Piping issues
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The common connections used in container fabrication are flanges. Due to the limited space available in the equipment, it is considered possible to switch to threaded connections for some pipes; this way, the associated valves can be smaller and take up less space. The pipe diameter is DN25, and the medium is nitrogen/compressed air. I’m not sure if this approach is feasible. If not, then the container flanges should be retained, with British-style pipes used for piping connections and British-style flanges for connecting to the container (so that the bolt holes align). All other piping fittings and valves should use threaded connections. Please discuss which option is more reasonable
According to Section 1.15 Pipe Connections (4) Threaded Connections in the Chemical Process Design Manual (5th Edition – Volume 2), page 201, these connections are generally suitable for welded steel pipes, galvanized welded steel pipes, or rigid polyvinyl chloride plastic pipes with pipe diameters of ≤50 mm (≤150 mm may be used for indoor exposed water supply pipes), where the operating pressure is below 1.0 MPa and the medium temperature is ≤100°C; they are used to connect such pipes to threaded valves and fittings.
According to Page 217 of the \"Chemical Process Design Manual (5th Edition – Volume 2), under the General Principles for Pipeline Design, point ⑧: Since leaks are likely to occur at pipe flanges, pipelines should be connected using flanges at the points where they connect to equipment, valves, and special fittings; elsewhere, butt welding should be used (for DN 40mm pipes, socket welding or clamp fitting may be employed). For pipes with PN ≤0.8MPa and DN ≥50mm, except for valves connected by flanges and equipment interfaces that use flange connections, all other connections are made by butt welding (including welded steel pipes). However, for galvanized welded pipes, welding is not permitted unless there are special requirements, DN
Refer to the examples of pressure pipeline design; the piping design specifications state that threaded connections are permitted when the pipe diameter is 50 mm or less. However, flanges must be used for connections between valves and equipment. In areas at the bottom of spherical tanks where leaks caused by flanges are a concern, direct welding can be used, but threaded connections are not allowed.
The nozzles to which the equipment is connected are generally not joined using threads