Tube Velocity
To prevent tube erosion, use the following recommended maximum velocities for clean water:
ft/s m/s Material
10 3.048 Carbon Steel, 90/10 Cu/Ni
15 4.572 Stainless Steel, 70/30 Cu/Ni
6 1.829 Aluminum, Copper
25 7.620 Titanium
For other liquids, multiply the value above by the following factor:
[ Water Density / Liquid Density ]
http://www.wlv.com/products/databook/ch1_6.pdf