Keep water at 1–2.5 m/s

Size pipes so water flows between about 1 and 2.5 m/s.

Why it works

Slower and sediment settles; faster and you get erosion, noise and water hammer. Pump suction lines sit at the low end.

Do it exactly

Estimate with the rule, then check it against the calculator that models it properly.

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More in Mechanical

• The bolt-torque shortcutTightening torque ≈ 0.2 × preload × bolt diameter (dry steel).
• Torque mostly fights frictionRoughly 90% of tightening torque is lost to friction; only ~10% actually stretches the bolt.
• Deflection limits: span/250Keep beam deflection under span/250 generally, span/360 where people will notice a bouncy floor.
• Depth beats width, cubedDouble a beam’s depth and its deflection drops 8-fold. Double its width and it only halves.

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