, in the normal and correct operation of the test method, exceed the following values in only one case in twenty.