A hydraulic ram uses cyclic water hammer from a drive flow to lift a smaller delivery flow without an external motor. This calculator compares selected geometry with declared 5H–12H drive-pipe and 20H lift reference rules; those rules are not universal design limits.
Hydraulic Ram Selected Rule-Range Reference
Compare selected hydraulic-ram geometry with declared rule ranges while viewing the complete source-to-delivery path.
Equation Used
- Drive head is positive and all lengths use the same unit.
- The 5H–12H pipe band and 20H lift are selected screening references, not universal limits.
- The animation is illustrative and not time-scaled to the selected hydraulic system.
- Delivered flow, efficiency, surge, stress, valve dynamics, fatigue and safe installation are excluded.
A zero pipe deviation means only that the selected length lies inside the declared 5H–12H comparison band.
Connected source, drive pipe, valves and air vessel
The animation shows an elevated source feeding a finite drive pipe, a ram body with waste and delivery check valves, an air vessel and a rising delivery line. Valve and pulse motion are illustrative and are not timed performance predictions.
What the calculator determines
Select drive head H, drive-pipe length L and delivery head Hd. The calculator reports L/H, Hd/H, the selected 20H lift reference and distance outside the selected 5H–12H pipe band.
Selected rule-range arithmetic
Length ratio = L/H; lift ratio = Hd/H; reference lift = 20H; pipe deviation = distance from L to the closed interval [5H,12H].
Selected-input arithmetic
For H = 6 m, L = 50 m and Hd = 48 m, L/H = 8.33 and Hd/H = 8. The selected pipe length lies inside the 30–72 m reference band, so deviation is zero.
Screening reference only
The rule ranges do not predict delivered flow, efficiency, pulse timing, pressure surge, pipe stress, valve sizing, air-vessel behavior, noise, fatigue, water quality or safe installation. Site-specific hydraulic analysis and manufacturer guidance are required.
Questions
Does zero deviation mean the pump will work?
No. It only means the selected pipe length lies within the declared comparison band.
Is 20H a guaranteed lift?
No. It is a displayed screening reference, not a performance guarantee.
Primary technical reference
- USDA NRCS National Engineering Handbook, Chapter 12 — official hydraulic-ram description and cross-section showing source, drive pipe, waste valve, delivery check, air chamber and delivery pipe.
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