BS EN 58:2012 pdf download – Bitumen and bituminous binders — Sampling bituminous binders

BS EN 58:2012 pdf download – Bitumen and bituminous binders — Sampling bituminous binders lf samples of flowing material are to be taken from narrow pipes,e.g. on mixing plants, the installation of aneasily accessible 3-way valve is convenient. The cock shall have an internal diameter appropriate to the sizeof the pipe, and shall be installed with the sampling outlet pointing downwards. The length of the pipe leadingto the outlet shall be as short as possible. Figures 6 and 7 show an example of a three-way valve. Necessity to draw off material should be assessed (see 8.1.1 above). lf a representative sample is to be obtained, several spot samples shall be taken by opening the three-wayvalve at equal time intervals over the whole supply period. This method is suitable for all liquid materials in narrow pipes. For well-mixed materials, a spot sample can be regarded as a representative sample, but for materials whichare not well mixed, a composite sample shall be formed from at least three spot samples. lf a well-mixed material is unloaded from a container vehicle, the sample shall be taken during the delivery ofthe second third of the material. 8.2Sampling using submersible equipment The procedures described in 8.2 use permanently installed sampling devices and the depth from which thesample is taken is therefore fixed in advance without reference to the depth to which the tank may be filled atthe time of sampling. By the use of submersible equipment, samples can be taken from any depth. 8.2.1 Weighted sampling can. A weighted sampling can shall be used for sampling liquid materials and atypical example for high viscosity materials is shown in Figures 8 and 9.For very fluid materials, a weightedsampling can of the type shown in Figure 10 may be used. Clean the sampling can and close it with the bung; lower it by the suspension to the chosen depth in the tank.Take a layer sample by withdrawing the bung with a short jerk on the suspension.The sampling equipmentshall then be held at a constant depth until it is full as indicated by a cessation in the formation of air bubbles. NOTE The opening in the flask or can is small in comparison with its volume, so that there is no significantcontamination of the sample by material from other layers during the subsequent slow withdrawal of the samplingappliance. The method is suitable for sampling fluid material in a storage...