Brief description

The hydraulic ram pump is a cyclic water pump that uses the energy of a large volume of water falling through a small head to lift a small portion of that water to a much higher head. It is a self-powered device that requires no external energy source other than the kinetic energy of flowing water.

Use / Function

• Water Supply: Lifting water from a stream or spring to a storage tank at a higher elevation.
• Irrigation: Providing water for crops in uphill fields.
• Livestock: Supplying water to troughs in remote pastures.
• Scale: Small to medium scale (domestic and agricultural).

Operating principle

The pump operates using the water hammer effect:

1. Acceleration: Water flows from the source through a “drive pipe” and out through an open “waste valve.”
2. Closure: As the flow reaches a certain speed, the waste valve slams shut due to dynamic pressure.
3. Pressure Spike: The sudden stop of water creates a high-pressure spike (water hammer).
4. Delivery: This pressure forces a portion of the water through a “check valve” into an “air chamber” and up the “delivery pipe.”
5. Cycle Restart: The pressure in the drive pipe drops, the check valve closes, and the waste valve reopens by gravity or a spring, starting the cycle again.

How to create it

• Minimum functional version: An assembly of standard pipe fittings (T-junctions, check valves, and a weighted waste valve).
• Essential: A drive pipe of sufficient length and a fall (head) of at least 1-2 meters.
• Technical level: Intermediate (requires understanding of plumbing and pressure).

Materials needed

• Essential materials:
  • Iron or Steel: For pipes and heavy-duty fittings.
  • Copper or Brass: For valves and internal components.
  • Rubber/Leather: For valve gaskets and seals.
• Tools:
  • Wrench: For tightening pipe connections.
  • File: To smooth edges.
  • Drill: To modify valve components.
• Possible substitutes:
  • Plastic (PVC): For modern low-pressure versions.
  • Hollow Logs: Historically used for drive pipes in very primitive versions, though pressure limits are very low.

Variants and improvements

• Simple Ram: Basic assembly of valves.
• Compound Ram: Can use a “dirty” water source to pump clean water from a separate source.
• Air Chamber Improvements: Using a bladder to prevent air from being absorbed by the water over time.

Limits and risks

• Efficiency: Only a small percentage (typically 10-20%) of the total water flow is actually pumped uphill; the rest is “wasted.”
• Noise: The constant “clacking” of the valves can be loud.
• Mechanical Wear: The valves move thousands of times a day and eventually require maintenance or replacement.
• Freezing: In cold climates, the pump and pipes must be protected from ice.