Recommended Tubing size to use for various hp pumps in vacuum conveying (5000 fpm conveying velocity)

Vacuum Pump HP	Tubing size (in.)	Conveying Air (cfm)
5	2	120
7.5	2.5	155
10	2.5	225
10	3	200
15	3.5	300
20	4	475
30	5	665

Conveying tubing recommended bend radius

Tubing size (in.)	Mat'l line bend radius (in.)	Vacuum line bend radius (in.)
2	18, 24	9
2.5	30	9
3	36	9, 12
3.5	36, 48	12
4	36, 48	12,18
5	48	18, 24

Equivalent Feet
Horizontal distance = 1 ft
vertical distance = 2 ft
90 degree elbow = 20 ft
flex hose = 4 ft
in-line Y = 3% derate per Y
20% derate for proportioning
Purge valve = 20 to 50% derate, depending on distance
30% derate for powder conveying