Track, ditch and pipeline layout in roadway design

1. Track layout:

The roadway track consists of three parts: rail, sleeper and ballast (Fig. 1). Different types of rails should be selected for different roadways. The sleepers and ballasts should be compatible with the type of rails (for the table, please refer to the previous article “Flat Section Dimensions”).

The wooden sleeper specifications of the downhole narrow-track line usually have a length of 1200mm. The upper width, the lower width and the height are 120mm×150mm×120mm and the length is 1200mm, and the upper and lower widths and heights are 130mm×160mm×140mm, respectively, for 15- Rails of 18kg/m or 24kg/m with a gauge of 600mm or 900mm. In order to save wood, reinforced concrete sleepers have been widely used in mines in China. The specifications of commonly used reinforced concrete sleepers are shown in Table 1.

2. Ditch layout:

The ditch layout should follow the following principles: The ditch should generally be placed on the side of the sidewalk, and its slope is the same as the slope of the roadway, which is 3‰-5‰. The ditch shall be covered with a cover plate, and the reinforced concrete prefabricated plate is often used as the cover plate; when the concrete is supported or not supported, the slope of the ditch side is generally 1:0.1-1:0.25; the fullness of the ditch is 0.75; The maximum flow velocity in the ditch: 5-10 m/s for concrete support and 3-4.5 m/s for unsupported; the minimum flow rate of the ditch should meet the requirements for non-precipitation of mud. The size of the ditch is selected according to the amount of water flowing through the roadway and the slope of the roadway (Fig. 2, Table 2).

3 pipeline layout:

It is often necessary to arrange various pipelines in the roadway, such as pressure air pipes, drain pipes, water supply pipes, cables, and the like. The layout of these pipelines should be considered for production safety and ease of inspection and maintenance of workers. In the main transportation roadway and return airway, the laying of pipelines should meet the following requirements:

1 Under normal circumstances, the pipeline is located on the side of the sidewalk, and the erection of the pipeline can be carried out by means of pipe piers, brackets or bolts.

2 The power cable and signal cable should not be located on the same side. If they must be on the same side, they should be suspended separately. The power cable is below and maintain a distance of more than 300mm. When the cable is laid in parallel with other pipes, the cable should be hung above the pipe. And separated by a distance of more than 300mm.

3 The cable suspension height should ensure that the cable will not hit the cable when it is dropped, and it will not fall on the track or the transportation equipment when the cable falls.

The piping arrangement in the transportation lane is shown in Figure 3.

4, wind speed check: Because the wind speed in the roadway over the assembly to raise dust, affecting workers' health and work efficiency, the mine safety regulations stipulate the maximum wind speed allowed by the roadway for various purposes. The wind speed mine calculation formula can be written as:

V=Q/S≤V

Where Q--the air volume passing through the roadway, m3/s;

S--the net area of ​​the roadway, m2

V allowed - the maximum wind speed allowed to pass, m / s.

After the check, if the wind speed exceeds the maximum allowable wind speed, the section size should be modified.

API

Penicillin and cephalosporin Beta-lactam antibiotic products include 16 varieties of API and intermediates. The penicillin series includes penicillin G potassium crude, penicillin G potassium, penicillin G sodium, 6-APA, amoxicillin trihydrate, ampicillin trihydrate and ampicillin sodium.
The cephalosporin series includes intermediate 7-ACA, cefazolin sodium, cefazolin acid and ceftriaxone sodium. Meropenem API is also produced.