**Rig pump output**, normally in volume per stroke, of mud pumps on the rig is one of important figures that we really need to know because we will use pump out put figures to calculate many parameters such as bottom up strokes, wash out depth, tracking drilling fluid, etc. In this post, you will learn how to calculate pump out put for triplex pump and duplex pump in both Oilfield and Metric Unit.

**Triplex Pump Output Formula**

**Oilfield Unit**

Triplex Pump Output = 0.000243 × (Liner Diameter )^{2}× (Stroke Length)Where,

Triplex pump output in bbl/stk

Liner Diameter in inch

Stroke Length in inch

**Example:**

Determine the pump output in bbl/stk at 100% and 97% efficiency

Liner size = 6 inch

Stroke length = 12 inch

**Triplex pump output @ 100% efficiency**

Triplex pump output @ 100% = 0.000243 × 6^{2} × 12

Triplex pump output @ 100% = 0.104976 bbl/stk

**Triplex pump output @ 97% efficiency
**Adjust the triplex pump output for 97% efficiency:

Triplex pump output @ 97% = 0.104976 × 0.97 bbl/stk

Triplex pump output @ 97% = 0.101827 bbl/stk

**Metric Unit**

Triplex Pump Output = 2.3576 × 10^{-9}× (Liner Diameter )^{2}× (Stroke Length)Where,

Triplex pump output in m

^{3}/stkLiner Diameter in mm

Stroke Length in mm

**Example:**

Determine the pump output in bbl/stk at 100% and 97% efficiency

Liner size = 152.4 mm

Stroke length = 304.8 mm

**Triplex pump output @ 100 % efficiency
**

Triplex pump output @ 100% = 2.3576 × 10

^{-9}× 152.4

^{2}× 304.8

Triplex pump output @ 100% = 0.016690 m

^{3}/stk

**Triplex pump output @ 97% efficiency
**Adjust the triplex pump output for 97% efficiency:

Triplex pump output @ 97% = 0.016690 × 0.97 m

^{3}/stk

Triplex pump output @ 97% = 0.016189 m

^{3}/stk

**Duplex Pump Output Formula**

**Oilfield Unit**

Duplex Pump Output = 0.000162 × S × [2(D)^{2}– d^{2}]Where:

Duplex pump output in bbl/stk

D = liner diameter in inch

S = stroke length in inch

d = rod diameter in inch

**Example:**

Determine the duplex pump output in bbl/stk at 100% and 85% efficiency

Liner diameter = 6 inch

Stroke length = 12 inch

Rod diameter = 2.0 in.

**Duplex pump output @ 100 % efficiency**

Duplex pump output @ 100% = 0.000162 × 12 × [2 (6) ^{2} -2^{2} ]

Duplex pump output @ 100% = 0.13219 bbl/stk

**Duplex pump output @ 85% efficiency**

Adjust pump output for 85% efficiency:

Duplex pump output @ 85% = 0.132192 × 0.85 bbl/stk

Duplex pump output @ 85% = 0.11236 bbl/stk

**Metric Unit**

Duplex Pump Output =1.57172 × 10^{-9}× S × [2(D)^{2}– d^{2}]Where:

Duplex pump output in m

^{3}/stk

D = liner diameter in mm

S = stroke length in mm

d = rod diameter in mm

Example: Determine the duplex pump output in m3/stk at 100% and 85% efficiency

Liner diameter = 152.4 mm

Stroke length = 304.8 mm

Rod diameter = 50.8 mm

**Duplex pump output @ 100 % efficiency**

Duplex pump output@ 100% = 1.57172 × 10^{-9} × 304.8 × [2 (152.4) ^{2} -50.8^{2} ]

Duplex pump output@ 100% = 0.02102 m^{3}/stk

**Duplex pump output @ 85% efficiency**

Duplex pump output@ 85% = 0.02102 × 0.85 m^{3}/stk

Duplex pump output @ 85% = 0.01786 bbl/stk

**Please find the Excel sheet to calculate triplex pump output and duplex pump output**

**Ref books: **

Lapeyrouse, N.J., 2002. Formulas and calculations for drilling, production and workover, Boston: Gulf Professional publishing.

Bourgoyne, A.J.T., Chenevert , M.E. & Millheim, K.K., 1986. SPE Textbook Series, Volume 2: Applied Drilling Engineering, Society of Petroleum Engineers.

Mitchell, R.F., Miska, S. & Aadny, B.S., 2011. Fundamentals of drilling engineering, Richardson, TX: Society of Petroleum Engineers.