BS EN 12697-39-2020 pdf free download.Bituminous mixtures — Test methods Part 39: Binder content by ignition
5 Apparatus
5.1 Furnace.
5.1.1 Furnace, capable of burning all the binder with the features detailed in 5.1.2 to 5.1.6 for Method A and 5.1.2 to 5.1.4 for Method B.
NOTE The temperature required to burn all the binder will depend on the technology used and is determined as part of the calibration procedure (see Annex A).
The furnace should not operate at its maximum capacity in order to allow flexibility and to ensure long service.
5.1.2 Sample chamber, having an internal capacity capable of taking the sample without touchingthe sides and with the maximum dimensions not greater than twice the minimum dimensions.
NOTE Larger chamber sizes can expedite testing by allowing larger sample basket(s) (and thus the material to be tested can be placed in thinner layers).
5.1.3 Automatic lock, that shall not allow the door to be opened until the completion of the test procedure, and a warning system to indicate the end of the pre-programmed temperature cycle.
5.1.4 System for reducing furnace emissions, by which the furnace shall be vented into a hood or to the outside and which, when properly set up, shall permit no noticeable odours escaping into the
laboratory.
The furnace shall have a fan with the capability to pull sufficient air through the furnace to expedite the test and to reduce the escape of smoke into the laboratory.
NOTE The method for reducing furnace emissions can comprise a filter and a post combustion chamber that is designed to eliminate the toxic residues produced by burning the binder.
If mechanical ventilation is used, the air flow should be adjusted so as not to affect the operation of the equipment (e.g. a forced air extraction system may result in a loss of fines and the generation of fumes rom the furnace).
5.1.5 Internal balance, capable of detecting mass variations of ± 0,1 g in the sample within the baskets.
The balance shall be thermally isolated from the furnace chamber.
5.1.6 Data collection system and a warning system, which shall be capable of being set to a value such that the loss in mass between individual readings taken at 1 min intervals for three consecutive minutes at end of the pre-programmed temperature cycle is not higher than the values stated in Table 1.
5.2 Metal baskets, manufactured from perforated sheet of tempered stainless steel or other suitable material that permits adequate air flow through the sample and retains the majority of the sample throughout the test.
The dimensions shall be specified by the furnace manufacturer to provide the maximum surface area for the sample while still providing sufficient room to safely load and unload the sample. The baskets shall be capable of being nested.
5.3 Catch pan, made of stainless steel with dimensions sized to accommodate the metal baskets specified in 5.2.
5.4 Oven, with convection or forced draft, capable of maintaining a temperature of (110 ± 5) °C in the vicinity of the samples.
5.5 External balance, capable of weighing the mass of trays plus the catch pan and the test sample according to Table 1 to ± 0,1 g.
5.6 Safety equipment, including safety glasses or face shield, high temperature gloves, and long sleeved jacket.
5.7 Heat-resistant surface, capable of withstanding 650 °C and able to act as a heat sink that can speed the cooling of the sample baskets, and protective cage, capable of completely surrounding the sample baskets and preventing accidental physical contact with them.
An appropriate sign warning of the danger of ‘Very Hot Surfaces’ should be attached to the protective cage.
5.8 Pan, larger than the sample basket(s), for transferring samples after ignition.
5.9 Spatulas.
5.10 Bowls.
5.11 Wire brushes.
6 Preparatory treatment of laboratory samples of bituminous mixtures
6.1 Sampling shall be performed in accordance with EN 12697-28 to achieve a sample size as given in Table 1. The mass of the sample in the baskets during the test shall be the same as the mass used for the calibration to ± 100 g.BS EN 12697-39 pdf download.