guddu SIngh

A lot depends on your compressor size, working pressure, total air demand, and how far the lines need to run, but one thing I would avoid is using general water/plumbing pipe unless it is clearly rated for compressed air service. For a workshop setup, the pipe choice should be based on safety, pressure drop, moisture, corrosion, and future maintenance. Black iron/steel has been used for years and can work well, but it may rust internally over time if moisture is not managed properly. Copper is clean and reliable but can become expensive. Aluminium modular compressed air piping is becoming popular because it is lightweight, corrosion-resistant, easy to install, and easier to expand later. The layout matters just as much as the pipe material. A proper ring main with correctly sized pipe, drain points, drop legs, isolation valves, filters, and moisture separators will usually perform much better than a simple dead-end line. Poor layout can cause pressure loss, water carryover, leaks, and reduced tool performance even if the pipe material itself is good. Main points I would consider: Use pipe specifically rated for compressed air. Size the pipe based on CFM demand and distance, not just compressor outlet size. Avoid sharp unnecessary bends where possible. Install drop legs from the top of the main line, not directly from the bottom. Add drain points at low areas. Plan for future machines or extra air points. Do not ignore moisture control. In short, I would treat this as a full system design question, not just a “which pipe is cheapest” question. A slightly better piping system can save a lot later through fewer leaks, cleaner air, lower pressure drop, and less maintenance.