On the selection and calculation of drive systems for JMS type buried scraper conveyors

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Recently, the assembly drawings for several buried scraper conveyor units are being refined. Compared to scraper conveyor manufacturers, engineering design firms produce such assembly drawings in a much more general manner ； For example: detailed parameters such as the shaft journal through which the scraper drive spindle extends, and the diameter of the pitch circle of the internal drive sprocket – data that cannot be found in the \"Manual for the Design of Transport Machinery\". So, I’ve listed my questions in the hope that everyone can help: Given the operating speed of the scraper chain, its capacity to transport materials, and the pitch circle diameter of the main sprocket of the scraper chain, it is possible to determine the motor power, which can be calculated using standard formulas. However, the speed ratio of the reducer is unknown. The small sprocket mounted on the reducer’s output shaft, as well as the large sprocket used for the main drive of the buried scraper, both require selection, and their values are uncertain. a. Individually, the selection is made as follows: first, calculate the conveying capacity of the scraper, and then determine what specification of scraper to use ； Then the motor power is calculated ； Based on the motor power, select an appropriate reducer; first determine a gear ratio based on experience, then fit the small sprocket according to the output shaft of this reducer. The size of the large sprocket is determined based on the equal linear speed of the chain drive and the angular velocity of the main shaft of the buried scraper. b. Here’s the problem: First of all, there are no detailed standards for sprockets. It can be said that aside from having the same number of teeth and module as required by the design specifications, the inner diameter and outer thickness of the sprockets manufactured by different companies vary. Do I need to create separate part drawings to describe these details of the sprockets? c. Similarly, I actually select the components based on the manufacturer’s standards for sprockets, taking into account the shape of the sprocket, its pitch circle diameter, and its inner diameter. However, such selections differ from those made in the manufacturer’s own sample listings, so the results are not identical. d. And then, how is the speed ratio of the reducer determined? There are several unspecified values at present: the reduction gear ratio, the selection of the large and small sprockets. Additionally, there is a difference between the manufacturer’s JMS series of chain conveyors and the MSJ series of chain conveyors described in the \"Design Manual for Transport Machinery\" in many aspects; this includes the details regarding the shaft extension journal, which is not specified in the manual, as well as differences in the diameter of the pitch circle of the internal drive sprockets. This confuses me: should the drawings be made according to the manufacturer’s detailed dimensions, or should they be designed in accordance with general design standards? The key issue is that the manual does not specify the journal dimensions of the main input shaft for certain types of drag chain conveyors; as a result, it is impossible to select an appropriate large sprocket, which is why this question arises. E, regarding the sprocket issue, it’s also a key problem: personally, I think for the sprocket component, depending on its fitting style and purpose, the diameter of the internal hole varies, but there must be some limit, right? How is this aperture limit calculated and determined? I checked Volume 3 of the mechanical manual, which provides a general overview of the hole-size restrictions for small sprockets; there is no detailed information on large sprockets. In summary, when creating drawings, the engineering design unit is essentially going through a selection process; however, this selection process also results in assembly drawings as well as relevant drawings showing the embedded foundation conditions, so as to determine the specifications of the equipment, its layout in the overall plan, and the associated foundation requirements ； For manufacturers of buried scraper units, this task is simpler: all the dimensions related to various types of buried scrapers are fixed values; what’s needed are simply the pre-formed equipment parts and drawings. The length varies depending on the requirements of the installation site, and the location of the material inlet also differs. As long as the transmission mechanism chosen is appropriate and sufficient, that’s fine ； At present, I can only rely on the manual as the sole guideline, while the actual selection is made by commissioning a specific manufacturer. The general nature of the data in the manual, as opposed to the more detailed information provided by the manufacturers, leaves me confused: how should I proceed with a proper design? Strive to meet the requirements of standardized design and selection, and ensure that the equipment’s dimensional parameters are consistent with those specified by the manufacturer! It’s quite difficult! I can only wait for the technicians from the scraper manufacturer to provide me with more detailed information regarding the internal structure of the main drive system as well as its dimensions (but often these details are contradictory; it’s impossible for the manufacturer to provide extremely detailed part drawings and assembly diagrams!) It’s also about protecting independent intellectual property rights! I’m a complete beginner, and my language skills aren’t very good. I hope everyone can take the time to read this while drinking tea and give me some advice; I still have a lot to learn! Thank you all!