Minimum recoverable coal layer thickness and determine the boundary line 4. Infinite inference There are no other engineering points beyond the visible coal engineering site. In this case, the extrapolation is based on geological data. This kind of inference method should fully consider the factors such as the genetic type of the coal producing area, the coal-bearing construction characteristics and the stability of the coal seam. (1) Extrapolation method. In the calculation of detailed and intensive reserves, it may be encountered that there is no other project besides the advanced reserves (A or B), but it has not yet reached the exploration boundary. At this time, it is generally necessary to extrapolate a certain distance to calculate the reserves. The method is to extrapolate the B-level reserves in the stable or relatively stable coal seam area at the periphery of the A-stage block, not exceeding the A-level basic line distance of 1/4 ~ 1/2; or in the engineering-controlled B On the periphery of the block segment, the C-level reserve is extrapolated at a distance not exceeding 1/4 to 1/2 of the B-level basic line. According to the regulations, it cannot be continuously extrapolated. Unstable coal seams are generally not extrapolable. (2) Morphological method. It is based on the change of coal seam morphology and is suitable for coal seams with thick coal seams and large thickness variations. 1 section method. On the survey line profile, the coal seeing point and the stop coal point of the known engineering point (that is, the top and bottom of the coal seam) are respectively connected, extended and then rendezvated at one point, and the point of vanishing points on several sections is connected. The pinch line of the coal seam is shown in Figure 2-8-10. Figure 2-8-10 Schematic diagram of determining the point of extinction of coal seam by section method 2 contour method. Assume that the thickness of the coal seam is changed regularly. According to the known engineering points, the thick line diagram of the coal seam can be made. In the normal direction of the isobaric map, there is a law that can be found, and the law can be found according to the law. Take the thickness point and the coal seam tipping point, and connect the corresponding points on each normal line. As shown in Figure 2-8-11. Figure 2-8-11 uses the equal thickness line method to determine the zero boundary line 1 a hole and see the thickness of coal; 2 - the thick line of the coal seam that has been explored; 3 - the thick line of the coal seam extrapolated; the boundary line of 4 - zero point; 5 - the coal seam that has been explored; Coal seam continuation end feed Bronze Fittings is designed according to kembla and connex type .but the quality is same as kembla bronze fittings and coneex bronze fittings,End Feed Bronze Fittings,end feed gunmetal fittings,kembla bronze fittings,connex bronze fittings End Feed Bronze Fittings,end feed gunmetal fittings,kembla bronze fittings,connex bronze fittings Taizhou Runde Company , https://www.zjbronzefittings.com