Rod Pump Design Calculator
Calculate polished rod loads, prime mover horsepower, pump efficiency, counterbalance, and rod stress for sucker rod pumping systems.
Input Parameters
PD = 0.1166 × Ap × S × N | PPRL = Wf + Wr + Facc | HP = (PPRL × S × N) / 33000 × 1.5
Plunger Displacement
--
bbl/d
Pump Efficiency
--
%
Prime Mover HP
--
hp (1.5x safety)
Rod Stress
--
psi
Load Analysis
Fluid Load (Wf)
--
lbs
Rod String Weight (Wr)
--
lbs
Acceleration Force
--
lbs
PPRL (Peak Load)
--
lbs
MPRL (Min Load)
--
lbs
Counterbalance
--
lbs
How this was calculated
Plunger Displacement: PD = 0.1166 x Ap x S x N, where Ap = plunger area (in2), S = stroke length (in), N = pumping speed (SPM).
Fluid Load: Wf = 0.052 x SG x 62.4 x Ap x D. This is the weight of the fluid column acting on the plunger area over the pump depth.
Rod String Weight: Wr = rod weight per foot x pump depth.
Acceleration (Mills): Facc = (Wr x S x N^2) / 70500. This accounts for inertia forces on the rod string.
PPRL: Peak Polished Rod Load = Wf + Wr + Facc (upstroke).
MPRL: Minimum Polished Rod Load = Wr - Facc (downstroke).
Prime Mover HP: HP = (PPRL x S x N) / 33000 x 1.5 safety factor.
Counterbalance: CB = (PPRL + MPRL) / 2.
Rod Stress: PPRL / rod cross-sectional area.
Reference: Guo & Ghalambor, Petroleum Production Engineering.
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Book a free strategy call →Understanding Sucker Rod Pump Design
Sucker rod pumping is the most widely used artificial lift method worldwide, accounting for approximately 80% of artificially lifted wells. Proper design of the rod pump system is essential to maximize production, minimize failures, and optimize operating costs. The key design parameters include plunger displacement, polished rod loads, prime mover sizing, and rod stress analysis.
The plunger displacement (PD) represents the theoretical maximum volume the pump can displace per day. Actual production is always less due to pump slippage, gas interference, and incomplete fillage. The ratio of actual production to PD gives the pump efficiency, typically ranging from 50% to 90% in well-designed systems.
The polished rod load determines the structural requirements of the pumping unit. The peak polished rod load (PPRL) occurs during the upstroke when the rod string carries both the fluid column weight and its own weight, plus dynamic acceleration forces. Mills' acceleration factor provides a simple but effective estimate of these inertial loads.
All calculations run entirely in your browser. Built by Groundwork Analytics, an AI and engineering company serving the energy industry. Get in touch or email info@petropt.com.