27/09/2026
To pump concrete 40 metres vertically and 80 metres of pipeline at 80 m³/hr requires just over 10 bar of pump pressure. Here is the complete calculation — friction loss, static head, and safety margin.
Save this — concrete pumping pressure reference.
TOTAL PUMP PRESSURE: P = P_friction + P_static + P_reserve
Given: Q=80 m³/hr=0.0222 m³/s | D=125mm | L_pipeline=80m | H=40m | Slump=180mm
Flow velocity: v = 0.0222/0.01227 = 1.81 m/s
Friction loss (180mm slump concrete, 125mm pipe, f≈600 Pa/m):
ΔP_friction = 600 × 80 = 48,000 Pa = 0.48 bar
Static head pressure:
ΔP_static = 2,300 × 9.81 × 40 = 902,520 Pa = 9.03 bar
Reserve: 0.5 bar
TOTAL: P_pump = 0.48 + 9.03 + 0.5 = 10.01 bar
Selected pump minimum rating: 15 bar (1.5× working pressure factor)
FACTORS THAT INCREASE PUMPING PRESSURE:
Lower slump (stiffer mix): friction doubles every ~20mm slump reduction
Smaller pipe diameter: pressure ∝ 1/D⁴ — halving diameter = 16× pressure!
More bends/elbows: each 90° bend ≈ 3m extra equivalent pipe length
Higher aggregate size: reduces lubrication layer on pipe wall
LUBRICATION MORTAR:
Before pumping concrete, pump a cement-sand slurry (lubricating mortar) to coat the pipe interior. Failure to do so causes the first concrete to de-water on the dry pipe — causing a plug and potential pipe burst.
Save this — concrete pumping pressure reference.
What is the highest pour you have ever pumped concrete to? What pump pressure was required?
